[PATCH v3 0/4] MBIST work around (WAR) for Tegra210

[PATCH v3 0/4] MBIST work around (WAR) for Tegra210

[Peter De Schrijver]

This patch series introduces the Memory Built-In Self Test (MBIST)
work around (WAR) needed when power ungating certain domains. More
details can be found in 'clk: tegra: MBIST WAR for Tegra210'. I choose to
implement the WAR in the Tegra210 clock driver, because most accesses are
to CAR registers and for the VENC domain, we need to make sure the CSI
clock source is not changed during the WAR execution.

Peter De Schrijver (4):
  clk: tegra: Add la clock for Tegra210
  clk: tegra: add fence_delay for clock registers
  clk: tegra: MBIST work around for Tegra210
  soc/tegra: pmc: apply MBIST work around fo Tegra210

 drivers/clk/tegra/clk-tegra210.c         | 409 ++++++++++++++++++++++++++++++-
 drivers/clk/tegra/clk.h                  |   7 +
 drivers/soc/tegra/pmc.c                  |   5 +
 include/dt-bindings/clock/tegra210-car.h |   2 +-
 include/linux/clk/tegra.h                |   5 +
 5 files changed, 425 insertions(+), 3 deletions(-)

-- 
1.9.1

[PATCH v3 0/4] MBIST work around (WAR) for Tegra210

[Peter De Schrijver]

This patch series introduces the Memory Built-In Self Test (MBIST)
work around (WAR) needed when power ungating certain domains. More
details can be found in 'clk: tegra: MBIST WAR for Tegra210'. I choose to
implement the WAR in the Tegra210 clock driver, because most accesses are
to CAR registers and for the VENC domain, we need to make sure the CSI
clock source is not changed during the WAR execution.

Peter De Schrijver (4):
  clk: tegra: Add la clock for Tegra210
  clk: tegra: add fence_delay for clock registers
  clk: tegra: MBIST work around for Tegra210
  soc/tegra: pmc: apply MBIST work around fo Tegra210

 drivers/clk/tegra/clk-tegra210.c         | 409 ++++++++++++++++++++++++++++++-
 drivers/clk/tegra/clk.h                  |   7 +
 drivers/soc/tegra/pmc.c                  |   5 +
 include/dt-bindings/clock/tegra210-car.h |   2 +-
 include/linux/clk/tegra.h                |   5 +
 5 files changed, 425 insertions(+), 3 deletions(-)

-- 
1.9.1

[PATCH v3 1/4] clk: tegra: Add la clock for Tegra210

[Peter De Schrijver]

This clock is needed by the memory built-in self test work around.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk-tegra210.c         | 14 ++++++++++++++
 include/dt-bindings/clock/tegra210-car.h |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
index 9e62608..f790c2d 100644
--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -41,6 +41,7 @@
 #define CLK_SOURCE_CSITE 0x1d4
 #define CLK_SOURCE_EMC 0x19c
 #define CLK_SOURCE_SOR1 0x410
+#define CLK_SOURCE_LA 0x1f8
 
 #define PLLC_BASE 0x80
 #define PLLC_OUT 0x84
@@ -2654,6 +2655,13 @@ static int tegra210_init_pllu(void)
 			      sor1_parents_idx, 0, &sor1_lock),
 };
 
+static const char * const la_parents[] = {
+	"pll_p", "pll_c2", "pll_c", "pll_c3", "pll_re_out1", "pll_a1", "clk_m", "pll_c4_out0"
+};
+
+static struct tegra_clk_periph tegra210_la =
+	TEGRA_CLK_PERIPH(29, 7, 9, 0, 8, 1, TEGRA_DIVIDER_ROUND_UP, 76, 0, NULL, 0);
+
 static __init void tegra210_periph_clk_init(void __iomem *clk_base,
 					    void __iomem *pmc_base)
 {
@@ -2700,6 +2708,12 @@ static __init void tegra210_periph_clk_init(void __iomem *clk_base,
 					     periph_clk_enb_refcnt);
 	clks[TEGRA210_CLK_DSIB] = clk;
 
+	/* la */
+	clk = tegra_clk_register_periph("la", la_parents,
+			ARRAY_SIZE(la_parents), &tegra210_la, clk_base,
+			CLK_SOURCE_LA, 0);
+	clks[TEGRA210_CLK_LA] = clk;
+
 	/* emc mux */
 	clk = clk_register_mux(NULL, "emc_mux", mux_pllmcp_clkm,
 			       ARRAY_SIZE(mux_pllmcp_clkm), 0,
diff --git a/include/dt-bindings/clock/tegra210-car.h b/include/dt-bindings/clock/tegra210-car.h
index 6422314..6b77e72 100644
--- a/include/dt-bindings/clock/tegra210-car.h
+++ b/include/dt-bindings/clock/tegra210-car.h
@@ -95,7 +95,7 @@
 #define TEGRA210_CLK_CSITE 73
 /* 74 */
 /* 75 */
-/* 76 */
+#define TEGRA210_CLK_LA 76
 /* 77 */
 #define TEGRA210_CLK_SOC_THERM 78
 #define TEGRA210_CLK_DTV 79
-- 
1.9.1

[PATCH v3 1/4] clk: tegra: Add la clock for Tegra210

[Peter De Schrijver]

This clock is needed by the memory built-in self test work around.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk-tegra210.c         | 14 ++++++++++++++
 include/dt-bindings/clock/tegra210-car.h |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
index 9e62608..f790c2d 100644
--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -41,6 +41,7 @@
 #define CLK_SOURCE_CSITE 0x1d4
 #define CLK_SOURCE_EMC 0x19c
 #define CLK_SOURCE_SOR1 0x410
+#define CLK_SOURCE_LA 0x1f8
 
 #define PLLC_BASE 0x80
 #define PLLC_OUT 0x84
@@ -2654,6 +2655,13 @@ static int tegra210_init_pllu(void)
 			      sor1_parents_idx, 0, &sor1_lock),
 };
 
+static const char * const la_parents[] = {
+	"pll_p", "pll_c2", "pll_c", "pll_c3", "pll_re_out1", "pll_a1", "clk_m", "pll_c4_out0"
+};
+
+static struct tegra_clk_periph tegra210_la =
+	TEGRA_CLK_PERIPH(29, 7, 9, 0, 8, 1, TEGRA_DIVIDER_ROUND_UP, 76, 0, NULL, 0);
+
 static __init void tegra210_periph_clk_init(void __iomem *clk_base,
 					    void __iomem *pmc_base)
 {
@@ -2700,6 +2708,12 @@ static __init void tegra210_periph_clk_init(void __iomem *clk_base,
 					     periph_clk_enb_refcnt);
 	clks[TEGRA210_CLK_DSIB] = clk;
 
+	/* la */
+	clk = tegra_clk_register_periph("la", la_parents,
+			ARRAY_SIZE(la_parents), &tegra210_la, clk_base,
+			CLK_SOURCE_LA, 0);
+	clks[TEGRA210_CLK_LA] = clk;
+
 	/* emc mux */
 	clk = clk_register_mux(NULL, "emc_mux", mux_pllmcp_clkm,
 			       ARRAY_SIZE(mux_pllmcp_clkm), 0,
diff --git a/include/dt-bindings/clock/tegra210-car.h b/include/dt-bindings/clock/tegra210-car.h
index 6422314..6b77e72 100644
--- a/include/dt-bindings/clock/tegra210-car.h
+++ b/include/dt-bindings/clock/tegra210-car.h
@@ -95,7 +95,7 @@
 #define TEGRA210_CLK_CSITE 73
 /* 74 */
 /* 75 */
-/* 76 */
+#define TEGRA210_CLK_LA 76
 /* 77 */
 #define TEGRA210_CLK_SOC_THERM 78
 #define TEGRA210_CLK_DTV 79
-- 
1.9.1

Re: [PATCH v3 1/4] clk: tegra: Add la clock for Tegra210

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> This clock is needed by the memory built-in self test work around.
> 
> Signed-off-by: Peter De Schrijver <pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> ---
>  drivers/clk/tegra/clk-tegra210.c         | 14 ++++++++++++++
>  include/dt-bindings/clock/tegra210-car.h |  2 +-
>  2 files changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> index 9e62608..f790c2d 100644
> --- a/drivers/clk/tegra/clk-tegra210.c
> +++ b/drivers/clk/tegra/clk-tegra210.c
> @@ -41,6 +41,7 @@
>  #define CLK_SOURCE_CSITE 0x1d4
>  #define CLK_SOURCE_EMC 0x19c
>  #define CLK_SOURCE_SOR1 0x410
> +#define CLK_SOURCE_LA 0x1f8
>  
>  #define PLLC_BASE 0x80
>  #define PLLC_OUT 0x84
> @@ -2654,6 +2655,13 @@ static int tegra210_init_pllu(void)
>  			      sor1_parents_idx, 0, &sor1_lock),
>  };
>  
> +static const char * const la_parents[] = {
> +	"pll_p", "pll_c2", "pll_c", "pll_c3", "pll_re_out1", "pll_a1", "clk_m", "pll_c4_out0"
> +};
> +

I was comparing this with downstream and it appears that the parents are
listed as "pll_p", "pll_c", "pll_m", "clk_m". Can you double check the
above is correct?

Otherwise ...

> +static struct tegra_clk_periph tegra210_la =
> +	TEGRA_CLK_PERIPH(29, 7, 9, 0, 8, 1, TEGRA_DIVIDER_ROUND_UP, 76, 0, NULL, 0);
> +
>  static __init void tegra210_periph_clk_init(void __iomem *clk_base,
>  					    void __iomem *pmc_base)
>  {
> @@ -2700,6 +2708,12 @@ static __init void tegra210_periph_clk_init(void __iomem *clk_base,
>  					     periph_clk_enb_refcnt);
>  	clks[TEGRA210_CLK_DSIB] = clk;
>  
> +	/* la */
> +	clk = tegra_clk_register_periph("la", la_parents,
> +			ARRAY_SIZE(la_parents), &tegra210_la, clk_base,
> +			CLK_SOURCE_LA, 0);
> +	clks[TEGRA210_CLK_LA] = clk;
> +
>  	/* emc mux */
>  	clk = clk_register_mux(NULL, "emc_mux", mux_pllmcp_clkm,
>  			       ARRAY_SIZE(mux_pllmcp_clkm), 0,
> diff --git a/include/dt-bindings/clock/tegra210-car.h b/include/dt-bindings/clock/tegra210-car.h
> index 6422314..6b77e72 100644
> --- a/include/dt-bindings/clock/tegra210-car.h
> +++ b/include/dt-bindings/clock/tegra210-car.h
> @@ -95,7 +95,7 @@
>  #define TEGRA210_CLK_CSITE 73
>  /* 74 */
>  /* 75 */
> -/* 76 */
> +#define TEGRA210_CLK_LA 76
>  /* 77 */
>  #define TEGRA210_CLK_SOC_THERM 78
>  #define TEGRA210_CLK_DTV 79

Acked-by: Jon Hunter <jonathanh-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 1/4] clk: tegra: Add la clock for Tegra210

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> This clock is needed by the memory built-in self test work around.
> 
> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/clk/tegra/clk-tegra210.c         | 14 ++++++++++++++
>  include/dt-bindings/clock/tegra210-car.h |  2 +-
>  2 files changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> index 9e62608..f790c2d 100644
> --- a/drivers/clk/tegra/clk-tegra210.c
> +++ b/drivers/clk/tegra/clk-tegra210.c
> @@ -41,6 +41,7 @@
>  #define CLK_SOURCE_CSITE 0x1d4
>  #define CLK_SOURCE_EMC 0x19c
>  #define CLK_SOURCE_SOR1 0x410
> +#define CLK_SOURCE_LA 0x1f8
>  
>  #define PLLC_BASE 0x80
>  #define PLLC_OUT 0x84
> @@ -2654,6 +2655,13 @@ static int tegra210_init_pllu(void)
>  			      sor1_parents_idx, 0, &sor1_lock),
>  };
>  
> +static const char * const la_parents[] = {
> +	"pll_p", "pll_c2", "pll_c", "pll_c3", "pll_re_out1", "pll_a1", "clk_m", "pll_c4_out0"
> +};
> +

I was comparing this with downstream and it appears that the parents are
listed as "pll_p", "pll_c", "pll_m", "clk_m". Can you double check the
above is correct?

Otherwise ...

> +static struct tegra_clk_periph tegra210_la =
> +	TEGRA_CLK_PERIPH(29, 7, 9, 0, 8, 1, TEGRA_DIVIDER_ROUND_UP, 76, 0, NULL, 0);
> +
>  static __init void tegra210_periph_clk_init(void __iomem *clk_base,
>  					    void __iomem *pmc_base)
>  {
> @@ -2700,6 +2708,12 @@ static __init void tegra210_periph_clk_init(void __iomem *clk_base,
>  					     periph_clk_enb_refcnt);
>  	clks[TEGRA210_CLK_DSIB] = clk;
>  
> +	/* la */
> +	clk = tegra_clk_register_periph("la", la_parents,
> +			ARRAY_SIZE(la_parents), &tegra210_la, clk_base,
> +			CLK_SOURCE_LA, 0);
> +	clks[TEGRA210_CLK_LA] = clk;
> +
>  	/* emc mux */
>  	clk = clk_register_mux(NULL, "emc_mux", mux_pllmcp_clkm,
>  			       ARRAY_SIZE(mux_pllmcp_clkm), 0,
> diff --git a/include/dt-bindings/clock/tegra210-car.h b/include/dt-bindings/clock/tegra210-car.h
> index 6422314..6b77e72 100644
> --- a/include/dt-bindings/clock/tegra210-car.h
> +++ b/include/dt-bindings/clock/tegra210-car.h
> @@ -95,7 +95,7 @@
>  #define TEGRA210_CLK_CSITE 73
>  /* 74 */
>  /* 75 */
> -/* 76 */
> +#define TEGRA210_CLK_LA 76
>  /* 77 */
>  #define TEGRA210_CLK_SOC_THERM 78
>  #define TEGRA210_CLK_DTV 79

Acked-by: Jon Hunter <jonathanh@nvidia.com>

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 1/4] clk: tegra: Add la clock for Tegra210

[Peter De Schrijver]

On Wed, Jan 24, 2018 at 10:03:31AM +0000, Jon Hunter wrote:
> 
> On 23/01/18 09:22, Peter De Schrijver wrote:
> > This clock is needed by the memory built-in self test work around.
> > 
> > Signed-off-by: Peter De Schrijver <pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> > ---
> >  drivers/clk/tegra/clk-tegra210.c         | 14 ++++++++++++++
> >  include/dt-bindings/clock/tegra210-car.h |  2 +-
> >  2 files changed, 15 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> > index 9e62608..f790c2d 100644
> > --- a/drivers/clk/tegra/clk-tegra210.c
> > +++ b/drivers/clk/tegra/clk-tegra210.c
> > @@ -41,6 +41,7 @@
> >  #define CLK_SOURCE_CSITE 0x1d4
> >  #define CLK_SOURCE_EMC 0x19c
> >  #define CLK_SOURCE_SOR1 0x410
> > +#define CLK_SOURCE_LA 0x1f8
> >  
> >  #define PLLC_BASE 0x80
> >  #define PLLC_OUT 0x84
> > @@ -2654,6 +2655,13 @@ static int tegra210_init_pllu(void)
> >  			      sor1_parents_idx, 0, &sor1_lock),
> >  };
> >  
> > +static const char * const la_parents[] = {
> > +	"pll_p", "pll_c2", "pll_c", "pll_c3", "pll_re_out1", "pll_a1", "clk_m", "pll_c4_out0"
> > +};
> > +
> 
> I was comparing this with downstream and it appears that the parents are
> listed as "pll_p", "pll_c", "pll_m", "clk_m". Can you double check the
> above is correct?
> 

For all I can see the parents as listed in dowstream are incorrect. Likely
only pll_p is used in practice, so noone has noticed this. pll_m for example
can only be used by emc since T210, so it cannot be part of the parent list
of la.

Peter.

Re: [PATCH v3 1/4] clk: tegra: Add la clock for Tegra210

[Peter De Schrijver]

On Wed, Jan 24, 2018 at 10:03:31AM +0000, Jon Hunter wrote:
> 
> On 23/01/18 09:22, Peter De Schrijver wrote:
> > This clock is needed by the memory built-in self test work around.
> > 
> > Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> > ---
> >  drivers/clk/tegra/clk-tegra210.c         | 14 ++++++++++++++
> >  include/dt-bindings/clock/tegra210-car.h |  2 +-
> >  2 files changed, 15 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> > index 9e62608..f790c2d 100644
> > --- a/drivers/clk/tegra/clk-tegra210.c
> > +++ b/drivers/clk/tegra/clk-tegra210.c
> > @@ -41,6 +41,7 @@
> >  #define CLK_SOURCE_CSITE 0x1d4
> >  #define CLK_SOURCE_EMC 0x19c
> >  #define CLK_SOURCE_SOR1 0x410
> > +#define CLK_SOURCE_LA 0x1f8
> >  
> >  #define PLLC_BASE 0x80
> >  #define PLLC_OUT 0x84
> > @@ -2654,6 +2655,13 @@ static int tegra210_init_pllu(void)
> >  			      sor1_parents_idx, 0, &sor1_lock),
> >  };
> >  
> > +static const char * const la_parents[] = {
> > +	"pll_p", "pll_c2", "pll_c", "pll_c3", "pll_re_out1", "pll_a1", "clk_m", "pll_c4_out0"
> > +};
> > +
> 
> I was comparing this with downstream and it appears that the parents are
> listed as "pll_p", "pll_c", "pll_m", "clk_m". Can you double check the
> above is correct?
> 

For all I can see the parents as listed in dowstream are incorrect. Likely
only pll_p is used in practice, so noone has noticed this. pll_m for example
can only be used by emc since T210, so it cannot be part of the parent list
of la.

Peter.

[PATCH v3 2/4] clk: tegra: add fence_delay for clock registers

[Peter De Schrijver]

To ensure writes to clock registers have properly propagated through the
clock control logic and state machines, we need to ensure the writes have
been posted in the registers and wait for 1us after that.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 3b2763d..ba7e20e 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -812,4 +812,11 @@ static inline struct clk *tegra_clk_register_emc(void __iomem *base,
 u16 tegra_pll_get_fixed_mdiv(struct clk_hw *hw, unsigned long input_rate);
 int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
 
+/* Combined read fence with delay */
+#define fence_udelay(delay, reg)	\
+	do {				\
+		readl(reg);		\
+		udelay(delay);		\
+	} while (0)
+
 #endif /* TEGRA_CLK_H */
-- 
1.9.1

[PATCH v3 2/4] clk: tegra: add fence_delay for clock registers

[Peter De Schrijver]

To ensure writes to clock registers have properly propagated through the
clock control logic and state machines, we need to ensure the writes have
been posted in the registers and wait for 1us after that.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
index 3b2763d..ba7e20e 100644
--- a/drivers/clk/tegra/clk.h
+++ b/drivers/clk/tegra/clk.h
@@ -812,4 +812,11 @@ static inline struct clk *tegra_clk_register_emc(void __iomem *base,
 u16 tegra_pll_get_fixed_mdiv(struct clk_hw *hw, unsigned long input_rate);
 int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
 
+/* Combined read fence with delay */
+#define fence_udelay(delay, reg)	\
+	do {				\
+		readl(reg);		\
+		udelay(delay);		\
+	} while (0)
+
 #endif /* TEGRA_CLK_H */
-- 
1.9.1

Re: [PATCH v3 2/4] clk: tegra: add fence_delay for clock registers

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> To ensure writes to clock registers have properly propagated through the
> clock control logic and state machines, we need to ensure the writes have
> been posted in the registers and wait for 1us after that.
> 
> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/clk/tegra/clk.h | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
> index 3b2763d..ba7e20e 100644
> --- a/drivers/clk/tegra/clk.h
> +++ b/drivers/clk/tegra/clk.h
> @@ -812,4 +812,11 @@ static inline struct clk *tegra_clk_register_emc(void __iomem *base,
>  u16 tegra_pll_get_fixed_mdiv(struct clk_hw *hw, unsigned long input_rate);
>  int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
>  
> +/* Combined read fence with delay */
> +#define fence_udelay(delay, reg)	\
> +	do {				\
> +		readl(reg);		\
> +		udelay(delay);		\
> +	} while (0)
> +
>  #endif /* TEGRA_CLK_H */

Not sure we need to pass the delay here if it is always 1us per the
description. But it is fine with me so ...

Acked-by: Jon Hunter <jonathanh@nvidia.com>

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 2/4] clk: tegra: add fence_delay for clock registers

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> To ensure writes to clock registers have properly propagated through the
> clock control logic and state machines, we need to ensure the writes have
> been posted in the registers and wait for 1us after that.
> 
> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/clk/tegra/clk.h | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
> index 3b2763d..ba7e20e 100644
> --- a/drivers/clk/tegra/clk.h
> +++ b/drivers/clk/tegra/clk.h
> @@ -812,4 +812,11 @@ static inline struct clk *tegra_clk_register_emc(void __iomem *base,
>  u16 tegra_pll_get_fixed_mdiv(struct clk_hw *hw, unsigned long input_rate);
>  int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div);
>  
> +/* Combined read fence with delay */
> +#define fence_udelay(delay, reg)	\
> +	do {				\
> +		readl(reg);		\
> +		udelay(delay);		\
> +	} while (0)
> +
>  #endif /* TEGRA_CLK_H */

Not sure we need to pass the delay here if it is always 1us per the
description. But it is fine with me so ...

Acked-by: Jon Hunter <jonathanh@nvidia.com>

Cheers
Jon

-- 
nvpublic

[PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Peter De Schrijver]

Tegra210 has a hw bug which can cause IP blocks to lock up when ungating a
domain. The reason is that the logic responsible for resetting the memory
built-in self test mode can come up in an undefined state because its
clock is gated by a second level clock gate (SLCG). Work around this by
making sure the logic will get some clock edges by ensuring the relevant
clock is enabled and temporarily override the relevant SLCGs.
Unfortunately for some IP blocks, the control bits for overriding the
SLCGs are not in CAR, but in the IP block itself. This means we need to
map a few extra register banks in the clock code.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk-tegra210.c | 395 ++++++++++++++++++++++++++++++++++++++-
 include/linux/clk/tegra.h        |   5 +
 2 files changed, 398 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
index f790c2d..f61ec1f 100644
--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -22,10 +22,12 @@
 #include <linux/of_address.h>
 #include <linux/delay.h>
 #include <linux/export.h>
+#include <linux/mutex.h>
 #include <linux/clk/tegra.h>
 #include <dt-bindings/clock/tegra210-car.h>
 #include <dt-bindings/reset/tegra210-car.h>
 #include <linux/iopoll.h>
+#include <soc/tegra/pmc.h>
 
 #include "clk.h"
 #include "clk-id.h"
@@ -232,6 +234,30 @@
 #define CLK_RST_CONTROLLER_RST_DEV_Y_SET 0x2a8
 #define CLK_RST_CONTROLLER_RST_DEV_Y_CLR 0x2ac
 
+#define LVL2_CLK_GATE_OVRA 0xf8
+#define LVL2_CLK_GATE_OVRC 0x3a0
+#define LVL2_CLK_GATE_OVRD 0x3a4
+#define LVL2_CLK_GATE_OVRE 0x554
+
+/* I2S registers to handle during APE MBIST WAR */
+#define TEGRA210_I2S_BASE  0x11000
+#define TEGRA210_I2S_SIZE  0x100
+#define TEGRA210_I2S_CTRLS 5
+#define TEGRA210_I2S_CG    0x88
+#define TEGRA210_I2S_CTRL  0xa0
+
+/* DISPA registers to handle during MBIST WAR */
+#define DC_CMD_DISPLAY_COMMAND 0xc8
+#define DC_COM_DSC_TOP_CTL 0xcf8
+
+/* VIC register to handle during MBIST WAR */
+#define NV_PVIC_THI_SLCG_OVERRIDE_LOW 0x8c
+
+/* APE, DISPA and VIC base addesses needed for MBIST WAR */
+#define TEGRA210_APE_BASE  0x702c0000
+#define TEGRA210_DISPA_BASE 0x54200000
+#define TEGRA210_VIC_BASE  0x54340000
+
 /*
  * SDM fractional divisor is 16-bit 2's complement signed number within
  * (-2^12 ... 2^12-1) range. Represented in PLL data structure as unsigned
@@ -256,8 +282,22 @@
 } tegra210_cpu_clk_sctx;
 #endif
 
+struct tegra210_domain_mbist_war {
+	int (*handle_lvl2_ovr)(struct tegra210_domain_mbist_war *mbist);
+	const u32 lvl2_offset;
+	const u32 lvl2_mask;
+	const unsigned int num_clks;
+	const unsigned int *clk_init_data;
+	struct clk_bulk_data *clks;
+};
+
+static struct clk **clks;
+
 static void __iomem *clk_base;
 static void __iomem *pmc_base;
+static void __iomem *ape_base;
+static void __iomem *dispa_base;
+static void __iomem *vic_base;
 
 static unsigned long osc_freq;
 static unsigned long pll_ref_freq;
@@ -268,6 +308,7 @@
 static DEFINE_SPINLOCK(pll_u_lock);
 static DEFINE_SPINLOCK(sor1_lock);
 static DEFINE_SPINLOCK(emc_lock);
+static DEFINE_MUTEX(lvl2_ovr_lock);
 
 /* possible OSC frequencies in Hz */
 static unsigned long tegra210_input_freq[] = {
@@ -311,6 +352,8 @@
 #define PLLA_MISC2_WRITE_MASK		0x06ffffff
 
 /* PLLD */
+#define PLLD_BASE_CSI_CLKSOURCE		(1 << 23)
+
 #define PLLD_MISC0_EN_SDM		(1 << 16)
 #define PLLD_MISC0_LOCK_OVERRIDE	(1 << 17)
 #define PLLD_MISC0_LOCK_ENABLE		(1 << 18)
@@ -514,6 +557,176 @@ void tegra210_set_sata_pll_seq_sw(bool state)
 }
 EXPORT_SYMBOL_GPL(tegra210_set_sata_pll_seq_sw);
 
+static int tegra210_generic_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 val;
+	int err;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	val = readl_relaxed(clk_base + mbist->lvl2_offset);
+	writel_relaxed(val | mbist->lvl2_mask, clk_base + mbist->lvl2_offset);
+	fence_udelay(1, clk_base);
+	writel_relaxed(val, clk_base + mbist->lvl2_offset);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_venc_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 csi_src, ovra, ovre;
+	int err;
+	unsigned long flags = 0;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+	spin_lock_irqsave(&pll_d_lock, flags);
+
+	csi_src = readl_relaxed(clk_base + PLLD_BASE);
+	writel_relaxed(csi_src | PLLD_BASE_CSI_CLKSOURCE, clk_base + PLLD_BASE);
+	fence_udelay(1, clk_base);
+
+	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
+	writel_relaxed(ovra | BIT(15), clk_base + LVL2_CLK_GATE_OVRA);
+	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(ovre | BIT(3), clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
+	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(csi_src, clk_base + PLLD_BASE);
+	fence_udelay(1, clk_base);
+
+	spin_unlock_irqrestore(&pll_d_lock, flags);
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_disp_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 ovra, dsc_top_ctrl;
+	int err;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
+	writel_relaxed(ovra | BIT(1), clk_base + LVL2_CLK_GATE_OVRA);
+	fence_udelay(1, clk_base);
+
+	dsc_top_ctrl = readl_relaxed(dispa_base + DC_COM_DSC_TOP_CTL);
+	writel_relaxed(dsc_top_ctrl | BIT(2), dispa_base + DC_COM_DSC_TOP_CTL);
+	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
+	writel_relaxed(dsc_top_ctrl, dispa_base + DC_COM_DSC_TOP_CTL);
+	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
+
+	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_vic_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 ovre, val;
+	int err;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(ovre | BIT(5), clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	val = readl_relaxed(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+	writel_relaxed(val | BIT(0) | GENMASK(7, 2) | BIT(24),
+			vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+	fence_udelay(1, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+
+	writel_relaxed(val, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+	readl(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+
+	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_ape_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	int err, i;
+	u32 ovrc, ovre;
+	void __iomem *i2s_base;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	ovrc = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRC);
+	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(ovrc | BIT(1), clk_base + LVL2_CLK_GATE_OVRC);
+	writel_relaxed(ovre | BIT(10) | BIT(11),
+			clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	i2s_base = ape_base + TEGRA210_I2S_BASE;
+	for (i = 0; i < TEGRA210_I2S_CTRLS; i++) {
+		u32 i2s_ctrl;
+
+		i2s_ctrl = readl_relaxed(i2s_base + TEGRA210_I2S_CTRL);
+		writel_relaxed(i2s_ctrl | BIT(10),
+				i2s_base + TEGRA210_I2S_CTRL);
+		writel_relaxed(0, i2s_base + TEGRA210_I2S_CG);
+		readl(i2s_base + TEGRA210_I2S_CG);
+		writel_relaxed(1, i2s_base + TEGRA210_I2S_CG);
+		writel_relaxed(i2s_ctrl, i2s_base + TEGRA210_I2S_CTRL);
+		readl(i2s_base + TEGRA210_I2S_CTRL);
+
+		i2s_base += TEGRA210_I2S_SIZE;
+	}
+
+	writel_relaxed(ovrc, clk_base + LVL2_CLK_GATE_OVRC);
+	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
 static inline void _pll_misc_chk_default(void __iomem *base,
 					struct tegra_clk_pll_params *params,
 					u8 misc_num, u32 default_val, u32 mask)
@@ -2412,13 +2625,137 @@ struct utmi_clk_param {
 	{ "pll_a1", &pll_a1_params, tegra_clk_pll_a1, "pll_ref" },
 };
 
-static struct clk **clks;
-
 static const char * const aclk_parents[] = {
 	"pll_a1", "pll_c", "pll_p", "pll_a_out0", "pll_c2", "pll_c3",
 	"clk_m"
 };
 
+static const unsigned int nvjpg_slcg_clkids[] = { TEGRA210_CLK_NVDEC };
+static const unsigned int nvdec_slcg_clkids[] = { TEGRA210_CLK_NVJPG };
+static const unsigned int sor_slcg_clkids[] = { TEGRA210_CLK_HDA2CODEC_2X,
+	TEGRA210_CLK_HDA2HDMI, TEGRA210_CLK_DISP1, TEGRA210_CLK_DISP2 };
+static const unsigned int disp_slcg_clkids[] = { TEGRA210_CLK_LA,
+	TEGRA210_CLK_HOST1X};
+static const unsigned int xusba_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
+	TEGRA210_CLK_XUSB_DEV };
+static const unsigned int xusbb_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
+	TEGRA210_CLK_XUSB_SS };
+static const unsigned int xusbc_slcg_clkids[] = { TEGRA210_CLK_XUSB_DEV,
+	TEGRA210_CLK_XUSB_SS };
+static const unsigned int venc_slcg_clkids[] = { TEGRA210_CLK_HOST1X,
+	TEGRA210_CLK_PLL_D };
+static const unsigned int ape_slcg_clkids[] = { TEGRA210_CLK_ACLK,
+	TEGRA210_CLK_I2S0, TEGRA210_CLK_I2S1, TEGRA210_CLK_I2S2,
+	TEGRA210_CLK_I2S3, TEGRA210_CLK_I2S4, TEGRA210_CLK_SPDIF_OUT,
+	TEGRA210_CLK_D_AUDIO };
+static const unsigned int vic_slcg_clkids[] = { TEGRA210_CLK_HOST1X };
+
+static struct tegra210_domain_mbist_war tegra210_pg_mbist_war[] = {
+	[TEGRA_POWERGATE_VENC] = {
+		.handle_lvl2_ovr = tegra210_venc_mbist_war,
+		.num_clks = ARRAY_SIZE(venc_slcg_clkids),
+		.clk_init_data = venc_slcg_clkids,
+	},
+	[TEGRA_POWERGATE_SATA] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(0) | BIT(17) | BIT(19),
+	},
+	[TEGRA_POWERGATE_MPE] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRE,
+		.lvl2_mask = BIT(2),
+	},
+	[TEGRA_POWERGATE_SOR] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.num_clks = ARRAY_SIZE(sor_slcg_clkids),
+		.clk_init_data = sor_slcg_clkids,
+		.lvl2_offset = LVL2_CLK_GATE_OVRA,
+		.lvl2_mask = BIT(1) | BIT(2),
+	},
+	[TEGRA_POWERGATE_DIS] = {
+		.handle_lvl2_ovr = tegra210_disp_mbist_war,
+		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
+		.clk_init_data = disp_slcg_clkids,
+	},
+	[TEGRA_POWERGATE_DISB] = {
+		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
+		.clk_init_data = disp_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRA,
+		.lvl2_mask = BIT(2),
+	},
+	[TEGRA_POWERGATE_XUSBA] = {
+		.num_clks = ARRAY_SIZE(xusba_slcg_clkids),
+		.clk_init_data = xusba_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(30) | BIT(31),
+	},
+	[TEGRA_POWERGATE_XUSBB] = {
+		.num_clks = ARRAY_SIZE(xusbb_slcg_clkids),
+		.clk_init_data = xusbb_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(30) | BIT(31),
+	},
+	[TEGRA_POWERGATE_XUSBC] = {
+		.num_clks = ARRAY_SIZE(xusbc_slcg_clkids),
+		.clk_init_data = xusbc_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(30) | BIT(31),
+	},
+	[TEGRA_POWERGATE_VIC] = {
+		.num_clks = ARRAY_SIZE(vic_slcg_clkids),
+		.clk_init_data = vic_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_vic_mbist_war,
+	},
+	[TEGRA_POWERGATE_NVDEC] = {
+		.num_clks = ARRAY_SIZE(nvdec_slcg_clkids),
+		.clk_init_data = nvdec_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(9) | BIT(31),
+	},
+	[TEGRA_POWERGATE_NVJPG] = {
+		.num_clks = ARRAY_SIZE(nvjpg_slcg_clkids),
+		.clk_init_data = nvjpg_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(9) | BIT(31),
+	},
+	[TEGRA_POWERGATE_AUD] = {
+		.num_clks = ARRAY_SIZE(ape_slcg_clkids),
+		.clk_init_data = ape_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_ape_mbist_war,
+	},
+	[TEGRA_POWERGATE_VE2] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRD,
+		.lvl2_mask = BIT(22),
+	},
+};
+
+void tegra210_clk_handle_mbist_war(unsigned int id)
+{
+	int err;
+	struct tegra210_domain_mbist_war *mbist_war;
+
+	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
+		WARN(1, "unknown domain id in MBIST WAR handler\n");
+		return;
+	}
+
+	mbist_war = &tegra210_pg_mbist_war[id];
+	if (!mbist_war->handle_lvl2_ovr)
+		return;
+
+	err = mbist_war->handle_lvl2_ovr(mbist_war);
+	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
+}
+
+
 void tegra210_put_utmipll_in_iddq(void)
 {
 	u32 reg;
@@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
 	return 0;
 }
 
+static void tegra210_mbist_clk_init(void)
+{
+	int i, j;
+
+	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
+		int num_clks = tegra210_pg_mbist_war[i].num_clks;
+		struct clk_bulk_data *clk_data;
+
+		if (!num_clks)
+			continue;
+
+		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
+					 GFP_KERNEL);
+		if (WARN(!clk_data,
+			"no space for MBIST WAR clk array for %d\n", i)) {
+			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
+			continue;
+		}
+
+		tegra210_pg_mbist_war[i].clks = clk_data;
+		for (j = 0; j < num_clks; j++) {
+			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
+			struct clk *clk = clks[clk_id];
+
+			if (IS_ERR(clk)) {
+				clk_data[j].clk = NULL;
+				WARN(1, "clk_id: %d\n", clk_id);
+			} else {
+				clk_data[j].clk = clk;
+			}
+		}
+	}
+}
+
 /**
  * tegra210_clock_init - Tegra210-specific clock initialization
  * @np: struct device_node * of the DT node for the SoC CAR IP block
@@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
 		return;
 	}
 
+	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
+	if (!ape_base) {
+		pr_err("ioremap tegra210 APE failed\n");
+		return;
+	}
+
+	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
+	if (!dispa_base) {
+		pr_err("ioremap tegra210 DISPA failed\n");
+		return;
+	}
+
+	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
+	if (!vic_base) {
+		pr_err("ioremap tegra210 VIC failed\n");
+		return;
+	}
+
 	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
 			      TEGRA210_CAR_BANK_COUNT);
 	if (!clks)
@@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
 	tegra_add_of_provider(np);
 	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
 
+	tegra210_mbist_clk_init();
+
 	tegra_cpu_car_ops = &tegra210_cpu_car_ops;
 }
 CLK_OF_DECLARE(tegra210, "nvidia,tegra210-car", tegra210_clock_init);
diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
index d23c9cf..a3d46f7 100644
--- a/include/linux/clk/tegra.h
+++ b/include/linux/clk/tegra.h
@@ -128,5 +128,10 @@ static inline void tegra_cpu_clock_resume(void)
 extern void tegra210_set_sata_pll_seq_sw(bool state);
 extern void tegra210_put_utmipll_in_iddq(void);
 extern void tegra210_put_utmipll_out_iddq(void);
+#ifndef CONFIG_ARCH_TEGRA_210_SOC
+static inline void tegra210_clk_handle_mbist_war(unsigned int id) {}
+#else
+extern void tegra210_clk_handle_mbist_war(unsigned int id);
+#endif
 
 #endif /* __LINUX_CLK_TEGRA_H_ */
-- 
1.9.1

[PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Peter De Schrijver]

Tegra210 has a hw bug which can cause IP blocks to lock up when ungating a
domain. The reason is that the logic responsible for resetting the memory
built-in self test mode can come up in an undefined state because its
clock is gated by a second level clock gate (SLCG). Work around this by
making sure the logic will get some clock edges by ensuring the relevant
clock is enabled and temporarily override the relevant SLCGs.
Unfortunately for some IP blocks, the control bits for overriding the
SLCGs are not in CAR, but in the IP block itself. This means we need to
map a few extra register banks in the clock code.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/clk/tegra/clk-tegra210.c | 395 ++++++++++++++++++++++++++++++++++++++-
 include/linux/clk/tegra.h        |   5 +
 2 files changed, 398 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
index f790c2d..f61ec1f 100644
--- a/drivers/clk/tegra/clk-tegra210.c
+++ b/drivers/clk/tegra/clk-tegra210.c
@@ -22,10 +22,12 @@
 #include <linux/of_address.h>
 #include <linux/delay.h>
 #include <linux/export.h>
+#include <linux/mutex.h>
 #include <linux/clk/tegra.h>
 #include <dt-bindings/clock/tegra210-car.h>
 #include <dt-bindings/reset/tegra210-car.h>
 #include <linux/iopoll.h>
+#include <soc/tegra/pmc.h>
 
 #include "clk.h"
 #include "clk-id.h"
@@ -232,6 +234,30 @@
 #define CLK_RST_CONTROLLER_RST_DEV_Y_SET 0x2a8
 #define CLK_RST_CONTROLLER_RST_DEV_Y_CLR 0x2ac
 
+#define LVL2_CLK_GATE_OVRA 0xf8
+#define LVL2_CLK_GATE_OVRC 0x3a0
+#define LVL2_CLK_GATE_OVRD 0x3a4
+#define LVL2_CLK_GATE_OVRE 0x554
+
+/* I2S registers to handle during APE MBIST WAR */
+#define TEGRA210_I2S_BASE  0x11000
+#define TEGRA210_I2S_SIZE  0x100
+#define TEGRA210_I2S_CTRLS 5
+#define TEGRA210_I2S_CG    0x88
+#define TEGRA210_I2S_CTRL  0xa0
+
+/* DISPA registers to handle during MBIST WAR */
+#define DC_CMD_DISPLAY_COMMAND 0xc8
+#define DC_COM_DSC_TOP_CTL 0xcf8
+
+/* VIC register to handle during MBIST WAR */
+#define NV_PVIC_THI_SLCG_OVERRIDE_LOW 0x8c
+
+/* APE, DISPA and VIC base addesses needed for MBIST WAR */
+#define TEGRA210_APE_BASE  0x702c0000
+#define TEGRA210_DISPA_BASE 0x54200000
+#define TEGRA210_VIC_BASE  0x54340000
+
 /*
  * SDM fractional divisor is 16-bit 2's complement signed number within
  * (-2^12 ... 2^12-1) range. Represented in PLL data structure as unsigned
@@ -256,8 +282,22 @@
 } tegra210_cpu_clk_sctx;
 #endif
 
+struct tegra210_domain_mbist_war {
+	int (*handle_lvl2_ovr)(struct tegra210_domain_mbist_war *mbist);
+	const u32 lvl2_offset;
+	const u32 lvl2_mask;
+	const unsigned int num_clks;
+	const unsigned int *clk_init_data;
+	struct clk_bulk_data *clks;
+};
+
+static struct clk **clks;
+
 static void __iomem *clk_base;
 static void __iomem *pmc_base;
+static void __iomem *ape_base;
+static void __iomem *dispa_base;
+static void __iomem *vic_base;
 
 static unsigned long osc_freq;
 static unsigned long pll_ref_freq;
@@ -268,6 +308,7 @@
 static DEFINE_SPINLOCK(pll_u_lock);
 static DEFINE_SPINLOCK(sor1_lock);
 static DEFINE_SPINLOCK(emc_lock);
+static DEFINE_MUTEX(lvl2_ovr_lock);
 
 /* possible OSC frequencies in Hz */
 static unsigned long tegra210_input_freq[] = {
@@ -311,6 +352,8 @@
 #define PLLA_MISC2_WRITE_MASK		0x06ffffff
 
 /* PLLD */
+#define PLLD_BASE_CSI_CLKSOURCE		(1 << 23)
+
 #define PLLD_MISC0_EN_SDM		(1 << 16)
 #define PLLD_MISC0_LOCK_OVERRIDE	(1 << 17)
 #define PLLD_MISC0_LOCK_ENABLE		(1 << 18)
@@ -514,6 +557,176 @@ void tegra210_set_sata_pll_seq_sw(bool state)
 }
 EXPORT_SYMBOL_GPL(tegra210_set_sata_pll_seq_sw);
 
+static int tegra210_generic_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 val;
+	int err;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	val = readl_relaxed(clk_base + mbist->lvl2_offset);
+	writel_relaxed(val | mbist->lvl2_mask, clk_base + mbist->lvl2_offset);
+	fence_udelay(1, clk_base);
+	writel_relaxed(val, clk_base + mbist->lvl2_offset);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_venc_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 csi_src, ovra, ovre;
+	int err;
+	unsigned long flags = 0;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+	spin_lock_irqsave(&pll_d_lock, flags);
+
+	csi_src = readl_relaxed(clk_base + PLLD_BASE);
+	writel_relaxed(csi_src | PLLD_BASE_CSI_CLKSOURCE, clk_base + PLLD_BASE);
+	fence_udelay(1, clk_base);
+
+	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
+	writel_relaxed(ovra | BIT(15), clk_base + LVL2_CLK_GATE_OVRA);
+	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(ovre | BIT(3), clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
+	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(csi_src, clk_base + PLLD_BASE);
+	fence_udelay(1, clk_base);
+
+	spin_unlock_irqrestore(&pll_d_lock, flags);
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_disp_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 ovra, dsc_top_ctrl;
+	int err;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
+	writel_relaxed(ovra | BIT(1), clk_base + LVL2_CLK_GATE_OVRA);
+	fence_udelay(1, clk_base);
+
+	dsc_top_ctrl = readl_relaxed(dispa_base + DC_COM_DSC_TOP_CTL);
+	writel_relaxed(dsc_top_ctrl | BIT(2), dispa_base + DC_COM_DSC_TOP_CTL);
+	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
+	writel_relaxed(dsc_top_ctrl, dispa_base + DC_COM_DSC_TOP_CTL);
+	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
+
+	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_vic_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	u32 ovre, val;
+	int err;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(ovre | BIT(5), clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	val = readl_relaxed(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+	writel_relaxed(val | BIT(0) | GENMASK(7, 2) | BIT(24),
+			vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+	fence_udelay(1, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+
+	writel_relaxed(val, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+	readl(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
+
+	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
+static int tegra210_ape_mbist_war(struct tegra210_domain_mbist_war *mbist)
+{
+	int err, i;
+	u32 ovrc, ovre;
+	void __iomem *i2s_base;
+
+	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&lvl2_ovr_lock);
+
+	ovrc = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRC);
+	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
+	writel_relaxed(ovrc | BIT(1), clk_base + LVL2_CLK_GATE_OVRC);
+	writel_relaxed(ovre | BIT(10) | BIT(11),
+			clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	i2s_base = ape_base + TEGRA210_I2S_BASE;
+	for (i = 0; i < TEGRA210_I2S_CTRLS; i++) {
+		u32 i2s_ctrl;
+
+		i2s_ctrl = readl_relaxed(i2s_base + TEGRA210_I2S_CTRL);
+		writel_relaxed(i2s_ctrl | BIT(10),
+				i2s_base + TEGRA210_I2S_CTRL);
+		writel_relaxed(0, i2s_base + TEGRA210_I2S_CG);
+		readl(i2s_base + TEGRA210_I2S_CG);
+		writel_relaxed(1, i2s_base + TEGRA210_I2S_CG);
+		writel_relaxed(i2s_ctrl, i2s_base + TEGRA210_I2S_CTRL);
+		readl(i2s_base + TEGRA210_I2S_CTRL);
+
+		i2s_base += TEGRA210_I2S_SIZE;
+	}
+
+	writel_relaxed(ovrc, clk_base + LVL2_CLK_GATE_OVRC);
+	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
+	fence_udelay(1, clk_base);
+
+	mutex_unlock(&lvl2_ovr_lock);
+
+	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
+
+	return 0;
+}
+
 static inline void _pll_misc_chk_default(void __iomem *base,
 					struct tegra_clk_pll_params *params,
 					u8 misc_num, u32 default_val, u32 mask)
@@ -2412,13 +2625,137 @@ struct utmi_clk_param {
 	{ "pll_a1", &pll_a1_params, tegra_clk_pll_a1, "pll_ref" },
 };
 
-static struct clk **clks;
-
 static const char * const aclk_parents[] = {
 	"pll_a1", "pll_c", "pll_p", "pll_a_out0", "pll_c2", "pll_c3",
 	"clk_m"
 };
 
+static const unsigned int nvjpg_slcg_clkids[] = { TEGRA210_CLK_NVDEC };
+static const unsigned int nvdec_slcg_clkids[] = { TEGRA210_CLK_NVJPG };
+static const unsigned int sor_slcg_clkids[] = { TEGRA210_CLK_HDA2CODEC_2X,
+	TEGRA210_CLK_HDA2HDMI, TEGRA210_CLK_DISP1, TEGRA210_CLK_DISP2 };
+static const unsigned int disp_slcg_clkids[] = { TEGRA210_CLK_LA,
+	TEGRA210_CLK_HOST1X};
+static const unsigned int xusba_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
+	TEGRA210_CLK_XUSB_DEV };
+static const unsigned int xusbb_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
+	TEGRA210_CLK_XUSB_SS };
+static const unsigned int xusbc_slcg_clkids[] = { TEGRA210_CLK_XUSB_DEV,
+	TEGRA210_CLK_XUSB_SS };
+static const unsigned int venc_slcg_clkids[] = { TEGRA210_CLK_HOST1X,
+	TEGRA210_CLK_PLL_D };
+static const unsigned int ape_slcg_clkids[] = { TEGRA210_CLK_ACLK,
+	TEGRA210_CLK_I2S0, TEGRA210_CLK_I2S1, TEGRA210_CLK_I2S2,
+	TEGRA210_CLK_I2S3, TEGRA210_CLK_I2S4, TEGRA210_CLK_SPDIF_OUT,
+	TEGRA210_CLK_D_AUDIO };
+static const unsigned int vic_slcg_clkids[] = { TEGRA210_CLK_HOST1X };
+
+static struct tegra210_domain_mbist_war tegra210_pg_mbist_war[] = {
+	[TEGRA_POWERGATE_VENC] = {
+		.handle_lvl2_ovr = tegra210_venc_mbist_war,
+		.num_clks = ARRAY_SIZE(venc_slcg_clkids),
+		.clk_init_data = venc_slcg_clkids,
+	},
+	[TEGRA_POWERGATE_SATA] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(0) | BIT(17) | BIT(19),
+	},
+	[TEGRA_POWERGATE_MPE] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRE,
+		.lvl2_mask = BIT(2),
+	},
+	[TEGRA_POWERGATE_SOR] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.num_clks = ARRAY_SIZE(sor_slcg_clkids),
+		.clk_init_data = sor_slcg_clkids,
+		.lvl2_offset = LVL2_CLK_GATE_OVRA,
+		.lvl2_mask = BIT(1) | BIT(2),
+	},
+	[TEGRA_POWERGATE_DIS] = {
+		.handle_lvl2_ovr = tegra210_disp_mbist_war,
+		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
+		.clk_init_data = disp_slcg_clkids,
+	},
+	[TEGRA_POWERGATE_DISB] = {
+		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
+		.clk_init_data = disp_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRA,
+		.lvl2_mask = BIT(2),
+	},
+	[TEGRA_POWERGATE_XUSBA] = {
+		.num_clks = ARRAY_SIZE(xusba_slcg_clkids),
+		.clk_init_data = xusba_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(30) | BIT(31),
+	},
+	[TEGRA_POWERGATE_XUSBB] = {
+		.num_clks = ARRAY_SIZE(xusbb_slcg_clkids),
+		.clk_init_data = xusbb_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(30) | BIT(31),
+	},
+	[TEGRA_POWERGATE_XUSBC] = {
+		.num_clks = ARRAY_SIZE(xusbc_slcg_clkids),
+		.clk_init_data = xusbc_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(30) | BIT(31),
+	},
+	[TEGRA_POWERGATE_VIC] = {
+		.num_clks = ARRAY_SIZE(vic_slcg_clkids),
+		.clk_init_data = vic_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_vic_mbist_war,
+	},
+	[TEGRA_POWERGATE_NVDEC] = {
+		.num_clks = ARRAY_SIZE(nvdec_slcg_clkids),
+		.clk_init_data = nvdec_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(9) | BIT(31),
+	},
+	[TEGRA_POWERGATE_NVJPG] = {
+		.num_clks = ARRAY_SIZE(nvjpg_slcg_clkids),
+		.clk_init_data = nvjpg_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRC,
+		.lvl2_mask = BIT(9) | BIT(31),
+	},
+	[TEGRA_POWERGATE_AUD] = {
+		.num_clks = ARRAY_SIZE(ape_slcg_clkids),
+		.clk_init_data = ape_slcg_clkids,
+		.handle_lvl2_ovr = tegra210_ape_mbist_war,
+	},
+	[TEGRA_POWERGATE_VE2] = {
+		.handle_lvl2_ovr = tegra210_generic_mbist_war,
+		.lvl2_offset = LVL2_CLK_GATE_OVRD,
+		.lvl2_mask = BIT(22),
+	},
+};
+
+void tegra210_clk_handle_mbist_war(unsigned int id)
+{
+	int err;
+	struct tegra210_domain_mbist_war *mbist_war;
+
+	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
+		WARN(1, "unknown domain id in MBIST WAR handler\n");
+		return;
+	}
+
+	mbist_war = &tegra210_pg_mbist_war[id];
+	if (!mbist_war->handle_lvl2_ovr)
+		return;
+
+	err = mbist_war->handle_lvl2_ovr(mbist_war);
+	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
+}
+
+
 void tegra210_put_utmipll_in_iddq(void)
 {
 	u32 reg;
@@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
 	return 0;
 }
 
+static void tegra210_mbist_clk_init(void)
+{
+	int i, j;
+
+	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
+		int num_clks = tegra210_pg_mbist_war[i].num_clks;
+		struct clk_bulk_data *clk_data;
+
+		if (!num_clks)
+			continue;
+
+		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
+					 GFP_KERNEL);
+		if (WARN(!clk_data,
+			"no space for MBIST WAR clk array for %d\n", i)) {
+			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
+			continue;
+		}
+
+		tegra210_pg_mbist_war[i].clks = clk_data;
+		for (j = 0; j < num_clks; j++) {
+			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
+			struct clk *clk = clks[clk_id];
+
+			if (IS_ERR(clk)) {
+				clk_data[j].clk = NULL;
+				WARN(1, "clk_id: %d\n", clk_id);
+			} else {
+				clk_data[j].clk = clk;
+			}
+		}
+	}
+}
+
 /**
  * tegra210_clock_init - Tegra210-specific clock initialization
  * @np: struct device_node * of the DT node for the SoC CAR IP block
@@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
 		return;
 	}
 
+	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
+	if (!ape_base) {
+		pr_err("ioremap tegra210 APE failed\n");
+		return;
+	}
+
+	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
+	if (!dispa_base) {
+		pr_err("ioremap tegra210 DISPA failed\n");
+		return;
+	}
+
+	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
+	if (!vic_base) {
+		pr_err("ioremap tegra210 VIC failed\n");
+		return;
+	}
+
 	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
 			      TEGRA210_CAR_BANK_COUNT);
 	if (!clks)
@@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
 	tegra_add_of_provider(np);
 	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
 
+	tegra210_mbist_clk_init();
+
 	tegra_cpu_car_ops = &tegra210_cpu_car_ops;
 }
 CLK_OF_DECLARE(tegra210, "nvidia,tegra210-car", tegra210_clock_init);
diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
index d23c9cf..a3d46f7 100644
--- a/include/linux/clk/tegra.h
+++ b/include/linux/clk/tegra.h
@@ -128,5 +128,10 @@ static inline void tegra_cpu_clock_resume(void)
 extern void tegra210_set_sata_pll_seq_sw(bool state);
 extern void tegra210_put_utmipll_in_iddq(void);
 extern void tegra210_put_utmipll_out_iddq(void);
+#ifndef CONFIG_ARCH_TEGRA_210_SOC
+static inline void tegra210_clk_handle_mbist_war(unsigned int id) {}
+#else
+extern void tegra210_clk_handle_mbist_war(unsigned int id);
+#endif
 
 #endif /* __LINUX_CLK_TEGRA_H_ */
-- 
1.9.1

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> Tegra210 has a hw bug which can cause IP blocks to lock up when ungating a
> domain. The reason is that the logic responsible for resetting the memory
> built-in self test mode can come up in an undefined state because its
> clock is gated by a second level clock gate (SLCG). Work around this by
> making sure the logic will get some clock edges by ensuring the relevant
> clock is enabled and temporarily override the relevant SLCGs.
> Unfortunately for some IP blocks, the control bits for overriding the
> SLCGs are not in CAR, but in the IP block itself. This means we need to
> map a few extra register banks in the clock code.
> 
> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/clk/tegra/clk-tegra210.c | 395 ++++++++++++++++++++++++++++++++++++++-
>  include/linux/clk/tegra.h        |   5 +
>  2 files changed, 398 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> index f790c2d..f61ec1f 100644
> --- a/drivers/clk/tegra/clk-tegra210.c
> +++ b/drivers/clk/tegra/clk-tegra210.c
> @@ -22,10 +22,12 @@
>  #include <linux/of_address.h>
>  #include <linux/delay.h>
>  #include <linux/export.h>
> +#include <linux/mutex.h>
>  #include <linux/clk/tegra.h>
>  #include <dt-bindings/clock/tegra210-car.h>
>  #include <dt-bindings/reset/tegra210-car.h>
>  #include <linux/iopoll.h>
> +#include <soc/tegra/pmc.h>
>  
>  #include "clk.h"
>  #include "clk-id.h"
> @@ -232,6 +234,30 @@
>  #define CLK_RST_CONTROLLER_RST_DEV_Y_SET 0x2a8
>  #define CLK_RST_CONTROLLER_RST_DEV_Y_CLR 0x2ac
>  
> +#define LVL2_CLK_GATE_OVRA 0xf8
> +#define LVL2_CLK_GATE_OVRC 0x3a0
> +#define LVL2_CLK_GATE_OVRD 0x3a4
> +#define LVL2_CLK_GATE_OVRE 0x554
> +
> +/* I2S registers to handle during APE MBIST WAR */
> +#define TEGRA210_I2S_BASE  0x11000
> +#define TEGRA210_I2S_SIZE  0x100
> +#define TEGRA210_I2S_CTRLS 5
> +#define TEGRA210_I2S_CG    0x88
> +#define TEGRA210_I2S_CTRL  0xa0
> +
> +/* DISPA registers to handle during MBIST WAR */
> +#define DC_CMD_DISPLAY_COMMAND 0xc8
> +#define DC_COM_DSC_TOP_CTL 0xcf8
> +
> +/* VIC register to handle during MBIST WAR */
> +#define NV_PVIC_THI_SLCG_OVERRIDE_LOW 0x8c
> +
> +/* APE, DISPA and VIC base addesses needed for MBIST WAR */
> +#define TEGRA210_APE_BASE  0x702c0000

Nit-pick, I think that it is only necessary to map the AHUB here as the
I2S are a sub-device of this. So we only need to map 0x702d0000-0x702dffff.

> +#define TEGRA210_DISPA_BASE 0x54200000
> +#define TEGRA210_VIC_BASE  0x54340000
> +
>  /*
>   * SDM fractional divisor is 16-bit 2's complement signed number within
>   * (-2^12 ... 2^12-1) range. Represented in PLL data structure as unsigned
> @@ -256,8 +282,22 @@
>  } tegra210_cpu_clk_sctx;
>  #endif
>  
> +struct tegra210_domain_mbist_war {
> +	int (*handle_lvl2_ovr)(struct tegra210_domain_mbist_war *mbist);
> +	const u32 lvl2_offset;
> +	const u32 lvl2_mask;
> +	const unsigned int num_clks;
> +	const unsigned int *clk_init_data;
> +	struct clk_bulk_data *clks;
> +};
> +
> +static struct clk **clks;
> +
>  static void __iomem *clk_base;
>  static void __iomem *pmc_base;
> +static void __iomem *ape_base;
> +static void __iomem *dispa_base;
> +static void __iomem *vic_base;
>  
>  static unsigned long osc_freq;
>  static unsigned long pll_ref_freq;
> @@ -268,6 +308,7 @@
>  static DEFINE_SPINLOCK(pll_u_lock);
>  static DEFINE_SPINLOCK(sor1_lock);
>  static DEFINE_SPINLOCK(emc_lock);
> +static DEFINE_MUTEX(lvl2_ovr_lock);
>  
>  /* possible OSC frequencies in Hz */
>  static unsigned long tegra210_input_freq[] = {
> @@ -311,6 +352,8 @@
>  #define PLLA_MISC2_WRITE_MASK		0x06ffffff
>  
>  /* PLLD */
> +#define PLLD_BASE_CSI_CLKSOURCE		(1 << 23)
> +
>  #define PLLD_MISC0_EN_SDM		(1 << 16)
>  #define PLLD_MISC0_LOCK_OVERRIDE	(1 << 17)
>  #define PLLD_MISC0_LOCK_ENABLE		(1 << 18)
> @@ -514,6 +557,176 @@ void tegra210_set_sata_pll_seq_sw(bool state)
>  }
>  EXPORT_SYMBOL_GPL(tegra210_set_sata_pll_seq_sw);
>  
> +static int tegra210_generic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 val;
> +	int err;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	val = readl_relaxed(clk_base + mbist->lvl2_offset);
> +	writel_relaxed(val | mbist->lvl2_mask, clk_base + mbist->lvl2_offset);
> +	fence_udelay(1, clk_base);
> +	writel_relaxed(val, clk_base + mbist->lvl2_offset);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_venc_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 csi_src, ovra, ovre;
> +	int err;
> +	unsigned long flags = 0;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +	spin_lock_irqsave(&pll_d_lock, flags);

Downstream does not appear to implement a spinlock around this code
AFAICT. With the delays it seems we are disabling interrupts for quite a
bit of time. If there is no other way to get around this then fine, but
I am curious if we need this? Are you worrying about the PLLD being
updated at the same time this is happening? Is that likely see that
devices using the PLLD will be waiting for the powerdomain to be enabled
first?

> +
> +	csi_src = readl_relaxed(clk_base + PLLD_BASE);
> +	writel_relaxed(csi_src | PLLD_BASE_CSI_CLKSOURCE, clk_base + PLLD_BASE);
> +	fence_udelay(1, clk_base);
> +
> +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> +	writel_relaxed(ovra | BIT(15), clk_base + LVL2_CLK_GATE_OVRA);
> +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(ovre | BIT(3), clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(csi_src, clk_base + PLLD_BASE);
> +	fence_udelay(1, clk_base);
> +
> +	spin_unlock_irqrestore(&pll_d_lock, flags);
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_disp_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 ovra, dsc_top_ctrl;
> +	int err;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> +	writel_relaxed(ovra | BIT(1), clk_base + LVL2_CLK_GATE_OVRA);
> +	fence_udelay(1, clk_base);
> +
> +	dsc_top_ctrl = readl_relaxed(dispa_base + DC_COM_DSC_TOP_CTL);
> +	writel_relaxed(dsc_top_ctrl | BIT(2), dispa_base + DC_COM_DSC_TOP_CTL);
> +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> +	writel_relaxed(dsc_top_ctrl, dispa_base + DC_COM_DSC_TOP_CTL);
> +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> +
> +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_vic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 ovre, val;
> +	int err;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(ovre | BIT(5), clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	val = readl_relaxed(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +	writel_relaxed(val | BIT(0) | GENMASK(7, 2) | BIT(24),
> +			vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +	fence_udelay(1, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +
> +	writel_relaxed(val, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +	readl(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +
> +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_ape_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	int err, i;
> +	u32 ovrc, ovre;
> +	void __iomem *i2s_base;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	ovrc = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRC);
> +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(ovrc | BIT(1), clk_base + LVL2_CLK_GATE_OVRC);
> +	writel_relaxed(ovre | BIT(10) | BIT(11),
> +			clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	i2s_base = ape_base + TEGRA210_I2S_BASE;
> +	for (i = 0; i < TEGRA210_I2S_CTRLS; i++) {
> +		u32 i2s_ctrl;
> +
> +		i2s_ctrl = readl_relaxed(i2s_base + TEGRA210_I2S_CTRL);
> +		writel_relaxed(i2s_ctrl | BIT(10),
> +				i2s_base + TEGRA210_I2S_CTRL);
> +		writel_relaxed(0, i2s_base + TEGRA210_I2S_CG);
> +		readl(i2s_base + TEGRA210_I2S_CG);
> +		writel_relaxed(1, i2s_base + TEGRA210_I2S_CG);
> +		writel_relaxed(i2s_ctrl, i2s_base + TEGRA210_I2S_CTRL);
> +		readl(i2s_base + TEGRA210_I2S_CTRL);
> +
> +		i2s_base += TEGRA210_I2S_SIZE;
> +	}
> +
> +	writel_relaxed(ovrc, clk_base + LVL2_CLK_GATE_OVRC);
> +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
>  static inline void _pll_misc_chk_default(void __iomem *base,
>  					struct tegra_clk_pll_params *params,
>  					u8 misc_num, u32 default_val, u32 mask)
> @@ -2412,13 +2625,137 @@ struct utmi_clk_param {
>  	{ "pll_a1", &pll_a1_params, tegra_clk_pll_a1, "pll_ref" },
>  };
>  
> -static struct clk **clks;
> -
>  static const char * const aclk_parents[] = {
>  	"pll_a1", "pll_c", "pll_p", "pll_a_out0", "pll_c2", "pll_c3",
>  	"clk_m"
>  };
>  
> +static const unsigned int nvjpg_slcg_clkids[] = { TEGRA210_CLK_NVDEC };
> +static const unsigned int nvdec_slcg_clkids[] = { TEGRA210_CLK_NVJPG };
> +static const unsigned int sor_slcg_clkids[] = { TEGRA210_CLK_HDA2CODEC_2X,
> +	TEGRA210_CLK_HDA2HDMI, TEGRA210_CLK_DISP1, TEGRA210_CLK_DISP2 };
> +static const unsigned int disp_slcg_clkids[] = { TEGRA210_CLK_LA,
> +	TEGRA210_CLK_HOST1X};
> +static const unsigned int xusba_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> +	TEGRA210_CLK_XUSB_DEV };
> +static const unsigned int xusbb_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> +	TEGRA210_CLK_XUSB_SS };
> +static const unsigned int xusbc_slcg_clkids[] = { TEGRA210_CLK_XUSB_DEV,
> +	TEGRA210_CLK_XUSB_SS };
> +static const unsigned int venc_slcg_clkids[] = { TEGRA210_CLK_HOST1X,
> +	TEGRA210_CLK_PLL_D };
> +static const unsigned int ape_slcg_clkids[] = { TEGRA210_CLK_ACLK,
> +	TEGRA210_CLK_I2S0, TEGRA210_CLK_I2S1, TEGRA210_CLK_I2S2,
> +	TEGRA210_CLK_I2S3, TEGRA210_CLK_I2S4, TEGRA210_CLK_SPDIF_OUT,
> +	TEGRA210_CLK_D_AUDIO };
> +static const unsigned int vic_slcg_clkids[] = { TEGRA210_CLK_HOST1X };
> +
> +static struct tegra210_domain_mbist_war tegra210_pg_mbist_war[] = {
> +	[TEGRA_POWERGATE_VENC] = {
> +		.handle_lvl2_ovr = tegra210_venc_mbist_war,
> +		.num_clks = ARRAY_SIZE(venc_slcg_clkids),
> +		.clk_init_data = venc_slcg_clkids,
> +	},
> +	[TEGRA_POWERGATE_SATA] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(0) | BIT(17) | BIT(19),
> +	},
> +	[TEGRA_POWERGATE_MPE] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRE,
> +		.lvl2_mask = BIT(2),
> +	},
> +	[TEGRA_POWERGATE_SOR] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.num_clks = ARRAY_SIZE(sor_slcg_clkids),
> +		.clk_init_data = sor_slcg_clkids,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> +		.lvl2_mask = BIT(1) | BIT(2),
> +	},
> +	[TEGRA_POWERGATE_DIS] = {
> +		.handle_lvl2_ovr = tegra210_disp_mbist_war,
> +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> +		.clk_init_data = disp_slcg_clkids,
> +	},
> +	[TEGRA_POWERGATE_DISB] = {
> +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> +		.clk_init_data = disp_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> +		.lvl2_mask = BIT(2),
> +	},
> +	[TEGRA_POWERGATE_XUSBA] = {
> +		.num_clks = ARRAY_SIZE(xusba_slcg_clkids),
> +		.clk_init_data = xusba_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(30) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_XUSBB] = {
> +		.num_clks = ARRAY_SIZE(xusbb_slcg_clkids),
> +		.clk_init_data = xusbb_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(30) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_XUSBC] = {
> +		.num_clks = ARRAY_SIZE(xusbc_slcg_clkids),
> +		.clk_init_data = xusbc_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(30) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_VIC] = {
> +		.num_clks = ARRAY_SIZE(vic_slcg_clkids),
> +		.clk_init_data = vic_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_vic_mbist_war,
> +	},
> +	[TEGRA_POWERGATE_NVDEC] = {
> +		.num_clks = ARRAY_SIZE(nvdec_slcg_clkids),
> +		.clk_init_data = nvdec_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(9) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_NVJPG] = {
> +		.num_clks = ARRAY_SIZE(nvjpg_slcg_clkids),
> +		.clk_init_data = nvjpg_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(9) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_AUD] = {
> +		.num_clks = ARRAY_SIZE(ape_slcg_clkids),
> +		.clk_init_data = ape_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_ape_mbist_war,
> +	},
> +	[TEGRA_POWERGATE_VE2] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRD,
> +		.lvl2_mask = BIT(22),
> +	},
> +};
> +
> +void tegra210_clk_handle_mbist_war(unsigned int id)
> +{
> +	int err;
> +	struct tegra210_domain_mbist_war *mbist_war;
> +
> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
> +		return;
> +	}
> +
> +	mbist_war = &tegra210_pg_mbist_war[id];
> +	if (!mbist_war->handle_lvl2_ovr)
> +		return;
> +
> +	err = mbist_war->handle_lvl2_ovr(mbist_war);

Why not move the clk_bulk_prepare_enable/disable_unprepare and
mutex_lock/unlock functions into this function around the call to
->handle_lvl2_ovr to save the duplication of that code in each of the
war functions?

> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
> +}

I think that the above function should return an error and we should let
the power-domain power-on fail.

> +
> +
>  void tegra210_put_utmipll_in_iddq(void)
>  {
>  	u32 reg;
> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
>  	return 0;
>  }
>  
> +static void tegra210_mbist_clk_init(void)
> +{
> +	int i, j;
> +
> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
> +		struct clk_bulk_data *clk_data;
> +
> +		if (!num_clks)
> +			continue;
> +
> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
> +					 GFP_KERNEL);
> +		if (WARN(!clk_data,
> +			"no space for MBIST WAR clk array for %d\n", i)) {
> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
> +			continue;
> +		}

Printing error messages on memory allocation failures are not needed and
have been removed from various drivers. So lets no add any error
messages or warnings here.

Also I think that we should just return an error here and not bother
continuing as there is no point.

> +
> +		tegra210_pg_mbist_war[i].clks = clk_data;

I think that you should only populate this when all the clocks have been
initialised correctly. You could then use this to check the clocks have
been setup correctly when executing the war.

> +		for (j = 0; j < num_clks; j++) {
> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
> +			struct clk *clk = clks[clk_id];
> +
> +			if (IS_ERR(clk)) {
> +				clk_data[j].clk = NULL;
> +				WARN(1, "clk_id: %d\n", clk_id);

I think that we should return an error here.

> +			} else {
> +				clk_data[j].clk = clk;
> +			}
> +		}
> +	}
> +}
> +
>  /**
>   * tegra210_clock_init - Tegra210-specific clock initialization
>   * @np: struct device_node * of the DT node for the SoC CAR IP block
> @@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
>  		return;
>  	}
>  
> +	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
> +	if (!ape_base) {
> +		pr_err("ioremap tegra210 APE failed\n");
> +		return;
> +	}
> +
> +	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
> +	if (!dispa_base) {
> +		pr_err("ioremap tegra210 DISPA failed\n");
> +		return;
> +	}
> +
> +	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
> +	if (!vic_base) {
> +		pr_err("ioremap tegra210 VIC failed\n");
> +		return;
> +	}
> +
>  	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
>  			      TEGRA210_CAR_BANK_COUNT);
>  	if (!clks)
> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
>  	tegra_add_of_provider(np);
>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
>  
> +	tegra210_mbist_clk_init();
> +

Maybe add a print here if the mbist init fails and return. I understand
it may not be a critical failure but it should never fail.

>  	tegra_cpu_car_ops = &tegra210_cpu_car_ops;
>  }
>  CLK_OF_DECLARE(tegra210, "nvidia,tegra210-car", tegra210_clock_init);
> diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
> index d23c9cf..a3d46f7 100644
> --- a/include/linux/clk/tegra.h
> +++ b/include/linux/clk/tegra.h
> @@ -128,5 +128,10 @@ static inline void tegra_cpu_clock_resume(void)
>  extern void tegra210_set_sata_pll_seq_sw(bool state);
>  extern void tegra210_put_utmipll_in_iddq(void);
>  extern void tegra210_put_utmipll_out_iddq(void);
> +#ifndef CONFIG_ARCH_TEGRA_210_SOC
> +static inline void tegra210_clk_handle_mbist_war(unsigned int id) {}
> +#else
> +extern void tegra210_clk_handle_mbist_war(unsigned int id);
> +#endif
>  
>  #endif /* __LINUX_CLK_TEGRA_H_ */

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> Tegra210 has a hw bug which can cause IP blocks to lock up when ungating a
> domain. The reason is that the logic responsible for resetting the memory
> built-in self test mode can come up in an undefined state because its
> clock is gated by a second level clock gate (SLCG). Work around this by
> making sure the logic will get some clock edges by ensuring the relevant
> clock is enabled and temporarily override the relevant SLCGs.
> Unfortunately for some IP blocks, the control bits for overriding the
> SLCGs are not in CAR, but in the IP block itself. This means we need to
> map a few extra register banks in the clock code.
> 
> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/clk/tegra/clk-tegra210.c | 395 ++++++++++++++++++++++++++++++++++++++-
>  include/linux/clk/tegra.h        |   5 +
>  2 files changed, 398 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> index f790c2d..f61ec1f 100644
> --- a/drivers/clk/tegra/clk-tegra210.c
> +++ b/drivers/clk/tegra/clk-tegra210.c
> @@ -22,10 +22,12 @@
>  #include <linux/of_address.h>
>  #include <linux/delay.h>
>  #include <linux/export.h>
> +#include <linux/mutex.h>
>  #include <linux/clk/tegra.h>
>  #include <dt-bindings/clock/tegra210-car.h>
>  #include <dt-bindings/reset/tegra210-car.h>
>  #include <linux/iopoll.h>
> +#include <soc/tegra/pmc.h>
>  
>  #include "clk.h"
>  #include "clk-id.h"
> @@ -232,6 +234,30 @@
>  #define CLK_RST_CONTROLLER_RST_DEV_Y_SET 0x2a8
>  #define CLK_RST_CONTROLLER_RST_DEV_Y_CLR 0x2ac
>  
> +#define LVL2_CLK_GATE_OVRA 0xf8
> +#define LVL2_CLK_GATE_OVRC 0x3a0
> +#define LVL2_CLK_GATE_OVRD 0x3a4
> +#define LVL2_CLK_GATE_OVRE 0x554
> +
> +/* I2S registers to handle during APE MBIST WAR */
> +#define TEGRA210_I2S_BASE  0x11000
> +#define TEGRA210_I2S_SIZE  0x100
> +#define TEGRA210_I2S_CTRLS 5
> +#define TEGRA210_I2S_CG    0x88
> +#define TEGRA210_I2S_CTRL  0xa0
> +
> +/* DISPA registers to handle during MBIST WAR */
> +#define DC_CMD_DISPLAY_COMMAND 0xc8
> +#define DC_COM_DSC_TOP_CTL 0xcf8
> +
> +/* VIC register to handle during MBIST WAR */
> +#define NV_PVIC_THI_SLCG_OVERRIDE_LOW 0x8c
> +
> +/* APE, DISPA and VIC base addesses needed for MBIST WAR */
> +#define TEGRA210_APE_BASE  0x702c0000

Nit-pick, I think that it is only necessary to map the AHUB here as the
I2S are a sub-device of this. So we only need to map 0x702d0000-0x702dffff.

> +#define TEGRA210_DISPA_BASE 0x54200000
> +#define TEGRA210_VIC_BASE  0x54340000
> +
>  /*
>   * SDM fractional divisor is 16-bit 2's complement signed number within
>   * (-2^12 ... 2^12-1) range. Represented in PLL data structure as unsigned
> @@ -256,8 +282,22 @@
>  } tegra210_cpu_clk_sctx;
>  #endif
>  
> +struct tegra210_domain_mbist_war {
> +	int (*handle_lvl2_ovr)(struct tegra210_domain_mbist_war *mbist);
> +	const u32 lvl2_offset;
> +	const u32 lvl2_mask;
> +	const unsigned int num_clks;
> +	const unsigned int *clk_init_data;
> +	struct clk_bulk_data *clks;
> +};
> +
> +static struct clk **clks;
> +
>  static void __iomem *clk_base;
>  static void __iomem *pmc_base;
> +static void __iomem *ape_base;
> +static void __iomem *dispa_base;
> +static void __iomem *vic_base;
>  
>  static unsigned long osc_freq;
>  static unsigned long pll_ref_freq;
> @@ -268,6 +308,7 @@
>  static DEFINE_SPINLOCK(pll_u_lock);
>  static DEFINE_SPINLOCK(sor1_lock);
>  static DEFINE_SPINLOCK(emc_lock);
> +static DEFINE_MUTEX(lvl2_ovr_lock);
>  
>  /* possible OSC frequencies in Hz */
>  static unsigned long tegra210_input_freq[] = {
> @@ -311,6 +352,8 @@
>  #define PLLA_MISC2_WRITE_MASK		0x06ffffff
>  
>  /* PLLD */
> +#define PLLD_BASE_CSI_CLKSOURCE		(1 << 23)
> +
>  #define PLLD_MISC0_EN_SDM		(1 << 16)
>  #define PLLD_MISC0_LOCK_OVERRIDE	(1 << 17)
>  #define PLLD_MISC0_LOCK_ENABLE		(1 << 18)
> @@ -514,6 +557,176 @@ void tegra210_set_sata_pll_seq_sw(bool state)
>  }
>  EXPORT_SYMBOL_GPL(tegra210_set_sata_pll_seq_sw);
>  
> +static int tegra210_generic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 val;
> +	int err;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	val = readl_relaxed(clk_base + mbist->lvl2_offset);
> +	writel_relaxed(val | mbist->lvl2_mask, clk_base + mbist->lvl2_offset);
> +	fence_udelay(1, clk_base);
> +	writel_relaxed(val, clk_base + mbist->lvl2_offset);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_venc_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 csi_src, ovra, ovre;
> +	int err;
> +	unsigned long flags = 0;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +	spin_lock_irqsave(&pll_d_lock, flags);

Downstream does not appear to implement a spinlock around this code
AFAICT. With the delays it seems we are disabling interrupts for quite a
bit of time. If there is no other way to get around this then fine, but
I am curious if we need this? Are you worrying about the PLLD being
updated at the same time this is happening? Is that likely see that
devices using the PLLD will be waiting for the powerdomain to be enabled
first?

> +
> +	csi_src = readl_relaxed(clk_base + PLLD_BASE);
> +	writel_relaxed(csi_src | PLLD_BASE_CSI_CLKSOURCE, clk_base + PLLD_BASE);
> +	fence_udelay(1, clk_base);
> +
> +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> +	writel_relaxed(ovra | BIT(15), clk_base + LVL2_CLK_GATE_OVRA);
> +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(ovre | BIT(3), clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(csi_src, clk_base + PLLD_BASE);
> +	fence_udelay(1, clk_base);
> +
> +	spin_unlock_irqrestore(&pll_d_lock, flags);
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_disp_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 ovra, dsc_top_ctrl;
> +	int err;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> +	writel_relaxed(ovra | BIT(1), clk_base + LVL2_CLK_GATE_OVRA);
> +	fence_udelay(1, clk_base);
> +
> +	dsc_top_ctrl = readl_relaxed(dispa_base + DC_COM_DSC_TOP_CTL);
> +	writel_relaxed(dsc_top_ctrl | BIT(2), dispa_base + DC_COM_DSC_TOP_CTL);
> +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> +	writel_relaxed(dsc_top_ctrl, dispa_base + DC_COM_DSC_TOP_CTL);
> +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> +
> +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_vic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	u32 ovre, val;
> +	int err;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(ovre | BIT(5), clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	val = readl_relaxed(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +	writel_relaxed(val | BIT(0) | GENMASK(7, 2) | BIT(24),
> +			vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +	fence_udelay(1, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +
> +	writel_relaxed(val, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +	readl(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> +
> +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
> +static int tegra210_ape_mbist_war(struct tegra210_domain_mbist_war *mbist)
> +{
> +	int err, i;
> +	u32 ovrc, ovre;
> +	void __iomem *i2s_base;
> +
> +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> +	if (err < 0)
> +		return err;
> +
> +	mutex_lock(&lvl2_ovr_lock);
> +
> +	ovrc = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRC);
> +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> +	writel_relaxed(ovrc | BIT(1), clk_base + LVL2_CLK_GATE_OVRC);
> +	writel_relaxed(ovre | BIT(10) | BIT(11),
> +			clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	i2s_base = ape_base + TEGRA210_I2S_BASE;
> +	for (i = 0; i < TEGRA210_I2S_CTRLS; i++) {
> +		u32 i2s_ctrl;
> +
> +		i2s_ctrl = readl_relaxed(i2s_base + TEGRA210_I2S_CTRL);
> +		writel_relaxed(i2s_ctrl | BIT(10),
> +				i2s_base + TEGRA210_I2S_CTRL);
> +		writel_relaxed(0, i2s_base + TEGRA210_I2S_CG);
> +		readl(i2s_base + TEGRA210_I2S_CG);
> +		writel_relaxed(1, i2s_base + TEGRA210_I2S_CG);
> +		writel_relaxed(i2s_ctrl, i2s_base + TEGRA210_I2S_CTRL);
> +		readl(i2s_base + TEGRA210_I2S_CTRL);
> +
> +		i2s_base += TEGRA210_I2S_SIZE;
> +	}
> +
> +	writel_relaxed(ovrc, clk_base + LVL2_CLK_GATE_OVRC);
> +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> +	fence_udelay(1, clk_base);
> +
> +	mutex_unlock(&lvl2_ovr_lock);
> +
> +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> +
> +	return 0;
> +}
> +
>  static inline void _pll_misc_chk_default(void __iomem *base,
>  					struct tegra_clk_pll_params *params,
>  					u8 misc_num, u32 default_val, u32 mask)
> @@ -2412,13 +2625,137 @@ struct utmi_clk_param {
>  	{ "pll_a1", &pll_a1_params, tegra_clk_pll_a1, "pll_ref" },
>  };
>  
> -static struct clk **clks;
> -
>  static const char * const aclk_parents[] = {
>  	"pll_a1", "pll_c", "pll_p", "pll_a_out0", "pll_c2", "pll_c3",
>  	"clk_m"
>  };
>  
> +static const unsigned int nvjpg_slcg_clkids[] = { TEGRA210_CLK_NVDEC };
> +static const unsigned int nvdec_slcg_clkids[] = { TEGRA210_CLK_NVJPG };
> +static const unsigned int sor_slcg_clkids[] = { TEGRA210_CLK_HDA2CODEC_2X,
> +	TEGRA210_CLK_HDA2HDMI, TEGRA210_CLK_DISP1, TEGRA210_CLK_DISP2 };
> +static const unsigned int disp_slcg_clkids[] = { TEGRA210_CLK_LA,
> +	TEGRA210_CLK_HOST1X};
> +static const unsigned int xusba_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> +	TEGRA210_CLK_XUSB_DEV };
> +static const unsigned int xusbb_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> +	TEGRA210_CLK_XUSB_SS };
> +static const unsigned int xusbc_slcg_clkids[] = { TEGRA210_CLK_XUSB_DEV,
> +	TEGRA210_CLK_XUSB_SS };
> +static const unsigned int venc_slcg_clkids[] = { TEGRA210_CLK_HOST1X,
> +	TEGRA210_CLK_PLL_D };
> +static const unsigned int ape_slcg_clkids[] = { TEGRA210_CLK_ACLK,
> +	TEGRA210_CLK_I2S0, TEGRA210_CLK_I2S1, TEGRA210_CLK_I2S2,
> +	TEGRA210_CLK_I2S3, TEGRA210_CLK_I2S4, TEGRA210_CLK_SPDIF_OUT,
> +	TEGRA210_CLK_D_AUDIO };
> +static const unsigned int vic_slcg_clkids[] = { TEGRA210_CLK_HOST1X };
> +
> +static struct tegra210_domain_mbist_war tegra210_pg_mbist_war[] = {
> +	[TEGRA_POWERGATE_VENC] = {
> +		.handle_lvl2_ovr = tegra210_venc_mbist_war,
> +		.num_clks = ARRAY_SIZE(venc_slcg_clkids),
> +		.clk_init_data = venc_slcg_clkids,
> +	},
> +	[TEGRA_POWERGATE_SATA] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(0) | BIT(17) | BIT(19),
> +	},
> +	[TEGRA_POWERGATE_MPE] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRE,
> +		.lvl2_mask = BIT(2),
> +	},
> +	[TEGRA_POWERGATE_SOR] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.num_clks = ARRAY_SIZE(sor_slcg_clkids),
> +		.clk_init_data = sor_slcg_clkids,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> +		.lvl2_mask = BIT(1) | BIT(2),
> +	},
> +	[TEGRA_POWERGATE_DIS] = {
> +		.handle_lvl2_ovr = tegra210_disp_mbist_war,
> +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> +		.clk_init_data = disp_slcg_clkids,
> +	},
> +	[TEGRA_POWERGATE_DISB] = {
> +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> +		.clk_init_data = disp_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> +		.lvl2_mask = BIT(2),
> +	},
> +	[TEGRA_POWERGATE_XUSBA] = {
> +		.num_clks = ARRAY_SIZE(xusba_slcg_clkids),
> +		.clk_init_data = xusba_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(30) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_XUSBB] = {
> +		.num_clks = ARRAY_SIZE(xusbb_slcg_clkids),
> +		.clk_init_data = xusbb_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(30) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_XUSBC] = {
> +		.num_clks = ARRAY_SIZE(xusbc_slcg_clkids),
> +		.clk_init_data = xusbc_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(30) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_VIC] = {
> +		.num_clks = ARRAY_SIZE(vic_slcg_clkids),
> +		.clk_init_data = vic_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_vic_mbist_war,
> +	},
> +	[TEGRA_POWERGATE_NVDEC] = {
> +		.num_clks = ARRAY_SIZE(nvdec_slcg_clkids),
> +		.clk_init_data = nvdec_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(9) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_NVJPG] = {
> +		.num_clks = ARRAY_SIZE(nvjpg_slcg_clkids),
> +		.clk_init_data = nvjpg_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> +		.lvl2_mask = BIT(9) | BIT(31),
> +	},
> +	[TEGRA_POWERGATE_AUD] = {
> +		.num_clks = ARRAY_SIZE(ape_slcg_clkids),
> +		.clk_init_data = ape_slcg_clkids,
> +		.handle_lvl2_ovr = tegra210_ape_mbist_war,
> +	},
> +	[TEGRA_POWERGATE_VE2] = {
> +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> +		.lvl2_offset = LVL2_CLK_GATE_OVRD,
> +		.lvl2_mask = BIT(22),
> +	},
> +};
> +
> +void tegra210_clk_handle_mbist_war(unsigned int id)
> +{
> +	int err;
> +	struct tegra210_domain_mbist_war *mbist_war;
> +
> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
> +		return;
> +	}
> +
> +	mbist_war = &tegra210_pg_mbist_war[id];
> +	if (!mbist_war->handle_lvl2_ovr)
> +		return;
> +
> +	err = mbist_war->handle_lvl2_ovr(mbist_war);

Why not move the clk_bulk_prepare_enable/disable_unprepare and
mutex_lock/unlock functions into this function around the call to
->handle_lvl2_ovr to save the duplication of that code in each of the
war functions?

> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
> +}

I think that the above function should return an error and we should let
the power-domain power-on fail.

> +
> +
>  void tegra210_put_utmipll_in_iddq(void)
>  {
>  	u32 reg;
> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
>  	return 0;
>  }
>  
> +static void tegra210_mbist_clk_init(void)
> +{
> +	int i, j;
> +
> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
> +		struct clk_bulk_data *clk_data;
> +
> +		if (!num_clks)
> +			continue;
> +
> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
> +					 GFP_KERNEL);
> +		if (WARN(!clk_data,
> +			"no space for MBIST WAR clk array for %d\n", i)) {
> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
> +			continue;
> +		}

Printing error messages on memory allocation failures are not needed and
have been removed from various drivers. So lets no add any error
messages or warnings here.

Also I think that we should just return an error here and not bother
continuing as there is no point.

> +
> +		tegra210_pg_mbist_war[i].clks = clk_data;

I think that you should only populate this when all the clocks have been
initialised correctly. You could then use this to check the clocks have
been setup correctly when executing the war.

> +		for (j = 0; j < num_clks; j++) {
> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
> +			struct clk *clk = clks[clk_id];
> +
> +			if (IS_ERR(clk)) {
> +				clk_data[j].clk = NULL;
> +				WARN(1, "clk_id: %d\n", clk_id);

I think that we should return an error here.

> +			} else {
> +				clk_data[j].clk = clk;
> +			}
> +		}
> +	}
> +}
> +
>  /**
>   * tegra210_clock_init - Tegra210-specific clock initialization
>   * @np: struct device_node * of the DT node for the SoC CAR IP block
> @@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
>  		return;
>  	}
>  
> +	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
> +	if (!ape_base) {
> +		pr_err("ioremap tegra210 APE failed\n");
> +		return;
> +	}
> +
> +	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
> +	if (!dispa_base) {
> +		pr_err("ioremap tegra210 DISPA failed\n");
> +		return;
> +	}
> +
> +	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
> +	if (!vic_base) {
> +		pr_err("ioremap tegra210 VIC failed\n");
> +		return;
> +	}
> +
>  	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
>  			      TEGRA210_CAR_BANK_COUNT);
>  	if (!clks)
> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
>  	tegra_add_of_provider(np);
>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
>  
> +	tegra210_mbist_clk_init();
> +

Maybe add a print here if the mbist init fails and return. I understand
it may not be a critical failure but it should never fail.

>  	tegra_cpu_car_ops = &tegra210_cpu_car_ops;
>  }
>  CLK_OF_DECLARE(tegra210, "nvidia,tegra210-car", tegra210_clock_init);
> diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
> index d23c9cf..a3d46f7 100644
> --- a/include/linux/clk/tegra.h
> +++ b/include/linux/clk/tegra.h
> @@ -128,5 +128,10 @@ static inline void tegra_cpu_clock_resume(void)
>  extern void tegra210_set_sata_pll_seq_sw(bool state);
>  extern void tegra210_put_utmipll_in_iddq(void);
>  extern void tegra210_put_utmipll_out_iddq(void);
> +#ifndef CONFIG_ARCH_TEGRA_210_SOC
> +static inline void tegra210_clk_handle_mbist_war(unsigned int id) {}
> +#else
> +extern void tegra210_clk_handle_mbist_war(unsigned int id);
> +#endif
>  
>  #endif /* __LINUX_CLK_TEGRA_H_ */

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Peter De Schrijver]

On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:
> 
> On 23/01/18 09:22, Peter De Schrijver wrote:
> > Tegra210 has a hw bug which can cause IP blocks to lock up when ungating a
> > domain. The reason is that the logic responsible for resetting the memory
> > built-in self test mode can come up in an undefined state because its
> > clock is gated by a second level clock gate (SLCG). Work around this by
> > making sure the logic will get some clock edges by ensuring the relevant
> > clock is enabled and temporarily override the relevant SLCGs.
> > Unfortunately for some IP blocks, the control bits for overriding the
> > SLCGs are not in CAR, but in the IP block itself. This means we need to
> > map a few extra register banks in the clock code.
> > 
> > Signed-off-by: Peter De Schrijver <pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> > ---
> >  drivers/clk/tegra/clk-tegra210.c | 395 ++++++++++++++++++++++++++++++++++++++-
> >  include/linux/clk/tegra.h        |   5 +
> >  2 files changed, 398 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> > index f790c2d..f61ec1f 100644
> > --- a/drivers/clk/tegra/clk-tegra210.c
> > +++ b/drivers/clk/tegra/clk-tegra210.c
> > @@ -22,10 +22,12 @@
> >  #include <linux/of_address.h>
> >  #include <linux/delay.h>
> >  #include <linux/export.h>
> > +#include <linux/mutex.h>
> >  #include <linux/clk/tegra.h>
> >  #include <dt-bindings/clock/tegra210-car.h>
> >  #include <dt-bindings/reset/tegra210-car.h>
> >  #include <linux/iopoll.h>
> > +#include <soc/tegra/pmc.h>
> >  
> >  #include "clk.h"
> >  #include "clk-id.h"
> > @@ -232,6 +234,30 @@
> >  #define CLK_RST_CONTROLLER_RST_DEV_Y_SET 0x2a8
> >  #define CLK_RST_CONTROLLER_RST_DEV_Y_CLR 0x2ac
> >  
> > +#define LVL2_CLK_GATE_OVRA 0xf8
> > +#define LVL2_CLK_GATE_OVRC 0x3a0
> > +#define LVL2_CLK_GATE_OVRD 0x3a4
> > +#define LVL2_CLK_GATE_OVRE 0x554
> > +
> > +/* I2S registers to handle during APE MBIST WAR */
> > +#define TEGRA210_I2S_BASE  0x11000
> > +#define TEGRA210_I2S_SIZE  0x100
> > +#define TEGRA210_I2S_CTRLS 5
> > +#define TEGRA210_I2S_CG    0x88
> > +#define TEGRA210_I2S_CTRL  0xa0
> > +
> > +/* DISPA registers to handle during MBIST WAR */
> > +#define DC_CMD_DISPLAY_COMMAND 0xc8
> > +#define DC_COM_DSC_TOP_CTL 0xcf8
> > +
> > +/* VIC register to handle during MBIST WAR */
> > +#define NV_PVIC_THI_SLCG_OVERRIDE_LOW 0x8c
> > +
> > +/* APE, DISPA and VIC base addesses needed for MBIST WAR */
> > +#define TEGRA210_APE_BASE  0x702c0000
> 
> Nit-pick, I think that it is only necessary to map the AHUB here as the
> I2S are a sub-device of this. So we only need to map 0x702d0000-0x702dffff.
> 
> > +#define TEGRA210_DISPA_BASE 0x54200000
> > +#define TEGRA210_VIC_BASE  0x54340000
> > +
> >  /*
> >   * SDM fractional divisor is 16-bit 2's complement signed number within
> >   * (-2^12 ... 2^12-1) range. Represented in PLL data structure as unsigned
> > @@ -256,8 +282,22 @@
> >  } tegra210_cpu_clk_sctx;
> >  #endif
> >  
> > +struct tegra210_domain_mbist_war {
> > +	int (*handle_lvl2_ovr)(struct tegra210_domain_mbist_war *mbist);
> > +	const u32 lvl2_offset;
> > +	const u32 lvl2_mask;
> > +	const unsigned int num_clks;
> > +	const unsigned int *clk_init_data;
> > +	struct clk_bulk_data *clks;
> > +};
> > +
> > +static struct clk **clks;
> > +
> >  static void __iomem *clk_base;
> >  static void __iomem *pmc_base;
> > +static void __iomem *ape_base;
> > +static void __iomem *dispa_base;
> > +static void __iomem *vic_base;
> >  
> >  static unsigned long osc_freq;
> >  static unsigned long pll_ref_freq;
> > @@ -268,6 +308,7 @@
> >  static DEFINE_SPINLOCK(pll_u_lock);
> >  static DEFINE_SPINLOCK(sor1_lock);
> >  static DEFINE_SPINLOCK(emc_lock);
> > +static DEFINE_MUTEX(lvl2_ovr_lock);
> >  
> >  /* possible OSC frequencies in Hz */
> >  static unsigned long tegra210_input_freq[] = {
> > @@ -311,6 +352,8 @@
> >  #define PLLA_MISC2_WRITE_MASK		0x06ffffff
> >  
> >  /* PLLD */
> > +#define PLLD_BASE_CSI_CLKSOURCE		(1 << 23)
> > +
> >  #define PLLD_MISC0_EN_SDM		(1 << 16)
> >  #define PLLD_MISC0_LOCK_OVERRIDE	(1 << 17)
> >  #define PLLD_MISC0_LOCK_ENABLE		(1 << 18)
> > @@ -514,6 +557,176 @@ void tegra210_set_sata_pll_seq_sw(bool state)
> >  }
> >  EXPORT_SYMBOL_GPL(tegra210_set_sata_pll_seq_sw);
> >  
> > +static int tegra210_generic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 val;
> > +	int err;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	val = readl_relaxed(clk_base + mbist->lvl2_offset);
> > +	writel_relaxed(val | mbist->lvl2_mask, clk_base + mbist->lvl2_offset);
> > +	fence_udelay(1, clk_base);
> > +	writel_relaxed(val, clk_base + mbist->lvl2_offset);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_venc_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 csi_src, ovra, ovre;
> > +	int err;
> > +	unsigned long flags = 0;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +	spin_lock_irqsave(&pll_d_lock, flags);
> 
> Downstream does not appear to implement a spinlock around this code
> AFAICT. With the delays it seems we are disabling interrupts for quite a
> bit of time. If there is no other way to get around this then fine, but
> I am curious if we need this? Are you worrying about the PLLD being
> updated at the same time this is happening? Is that likely see that

Yes. We have to be sure the CSI source is not reset to 'brick'. That would
be the clock recovered from the CSI input signal, which is likely to be
missing. So effectively there would be no clock pulses then.

> devices using the PLLD will be waiting for the powerdomain to be enabled
> first?
> 

Hopefully not, but if they would, the resulting random hangs of the IP block
wouldn't be easy to trace back to accidental changes of the CSI source during
this WAR procedure.

> > +
> > +	csi_src = readl_relaxed(clk_base + PLLD_BASE);
> > +	writel_relaxed(csi_src | PLLD_BASE_CSI_CLKSOURCE, clk_base + PLLD_BASE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> > +	writel_relaxed(ovra | BIT(15), clk_base + LVL2_CLK_GATE_OVRA);
> > +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(ovre | BIT(3), clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> > +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(csi_src, clk_base + PLLD_BASE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	spin_unlock_irqrestore(&pll_d_lock, flags);
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_disp_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 ovra, dsc_top_ctrl;
> > +	int err;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> > +	writel_relaxed(ovra | BIT(1), clk_base + LVL2_CLK_GATE_OVRA);
> > +	fence_udelay(1, clk_base);
> > +
> > +	dsc_top_ctrl = readl_relaxed(dispa_base + DC_COM_DSC_TOP_CTL);
> > +	writel_relaxed(dsc_top_ctrl | BIT(2), dispa_base + DC_COM_DSC_TOP_CTL);
> > +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> > +	writel_relaxed(dsc_top_ctrl, dispa_base + DC_COM_DSC_TOP_CTL);
> > +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> > +
> > +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_vic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 ovre, val;
> > +	int err;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(ovre | BIT(5), clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	val = readl_relaxed(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +	writel_relaxed(val | BIT(0) | GENMASK(7, 2) | BIT(24),
> > +			vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +	fence_udelay(1, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +
> > +	writel_relaxed(val, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +	readl(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +
> > +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_ape_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	int err, i;
> > +	u32 ovrc, ovre;
> > +	void __iomem *i2s_base;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	ovrc = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRC);
> > +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(ovrc | BIT(1), clk_base + LVL2_CLK_GATE_OVRC);
> > +	writel_relaxed(ovre | BIT(10) | BIT(11),
> > +			clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	i2s_base = ape_base + TEGRA210_I2S_BASE;
> > +	for (i = 0; i < TEGRA210_I2S_CTRLS; i++) {
> > +		u32 i2s_ctrl;
> > +
> > +		i2s_ctrl = readl_relaxed(i2s_base + TEGRA210_I2S_CTRL);
> > +		writel_relaxed(i2s_ctrl | BIT(10),
> > +				i2s_base + TEGRA210_I2S_CTRL);
> > +		writel_relaxed(0, i2s_base + TEGRA210_I2S_CG);
> > +		readl(i2s_base + TEGRA210_I2S_CG);
> > +		writel_relaxed(1, i2s_base + TEGRA210_I2S_CG);
> > +		writel_relaxed(i2s_ctrl, i2s_base + TEGRA210_I2S_CTRL);
> > +		readl(i2s_base + TEGRA210_I2S_CTRL);
> > +
> > +		i2s_base += TEGRA210_I2S_SIZE;
> > +	}
> > +
> > +	writel_relaxed(ovrc, clk_base + LVL2_CLK_GATE_OVRC);
> > +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> >  static inline void _pll_misc_chk_default(void __iomem *base,
> >  					struct tegra_clk_pll_params *params,
> >  					u8 misc_num, u32 default_val, u32 mask)
> > @@ -2412,13 +2625,137 @@ struct utmi_clk_param {
> >  	{ "pll_a1", &pll_a1_params, tegra_clk_pll_a1, "pll_ref" },
> >  };
> >  
> > -static struct clk **clks;
> > -
> >  static const char * const aclk_parents[] = {
> >  	"pll_a1", "pll_c", "pll_p", "pll_a_out0", "pll_c2", "pll_c3",
> >  	"clk_m"
> >  };
> >  
> > +static const unsigned int nvjpg_slcg_clkids[] = { TEGRA210_CLK_NVDEC };
> > +static const unsigned int nvdec_slcg_clkids[] = { TEGRA210_CLK_NVJPG };
> > +static const unsigned int sor_slcg_clkids[] = { TEGRA210_CLK_HDA2CODEC_2X,
> > +	TEGRA210_CLK_HDA2HDMI, TEGRA210_CLK_DISP1, TEGRA210_CLK_DISP2 };
> > +static const unsigned int disp_slcg_clkids[] = { TEGRA210_CLK_LA,
> > +	TEGRA210_CLK_HOST1X};
> > +static const unsigned int xusba_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> > +	TEGRA210_CLK_XUSB_DEV };
> > +static const unsigned int xusbb_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> > +	TEGRA210_CLK_XUSB_SS };
> > +static const unsigned int xusbc_slcg_clkids[] = { TEGRA210_CLK_XUSB_DEV,
> > +	TEGRA210_CLK_XUSB_SS };
> > +static const unsigned int venc_slcg_clkids[] = { TEGRA210_CLK_HOST1X,
> > +	TEGRA210_CLK_PLL_D };
> > +static const unsigned int ape_slcg_clkids[] = { TEGRA210_CLK_ACLK,
> > +	TEGRA210_CLK_I2S0, TEGRA210_CLK_I2S1, TEGRA210_CLK_I2S2,
> > +	TEGRA210_CLK_I2S3, TEGRA210_CLK_I2S4, TEGRA210_CLK_SPDIF_OUT,
> > +	TEGRA210_CLK_D_AUDIO };
> > +static const unsigned int vic_slcg_clkids[] = { TEGRA210_CLK_HOST1X };
> > +
> > +static struct tegra210_domain_mbist_war tegra210_pg_mbist_war[] = {
> > +	[TEGRA_POWERGATE_VENC] = {
> > +		.handle_lvl2_ovr = tegra210_venc_mbist_war,
> > +		.num_clks = ARRAY_SIZE(venc_slcg_clkids),
> > +		.clk_init_data = venc_slcg_clkids,
> > +	},
> > +	[TEGRA_POWERGATE_SATA] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(0) | BIT(17) | BIT(19),
> > +	},
> > +	[TEGRA_POWERGATE_MPE] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRE,
> > +		.lvl2_mask = BIT(2),
> > +	},
> > +	[TEGRA_POWERGATE_SOR] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.num_clks = ARRAY_SIZE(sor_slcg_clkids),
> > +		.clk_init_data = sor_slcg_clkids,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> > +		.lvl2_mask = BIT(1) | BIT(2),
> > +	},
> > +	[TEGRA_POWERGATE_DIS] = {
> > +		.handle_lvl2_ovr = tegra210_disp_mbist_war,
> > +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> > +		.clk_init_data = disp_slcg_clkids,
> > +	},
> > +	[TEGRA_POWERGATE_DISB] = {
> > +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> > +		.clk_init_data = disp_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> > +		.lvl2_mask = BIT(2),
> > +	},
> > +	[TEGRA_POWERGATE_XUSBA] = {
> > +		.num_clks = ARRAY_SIZE(xusba_slcg_clkids),
> > +		.clk_init_data = xusba_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(30) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_XUSBB] = {
> > +		.num_clks = ARRAY_SIZE(xusbb_slcg_clkids),
> > +		.clk_init_data = xusbb_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(30) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_XUSBC] = {
> > +		.num_clks = ARRAY_SIZE(xusbc_slcg_clkids),
> > +		.clk_init_data = xusbc_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(30) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_VIC] = {
> > +		.num_clks = ARRAY_SIZE(vic_slcg_clkids),
> > +		.clk_init_data = vic_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_vic_mbist_war,
> > +	},
> > +	[TEGRA_POWERGATE_NVDEC] = {
> > +		.num_clks = ARRAY_SIZE(nvdec_slcg_clkids),
> > +		.clk_init_data = nvdec_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(9) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_NVJPG] = {
> > +		.num_clks = ARRAY_SIZE(nvjpg_slcg_clkids),
> > +		.clk_init_data = nvjpg_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(9) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_AUD] = {
> > +		.num_clks = ARRAY_SIZE(ape_slcg_clkids),
> > +		.clk_init_data = ape_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_ape_mbist_war,
> > +	},
> > +	[TEGRA_POWERGATE_VE2] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRD,
> > +		.lvl2_mask = BIT(22),
> > +	},
> > +};
> > +
> > +void tegra210_clk_handle_mbist_war(unsigned int id)
> > +{
> > +	int err;
> > +	struct tegra210_domain_mbist_war *mbist_war;
> > +
> > +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
> > +		WARN(1, "unknown domain id in MBIST WAR handler\n");
> > +		return;
> > +	}
> > +
> > +	mbist_war = &tegra210_pg_mbist_war[id];
> > +	if (!mbist_war->handle_lvl2_ovr)
> > +		return;
> > +
> > +	err = mbist_war->handle_lvl2_ovr(mbist_war);
> 
> Why not move the clk_bulk_prepare_enable/disable_unprepare and
> mutex_lock/unlock functions into this function around the call to
> ->handle_lvl2_ovr to save the duplication of that code in each of the
> war functions?
> 

This could be done yes.

> > +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
> > +}
> 
> I think that the above function should return an error and we should let
> the power-domain power-on fail.
> 

This would only be useful if the user (tegra_powergate_power_up) would do
rollback. I don't think that's done correctly today.

> > +
> > +
> >  void tegra210_put_utmipll_in_iddq(void)
> >  {
> >  	u32 reg;
> > @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
> >  	return 0;
> >  }
> >  
> > +static void tegra210_mbist_clk_init(void)
> > +{
> > +	int i, j;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
> > +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
> > +		struct clk_bulk_data *clk_data;
> > +
> > +		if (!num_clks)
> > +			continue;
> > +
> > +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
> > +					 GFP_KERNEL);
> > +		if (WARN(!clk_data,
> > +			"no space for MBIST WAR clk array for %d\n", i)) {
> > +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
> > +			continue;
> > +		}
> 
> Printing error messages on memory allocation failures are not needed and
> have been removed from various drivers. So lets no add any error
> messages or warnings here.
> 
> Also I think that we should just return an error here and not bother
> continuing as there is no point.
> 
> > +
> > +		tegra210_pg_mbist_war[i].clks = clk_data;
> 
> I think that you should only populate this when all the clocks have been
> initialised correctly. You could then use this to check the clocks have
> been setup correctly when executing the war.
> 

For some domains no extra clocks are needed (ie the clocks enabled by the
power domain driver are enough). So an extra flag would be needed then.

> > +		for (j = 0; j < num_clks; j++) {
> > +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
> > +			struct clk *clk = clks[clk_id];
> > +
> > +			if (IS_ERR(clk)) {
> > +				clk_data[j].clk = NULL;
> > +				WARN(1, "clk_id: %d\n", clk_id);
> 
> I think that we should return an error here.
> 

I don't think letting clock init fail because of this, is a good idea. Too
many things rely on working clocks.

> > +			} else {
> > +				clk_data[j].clk = clk;
> > +			}
> > +		}
> > +	}
> > +}
> > +
> >  /**
> >   * tegra210_clock_init - Tegra210-specific clock initialization
> >   * @np: struct device_node * of the DT node for the SoC CAR IP block
> > @@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
> >  		return;
> >  	}
> >  
> > +	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
> > +	if (!ape_base) {
> > +		pr_err("ioremap tegra210 APE failed\n");
> > +		return;
> > +	}
> > +
> > +	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
> > +	if (!dispa_base) {
> > +		pr_err("ioremap tegra210 DISPA failed\n");
> > +		return;
> > +	}
> > +
> > +	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
> > +	if (!vic_base) {
> > +		pr_err("ioremap tegra210 VIC failed\n");
> > +		return;
> > +	}
> > +
> >  	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
> >  			      TEGRA210_CAR_BANK_COUNT);
> >  	if (!clks)
> > @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
> >  	tegra_add_of_provider(np);
> >  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
> >  
> > +	tegra210_mbist_clk_init();
> > +
> 
> Maybe add a print here if the mbist init fails and return. I understand
> it may not be a critical failure but it should never fail.
> 

You mean have the entire clock init fail and undo all the clock registrations?
That seems overkill to me. Returning early would only prevent some sleep states
from working because tegra_cpu_car_ops will not be initialized then. So I would
do a warning then.

> >  	tegra_cpu_car_ops = &tegra210_cpu_car_ops;
> >  }
> >  CLK_OF_DECLARE(tegra210, "nvidia,tegra210-car", tegra210_clock_init);
> > diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
> > index d23c9cf..a3d46f7 100644
> > --- a/include/linux/clk/tegra.h
> > +++ b/include/linux/clk/tegra.h
> > @@ -128,5 +128,10 @@ static inline void tegra_cpu_clock_resume(void)
> >  extern void tegra210_set_sata_pll_seq_sw(bool state);
> >  extern void tegra210_put_utmipll_in_iddq(void);
> >  extern void tegra210_put_utmipll_out_iddq(void);
> > +#ifndef CONFIG_ARCH_TEGRA_210_SOC
> > +static inline void tegra210_clk_handle_mbist_war(unsigned int id) {}
> > +#else
> > +extern void tegra210_clk_handle_mbist_war(unsigned int id);
> > +#endif
> >  
> >  #endif /* __LINUX_CLK_TEGRA_H_ */
> 
> Cheers
> Jon
> 
> -- 
> nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Peter De Schrijver]

On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:
> 
> On 23/01/18 09:22, Peter De Schrijver wrote:
> > Tegra210 has a hw bug which can cause IP blocks to lock up when ungating a
> > domain. The reason is that the logic responsible for resetting the memory
> > built-in self test mode can come up in an undefined state because its
> > clock is gated by a second level clock gate (SLCG). Work around this by
> > making sure the logic will get some clock edges by ensuring the relevant
> > clock is enabled and temporarily override the relevant SLCGs.
> > Unfortunately for some IP blocks, the control bits for overriding the
> > SLCGs are not in CAR, but in the IP block itself. This means we need to
> > map a few extra register banks in the clock code.
> > 
> > Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> > ---
> >  drivers/clk/tegra/clk-tegra210.c | 395 ++++++++++++++++++++++++++++++++++++++-
> >  include/linux/clk/tegra.h        |   5 +
> >  2 files changed, 398 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/clk/tegra/clk-tegra210.c b/drivers/clk/tegra/clk-tegra210.c
> > index f790c2d..f61ec1f 100644
> > --- a/drivers/clk/tegra/clk-tegra210.c
> > +++ b/drivers/clk/tegra/clk-tegra210.c
> > @@ -22,10 +22,12 @@
> >  #include <linux/of_address.h>
> >  #include <linux/delay.h>
> >  #include <linux/export.h>
> > +#include <linux/mutex.h>
> >  #include <linux/clk/tegra.h>
> >  #include <dt-bindings/clock/tegra210-car.h>
> >  #include <dt-bindings/reset/tegra210-car.h>
> >  #include <linux/iopoll.h>
> > +#include <soc/tegra/pmc.h>
> >  
> >  #include "clk.h"
> >  #include "clk-id.h"
> > @@ -232,6 +234,30 @@
> >  #define CLK_RST_CONTROLLER_RST_DEV_Y_SET 0x2a8
> >  #define CLK_RST_CONTROLLER_RST_DEV_Y_CLR 0x2ac
> >  
> > +#define LVL2_CLK_GATE_OVRA 0xf8
> > +#define LVL2_CLK_GATE_OVRC 0x3a0
> > +#define LVL2_CLK_GATE_OVRD 0x3a4
> > +#define LVL2_CLK_GATE_OVRE 0x554
> > +
> > +/* I2S registers to handle during APE MBIST WAR */
> > +#define TEGRA210_I2S_BASE  0x11000
> > +#define TEGRA210_I2S_SIZE  0x100
> > +#define TEGRA210_I2S_CTRLS 5
> > +#define TEGRA210_I2S_CG    0x88
> > +#define TEGRA210_I2S_CTRL  0xa0
> > +
> > +/* DISPA registers to handle during MBIST WAR */
> > +#define DC_CMD_DISPLAY_COMMAND 0xc8
> > +#define DC_COM_DSC_TOP_CTL 0xcf8
> > +
> > +/* VIC register to handle during MBIST WAR */
> > +#define NV_PVIC_THI_SLCG_OVERRIDE_LOW 0x8c
> > +
> > +/* APE, DISPA and VIC base addesses needed for MBIST WAR */
> > +#define TEGRA210_APE_BASE  0x702c0000
> 
> Nit-pick, I think that it is only necessary to map the AHUB here as the
> I2S are a sub-device of this. So we only need to map 0x702d0000-0x702dffff.
> 
> > +#define TEGRA210_DISPA_BASE 0x54200000
> > +#define TEGRA210_VIC_BASE  0x54340000
> > +
> >  /*
> >   * SDM fractional divisor is 16-bit 2's complement signed number within
> >   * (-2^12 ... 2^12-1) range. Represented in PLL data structure as unsigned
> > @@ -256,8 +282,22 @@
> >  } tegra210_cpu_clk_sctx;
> >  #endif
> >  
> > +struct tegra210_domain_mbist_war {
> > +	int (*handle_lvl2_ovr)(struct tegra210_domain_mbist_war *mbist);
> > +	const u32 lvl2_offset;
> > +	const u32 lvl2_mask;
> > +	const unsigned int num_clks;
> > +	const unsigned int *clk_init_data;
> > +	struct clk_bulk_data *clks;
> > +};
> > +
> > +static struct clk **clks;
> > +
> >  static void __iomem *clk_base;
> >  static void __iomem *pmc_base;
> > +static void __iomem *ape_base;
> > +static void __iomem *dispa_base;
> > +static void __iomem *vic_base;
> >  
> >  static unsigned long osc_freq;
> >  static unsigned long pll_ref_freq;
> > @@ -268,6 +308,7 @@
> >  static DEFINE_SPINLOCK(pll_u_lock);
> >  static DEFINE_SPINLOCK(sor1_lock);
> >  static DEFINE_SPINLOCK(emc_lock);
> > +static DEFINE_MUTEX(lvl2_ovr_lock);
> >  
> >  /* possible OSC frequencies in Hz */
> >  static unsigned long tegra210_input_freq[] = {
> > @@ -311,6 +352,8 @@
> >  #define PLLA_MISC2_WRITE_MASK		0x06ffffff
> >  
> >  /* PLLD */
> > +#define PLLD_BASE_CSI_CLKSOURCE		(1 << 23)
> > +
> >  #define PLLD_MISC0_EN_SDM		(1 << 16)
> >  #define PLLD_MISC0_LOCK_OVERRIDE	(1 << 17)
> >  #define PLLD_MISC0_LOCK_ENABLE		(1 << 18)
> > @@ -514,6 +557,176 @@ void tegra210_set_sata_pll_seq_sw(bool state)
> >  }
> >  EXPORT_SYMBOL_GPL(tegra210_set_sata_pll_seq_sw);
> >  
> > +static int tegra210_generic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 val;
> > +	int err;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	val = readl_relaxed(clk_base + mbist->lvl2_offset);
> > +	writel_relaxed(val | mbist->lvl2_mask, clk_base + mbist->lvl2_offset);
> > +	fence_udelay(1, clk_base);
> > +	writel_relaxed(val, clk_base + mbist->lvl2_offset);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_venc_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 csi_src, ovra, ovre;
> > +	int err;
> > +	unsigned long flags = 0;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +	spin_lock_irqsave(&pll_d_lock, flags);
> 
> Downstream does not appear to implement a spinlock around this code
> AFAICT. With the delays it seems we are disabling interrupts for quite a
> bit of time. If there is no other way to get around this then fine, but
> I am curious if we need this? Are you worrying about the PLLD being
> updated at the same time this is happening? Is that likely see that

Yes. We have to be sure the CSI source is not reset to 'brick'. That would
be the clock recovered from the CSI input signal, which is likely to be
missing. So effectively there would be no clock pulses then.

> devices using the PLLD will be waiting for the powerdomain to be enabled
> first?
> 

Hopefully not, but if they would, the resulting random hangs of the IP block
wouldn't be easy to trace back to accidental changes of the CSI source during
this WAR procedure.

> > +
> > +	csi_src = readl_relaxed(clk_base + PLLD_BASE);
> > +	writel_relaxed(csi_src | PLLD_BASE_CSI_CLKSOURCE, clk_base + PLLD_BASE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> > +	writel_relaxed(ovra | BIT(15), clk_base + LVL2_CLK_GATE_OVRA);
> > +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(ovre | BIT(3), clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> > +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(csi_src, clk_base + PLLD_BASE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	spin_unlock_irqrestore(&pll_d_lock, flags);
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_disp_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 ovra, dsc_top_ctrl;
> > +	int err;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	ovra = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRA);
> > +	writel_relaxed(ovra | BIT(1), clk_base + LVL2_CLK_GATE_OVRA);
> > +	fence_udelay(1, clk_base);
> > +
> > +	dsc_top_ctrl = readl_relaxed(dispa_base + DC_COM_DSC_TOP_CTL);
> > +	writel_relaxed(dsc_top_ctrl | BIT(2), dispa_base + DC_COM_DSC_TOP_CTL);
> > +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> > +	writel_relaxed(dsc_top_ctrl, dispa_base + DC_COM_DSC_TOP_CTL);
> > +	readl_relaxed(dispa_base + DC_CMD_DISPLAY_COMMAND);
> > +
> > +	writel_relaxed(ovra, clk_base + LVL2_CLK_GATE_OVRA);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_vic_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	u32 ovre, val;
> > +	int err;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(ovre | BIT(5), clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	val = readl_relaxed(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +	writel_relaxed(val | BIT(0) | GENMASK(7, 2) | BIT(24),
> > +			vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +	fence_udelay(1, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +
> > +	writel_relaxed(val, vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +	readl(vic_base + NV_PVIC_THI_SLCG_OVERRIDE_LOW);
> > +
> > +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> > +static int tegra210_ape_mbist_war(struct tegra210_domain_mbist_war *mbist)
> > +{
> > +	int err, i;
> > +	u32 ovrc, ovre;
> > +	void __iomem *i2s_base;
> > +
> > +	err = clk_bulk_prepare_enable(mbist->num_clks, mbist->clks);
> > +	if (err < 0)
> > +		return err;
> > +
> > +	mutex_lock(&lvl2_ovr_lock);
> > +
> > +	ovrc = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRC);
> > +	ovre = readl_relaxed(clk_base + LVL2_CLK_GATE_OVRE);
> > +	writel_relaxed(ovrc | BIT(1), clk_base + LVL2_CLK_GATE_OVRC);
> > +	writel_relaxed(ovre | BIT(10) | BIT(11),
> > +			clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	i2s_base = ape_base + TEGRA210_I2S_BASE;
> > +	for (i = 0; i < TEGRA210_I2S_CTRLS; i++) {
> > +		u32 i2s_ctrl;
> > +
> > +		i2s_ctrl = readl_relaxed(i2s_base + TEGRA210_I2S_CTRL);
> > +		writel_relaxed(i2s_ctrl | BIT(10),
> > +				i2s_base + TEGRA210_I2S_CTRL);
> > +		writel_relaxed(0, i2s_base + TEGRA210_I2S_CG);
> > +		readl(i2s_base + TEGRA210_I2S_CG);
> > +		writel_relaxed(1, i2s_base + TEGRA210_I2S_CG);
> > +		writel_relaxed(i2s_ctrl, i2s_base + TEGRA210_I2S_CTRL);
> > +		readl(i2s_base + TEGRA210_I2S_CTRL);
> > +
> > +		i2s_base += TEGRA210_I2S_SIZE;
> > +	}
> > +
> > +	writel_relaxed(ovrc, clk_base + LVL2_CLK_GATE_OVRC);
> > +	writel_relaxed(ovre, clk_base + LVL2_CLK_GATE_OVRE);
> > +	fence_udelay(1, clk_base);
> > +
> > +	mutex_unlock(&lvl2_ovr_lock);
> > +
> > +	clk_bulk_disable_unprepare(mbist->num_clks, mbist->clks);
> > +
> > +	return 0;
> > +}
> > +
> >  static inline void _pll_misc_chk_default(void __iomem *base,
> >  					struct tegra_clk_pll_params *params,
> >  					u8 misc_num, u32 default_val, u32 mask)
> > @@ -2412,13 +2625,137 @@ struct utmi_clk_param {
> >  	{ "pll_a1", &pll_a1_params, tegra_clk_pll_a1, "pll_ref" },
> >  };
> >  
> > -static struct clk **clks;
> > -
> >  static const char * const aclk_parents[] = {
> >  	"pll_a1", "pll_c", "pll_p", "pll_a_out0", "pll_c2", "pll_c3",
> >  	"clk_m"
> >  };
> >  
> > +static const unsigned int nvjpg_slcg_clkids[] = { TEGRA210_CLK_NVDEC };
> > +static const unsigned int nvdec_slcg_clkids[] = { TEGRA210_CLK_NVJPG };
> > +static const unsigned int sor_slcg_clkids[] = { TEGRA210_CLK_HDA2CODEC_2X,
> > +	TEGRA210_CLK_HDA2HDMI, TEGRA210_CLK_DISP1, TEGRA210_CLK_DISP2 };
> > +static const unsigned int disp_slcg_clkids[] = { TEGRA210_CLK_LA,
> > +	TEGRA210_CLK_HOST1X};
> > +static const unsigned int xusba_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> > +	TEGRA210_CLK_XUSB_DEV };
> > +static const unsigned int xusbb_slcg_clkids[] = { TEGRA210_CLK_XUSB_HOST,
> > +	TEGRA210_CLK_XUSB_SS };
> > +static const unsigned int xusbc_slcg_clkids[] = { TEGRA210_CLK_XUSB_DEV,
> > +	TEGRA210_CLK_XUSB_SS };
> > +static const unsigned int venc_slcg_clkids[] = { TEGRA210_CLK_HOST1X,
> > +	TEGRA210_CLK_PLL_D };
> > +static const unsigned int ape_slcg_clkids[] = { TEGRA210_CLK_ACLK,
> > +	TEGRA210_CLK_I2S0, TEGRA210_CLK_I2S1, TEGRA210_CLK_I2S2,
> > +	TEGRA210_CLK_I2S3, TEGRA210_CLK_I2S4, TEGRA210_CLK_SPDIF_OUT,
> > +	TEGRA210_CLK_D_AUDIO };
> > +static const unsigned int vic_slcg_clkids[] = { TEGRA210_CLK_HOST1X };
> > +
> > +static struct tegra210_domain_mbist_war tegra210_pg_mbist_war[] = {
> > +	[TEGRA_POWERGATE_VENC] = {
> > +		.handle_lvl2_ovr = tegra210_venc_mbist_war,
> > +		.num_clks = ARRAY_SIZE(venc_slcg_clkids),
> > +		.clk_init_data = venc_slcg_clkids,
> > +	},
> > +	[TEGRA_POWERGATE_SATA] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(0) | BIT(17) | BIT(19),
> > +	},
> > +	[TEGRA_POWERGATE_MPE] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRE,
> > +		.lvl2_mask = BIT(2),
> > +	},
> > +	[TEGRA_POWERGATE_SOR] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.num_clks = ARRAY_SIZE(sor_slcg_clkids),
> > +		.clk_init_data = sor_slcg_clkids,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> > +		.lvl2_mask = BIT(1) | BIT(2),
> > +	},
> > +	[TEGRA_POWERGATE_DIS] = {
> > +		.handle_lvl2_ovr = tegra210_disp_mbist_war,
> > +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> > +		.clk_init_data = disp_slcg_clkids,
> > +	},
> > +	[TEGRA_POWERGATE_DISB] = {
> > +		.num_clks = ARRAY_SIZE(disp_slcg_clkids),
> > +		.clk_init_data = disp_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRA,
> > +		.lvl2_mask = BIT(2),
> > +	},
> > +	[TEGRA_POWERGATE_XUSBA] = {
> > +		.num_clks = ARRAY_SIZE(xusba_slcg_clkids),
> > +		.clk_init_data = xusba_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(30) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_XUSBB] = {
> > +		.num_clks = ARRAY_SIZE(xusbb_slcg_clkids),
> > +		.clk_init_data = xusbb_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(30) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_XUSBC] = {
> > +		.num_clks = ARRAY_SIZE(xusbc_slcg_clkids),
> > +		.clk_init_data = xusbc_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(30) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_VIC] = {
> > +		.num_clks = ARRAY_SIZE(vic_slcg_clkids),
> > +		.clk_init_data = vic_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_vic_mbist_war,
> > +	},
> > +	[TEGRA_POWERGATE_NVDEC] = {
> > +		.num_clks = ARRAY_SIZE(nvdec_slcg_clkids),
> > +		.clk_init_data = nvdec_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(9) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_NVJPG] = {
> > +		.num_clks = ARRAY_SIZE(nvjpg_slcg_clkids),
> > +		.clk_init_data = nvjpg_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRC,
> > +		.lvl2_mask = BIT(9) | BIT(31),
> > +	},
> > +	[TEGRA_POWERGATE_AUD] = {
> > +		.num_clks = ARRAY_SIZE(ape_slcg_clkids),
> > +		.clk_init_data = ape_slcg_clkids,
> > +		.handle_lvl2_ovr = tegra210_ape_mbist_war,
> > +	},
> > +	[TEGRA_POWERGATE_VE2] = {
> > +		.handle_lvl2_ovr = tegra210_generic_mbist_war,
> > +		.lvl2_offset = LVL2_CLK_GATE_OVRD,
> > +		.lvl2_mask = BIT(22),
> > +	},
> > +};
> > +
> > +void tegra210_clk_handle_mbist_war(unsigned int id)
> > +{
> > +	int err;
> > +	struct tegra210_domain_mbist_war *mbist_war;
> > +
> > +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
> > +		WARN(1, "unknown domain id in MBIST WAR handler\n");
> > +		return;
> > +	}
> > +
> > +	mbist_war = &tegra210_pg_mbist_war[id];
> > +	if (!mbist_war->handle_lvl2_ovr)
> > +		return;
> > +
> > +	err = mbist_war->handle_lvl2_ovr(mbist_war);
> 
> Why not move the clk_bulk_prepare_enable/disable_unprepare and
> mutex_lock/unlock functions into this function around the call to
> ->handle_lvl2_ovr to save the duplication of that code in each of the
> war functions?
> 

This could be done yes.

> > +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
> > +}
> 
> I think that the above function should return an error and we should let
> the power-domain power-on fail.
> 

This would only be useful if the user (tegra_powergate_power_up) would do
rollback. I don't think that's done correctly today.

> > +
> > +
> >  void tegra210_put_utmipll_in_iddq(void)
> >  {
> >  	u32 reg;
> > @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
> >  	return 0;
> >  }
> >  
> > +static void tegra210_mbist_clk_init(void)
> > +{
> > +	int i, j;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
> > +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
> > +		struct clk_bulk_data *clk_data;
> > +
> > +		if (!num_clks)
> > +			continue;
> > +
> > +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
> > +					 GFP_KERNEL);
> > +		if (WARN(!clk_data,
> > +			"no space for MBIST WAR clk array for %d\n", i)) {
> > +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
> > +			continue;
> > +		}
> 
> Printing error messages on memory allocation failures are not needed and
> have been removed from various drivers. So lets no add any error
> messages or warnings here.
> 
> Also I think that we should just return an error here and not bother
> continuing as there is no point.
> 
> > +
> > +		tegra210_pg_mbist_war[i].clks = clk_data;
> 
> I think that you should only populate this when all the clocks have been
> initialised correctly. You could then use this to check the clocks have
> been setup correctly when executing the war.
> 

For some domains no extra clocks are needed (ie the clocks enabled by the
power domain driver are enough). So an extra flag would be needed then.

> > +		for (j = 0; j < num_clks; j++) {
> > +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
> > +			struct clk *clk = clks[clk_id];
> > +
> > +			if (IS_ERR(clk)) {
> > +				clk_data[j].clk = NULL;
> > +				WARN(1, "clk_id: %d\n", clk_id);
> 
> I think that we should return an error here.
> 

I don't think letting clock init fail because of this, is a good idea. Too
many things rely on working clocks.

> > +			} else {
> > +				clk_data[j].clk = clk;
> > +			}
> > +		}
> > +	}
> > +}
> > +
> >  /**
> >   * tegra210_clock_init - Tegra210-specific clock initialization
> >   * @np: struct device_node * of the DT node for the SoC CAR IP block
> > @@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
> >  		return;
> >  	}
> >  
> > +	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
> > +	if (!ape_base) {
> > +		pr_err("ioremap tegra210 APE failed\n");
> > +		return;
> > +	}
> > +
> > +	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
> > +	if (!dispa_base) {
> > +		pr_err("ioremap tegra210 DISPA failed\n");
> > +		return;
> > +	}
> > +
> > +	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
> > +	if (!vic_base) {
> > +		pr_err("ioremap tegra210 VIC failed\n");
> > +		return;
> > +	}
> > +
> >  	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
> >  			      TEGRA210_CAR_BANK_COUNT);
> >  	if (!clks)
> > @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
> >  	tegra_add_of_provider(np);
> >  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
> >  
> > +	tegra210_mbist_clk_init();
> > +
> 
> Maybe add a print here if the mbist init fails and return. I understand
> it may not be a critical failure but it should never fail.
> 

You mean have the entire clock init fail and undo all the clock registrations?
That seems overkill to me. Returning early would only prevent some sleep states
from working because tegra_cpu_car_ops will not be initialized then. So I would
do a warning then.

> >  	tegra_cpu_car_ops = &tegra210_cpu_car_ops;
> >  }
> >  CLK_OF_DECLARE(tegra210, "nvidia,tegra210-car", tegra210_clock_init);
> > diff --git a/include/linux/clk/tegra.h b/include/linux/clk/tegra.h
> > index d23c9cf..a3d46f7 100644
> > --- a/include/linux/clk/tegra.h
> > +++ b/include/linux/clk/tegra.h
> > @@ -128,5 +128,10 @@ static inline void tegra_cpu_clock_resume(void)
> >  extern void tegra210_set_sata_pll_seq_sw(bool state);
> >  extern void tegra210_put_utmipll_in_iddq(void);
> >  extern void tegra210_put_utmipll_out_iddq(void);
> > +#ifndef CONFIG_ARCH_TEGRA_210_SOC
> > +static inline void tegra210_clk_handle_mbist_war(unsigned int id) {}
> > +#else
> > +extern void tegra210_clk_handle_mbist_war(unsigned int id);
> > +#endif
> >  
> >  #endif /* __LINUX_CLK_TEGRA_H_ */
> 
> Cheers
> Jon
> 
> -- 
> nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Jon Hunter]

On 25/01/18 09:02, Peter De Schrijver wrote:
> On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:

...

>>> +void tegra210_clk_handle_mbist_war(unsigned int id)
>>> +{
>>> +	int err;
>>> +	struct tegra210_domain_mbist_war *mbist_war;
>>> +
>>> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
>>> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
>>> +		return;
>>> +	}
>>> +
>>> +	mbist_war = &tegra210_pg_mbist_war[id];
>>> +	if (!mbist_war->handle_lvl2_ovr)
>>> +		return;
>>> +
>>> +	err = mbist_war->handle_lvl2_ovr(mbist_war);
>>
>> Why not move the clk_bulk_prepare_enable/disable_unprepare and
>> mutex_lock/unlock functions into this function around the call to
>> ->handle_lvl2_ovr to save the duplication of that code in each of the
>> war functions?
>>
> 
> This could be done yes.
> 
>>> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
>>> +}
>>
>> I think that the above function should return an error and we should let
>> the power-domain power-on fail.
>>
> 
> This would only be useful if the user (tegra_powergate_power_up) would do
> rollback. I don't think that's done correctly today.

It does and so I think that we should return an error.

>>> +
>>> +
>>>  void tegra210_put_utmipll_in_iddq(void)
>>>  {
>>>  	u32 reg;
>>> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
>>>  	return 0;
>>>  }
>>>  
>>> +static void tegra210_mbist_clk_init(void)
>>> +{
>>> +	int i, j;
>>> +
>>> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
>>> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
>>> +		struct clk_bulk_data *clk_data;
>>> +
>>> +		if (!num_clks)
>>> +			continue;
>>> +
>>> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
>>> +					 GFP_KERNEL);
>>> +		if (WARN(!clk_data,
>>> +			"no space for MBIST WAR clk array for %d\n", i)) {
>>> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
>>> +			continue;
>>> +		}
>>
>> Printing error messages on memory allocation failures are not needed and
>> have been removed from various drivers. So lets no add any error
>> messages or warnings here.
>>
>> Also I think that we should just return an error here and not bother
>> continuing as there is no point.

So maybe here just ...

		if (WARN_ON(!clk_data))
			return -ENOMEM;

>>> +
>>> +		tegra210_pg_mbist_war[i].clks = clk_data;
>>
>> I think that you should only populate this when all the clocks have been
>> initialised correctly. You could then use this to check the clocks have
>> been setup correctly when executing the war.
>>
> 
> For some domains no extra clocks are needed (ie the clocks enabled by the
> power domain driver are enough). So an extra flag would be needed then.

Yes but you have num_clks to detect if a domain has extra clocks. So you
can use both of these to detect if the clocks are setup correctly. Right?

>>> +		for (j = 0; j < num_clks; j++) {
>>> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
>>> +			struct clk *clk = clks[clk_id];
>>> +
>>> +			if (IS_ERR(clk)) {
>>> +				clk_data[j].clk = NULL;
>>> +				WARN(1, "clk_id: %d\n", clk_id);
>>
>> I think that we should return an error here.
>>
> 
> I don't think letting clock init fail because of this, is a good idea. Too
> many things rely on working clocks.

It should never fail and if it does something is badly broken.

Maybe what we could do ...

			if (WARN_ON(IS_ERR(clk))) {
				tegra210_pg_mbist_war[i].clks = NULL;
				break;
			}

			clk_data[j].clk = clk;

Then we can check in tegra210_clk_handle_mbist_war() ...

	if (mbist_war->num_clks && !mbist_war.clks)
		return -ENODEV;

Does that work?

>>> +			} else {
>>> +				clk_data[j].clk = clk;
>>> +			}
>>> +		}
>>> +	}
>>> +}
>>> +
>>>  /**
>>>   * tegra210_clock_init - Tegra210-specific clock initialization
>>>   * @np: struct device_node * of the DT node for the SoC CAR IP block
>>> @@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
>>>  		return;
>>>  	}
>>>  
>>> +	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
>>> +	if (!ape_base) {
>>> +		pr_err("ioremap tegra210 APE failed\n");
>>> +		return;
>>> +	}
>>> +
>>> +	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
>>> +	if (!dispa_base) {
>>> +		pr_err("ioremap tegra210 DISPA failed\n");
>>> +		return;
>>> +	}
>>> +
>>> +	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
>>> +	if (!vic_base) {
>>> +		pr_err("ioremap tegra210 VIC failed\n");
>>> +		return;
>>> +	}
>>> +
>>>  	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
>>>  			      TEGRA210_CAR_BANK_COUNT);
>>>  	if (!clks)
>>> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
>>>  	tegra_add_of_provider(np);
>>>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
>>>  
>>> +	tegra210_mbist_clk_init();
>>> +
>>
>> Maybe add a print here if the mbist init fails and return. I understand
>> it may not be a critical failure but it should never fail.
>>
> 
> You mean have the entire clock init fail and undo all the clock registrations?
> That seems overkill to me. Returning early would only prevent some sleep states
> from working because tegra_cpu_car_ops will not be initialized then. So I would
> do a warning then.

I don't think it is necessary to undo it. Ok, don't worry about
returning an error here, the warnings should be sufficient.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Jon Hunter]

On 25/01/18 09:02, Peter De Schrijver wrote:
> On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:

...

>>> +void tegra210_clk_handle_mbist_war(unsigned int id)
>>> +{
>>> +	int err;
>>> +	struct tegra210_domain_mbist_war *mbist_war;
>>> +
>>> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
>>> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
>>> +		return;
>>> +	}
>>> +
>>> +	mbist_war = &tegra210_pg_mbist_war[id];
>>> +	if (!mbist_war->handle_lvl2_ovr)
>>> +		return;
>>> +
>>> +	err = mbist_war->handle_lvl2_ovr(mbist_war);
>>
>> Why not move the clk_bulk_prepare_enable/disable_unprepare and
>> mutex_lock/unlock functions into this function around the call to
>> ->handle_lvl2_ovr to save the duplication of that code in each of the
>> war functions?
>>
> 
> This could be done yes.
> 
>>> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
>>> +}
>>
>> I think that the above function should return an error and we should let
>> the power-domain power-on fail.
>>
> 
> This would only be useful if the user (tegra_powergate_power_up) would do
> rollback. I don't think that's done correctly today.

It does and so I think that we should return an error.

>>> +
>>> +
>>>  void tegra210_put_utmipll_in_iddq(void)
>>>  {
>>>  	u32 reg;
>>> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
>>>  	return 0;
>>>  }
>>>  
>>> +static void tegra210_mbist_clk_init(void)
>>> +{
>>> +	int i, j;
>>> +
>>> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
>>> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
>>> +		struct clk_bulk_data *clk_data;
>>> +
>>> +		if (!num_clks)
>>> +			continue;
>>> +
>>> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
>>> +					 GFP_KERNEL);
>>> +		if (WARN(!clk_data,
>>> +			"no space for MBIST WAR clk array for %d\n", i)) {
>>> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
>>> +			continue;
>>> +		}
>>
>> Printing error messages on memory allocation failures are not needed and
>> have been removed from various drivers. So lets no add any error
>> messages or warnings here.
>>
>> Also I think that we should just return an error here and not bother
>> continuing as there is no point.

So maybe here just ...

		if (WARN_ON(!clk_data))
			return -ENOMEM;

>>> +
>>> +		tegra210_pg_mbist_war[i].clks = clk_data;
>>
>> I think that you should only populate this when all the clocks have been
>> initialised correctly. You could then use this to check the clocks have
>> been setup correctly when executing the war.
>>
> 
> For some domains no extra clocks are needed (ie the clocks enabled by the
> power domain driver are enough). So an extra flag would be needed then.

Yes but you have num_clks to detect if a domain has extra clocks. So you
can use both of these to detect if the clocks are setup correctly. Right?

>>> +		for (j = 0; j < num_clks; j++) {
>>> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
>>> +			struct clk *clk = clks[clk_id];
>>> +
>>> +			if (IS_ERR(clk)) {
>>> +				clk_data[j].clk = NULL;
>>> +				WARN(1, "clk_id: %d\n", clk_id);
>>
>> I think that we should return an error here.
>>
> 
> I don't think letting clock init fail because of this, is a good idea. Too
> many things rely on working clocks.

It should never fail and if it does something is badly broken.

Maybe what we could do ...

			if (WARN_ON(IS_ERR(clk))) {
				tegra210_pg_mbist_war[i].clks = NULL;
				break;
			}

			clk_data[j].clk = clk;

Then we can check in tegra210_clk_handle_mbist_war() ...

	if (mbist_war->num_clks && !mbist_war.clks)
		return -ENODEV;

Does that work?

>>> +			} else {
>>> +				clk_data[j].clk = clk;
>>> +			}
>>> +		}
>>> +	}
>>> +}
>>> +
>>>  /**
>>>   * tegra210_clock_init - Tegra210-specific clock initialization
>>>   * @np: struct device_node * of the DT node for the SoC CAR IP block
>>> @@ -3197,6 +3568,24 @@ static void __init tegra210_clock_init(struct device_node *np)
>>>  		return;
>>>  	}
>>>  
>>> +	ape_base = ioremap(TEGRA210_APE_BASE, 256*1024);
>>> +	if (!ape_base) {
>>> +		pr_err("ioremap tegra210 APE failed\n");
>>> +		return;
>>> +	}
>>> +
>>> +	dispa_base = ioremap(TEGRA210_DISPA_BASE, 256*1024);
>>> +	if (!dispa_base) {
>>> +		pr_err("ioremap tegra210 DISPA failed\n");
>>> +		return;
>>> +	}
>>> +
>>> +	vic_base = ioremap(TEGRA210_VIC_BASE, 256*1024);
>>> +	if (!vic_base) {
>>> +		pr_err("ioremap tegra210 VIC failed\n");
>>> +		return;
>>> +	}
>>> +
>>>  	clks = tegra_clk_init(clk_base, TEGRA210_CLK_CLK_MAX,
>>>  			      TEGRA210_CAR_BANK_COUNT);
>>>  	if (!clks)
>>> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
>>>  	tegra_add_of_provider(np);
>>>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
>>>  
>>> +	tegra210_mbist_clk_init();
>>> +
>>
>> Maybe add a print here if the mbist init fails and return. I understand
>> it may not be a critical failure but it should never fail.
>>
> 
> You mean have the entire clock init fail and undo all the clock registrations?
> That seems overkill to me. Returning early would only prevent some sleep states
> from working because tegra_cpu_car_ops will not be initialized then. So I would
> do a warning then.

I don't think it is necessary to undo it. Ok, don't worry about
returning an error here, the warnings should be sufficient.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Peter De Schrijver]

On Thu, Jan 25, 2018 at 10:19:08AM +0000, Jon Hunter wrote:
> 
> On 25/01/18 09:02, Peter De Schrijver wrote:
> > On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:
> 
> ...
> 
> >>> +void tegra210_clk_handle_mbist_war(unsigned int id)
> >>> +{
> >>> +	int err;
> >>> +	struct tegra210_domain_mbist_war *mbist_war;
> >>> +
> >>> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
> >>> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
> >>> +		return;
> >>> +	}
> >>> +
> >>> +	mbist_war = &tegra210_pg_mbist_war[id];
> >>> +	if (!mbist_war->handle_lvl2_ovr)
> >>> +		return;
> >>> +
> >>> +	err = mbist_war->handle_lvl2_ovr(mbist_war);
> >>
> >> Why not move the clk_bulk_prepare_enable/disable_unprepare and
> >> mutex_lock/unlock functions into this function around the call to
> >> ->handle_lvl2_ovr to save the duplication of that code in each of the
> >> war functions?
> >>
> > 
> > This could be done yes.
> > 
> >>> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
> >>> +}
> >>
> >> I think that the above function should return an error and we should let
> >> the power-domain power-on fail.
> >>
> > 
> > This would only be useful if the user (tegra_powergate_power_up) would do
> > rollback. I don't think that's done correctly today.
> 
> It does and so I think that we should return an error.
> 

Ok.

> >>> +
> >>> +
> >>>  void tegra210_put_utmipll_in_iddq(void)
> >>>  {
> >>>  	u32 reg;
> >>> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
> >>>  	return 0;
> >>>  }
> >>>  
> >>> +static void tegra210_mbist_clk_init(void)
> >>> +{
> >>> +	int i, j;
> >>> +
> >>> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
> >>> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
> >>> +		struct clk_bulk_data *clk_data;
> >>> +
> >>> +		if (!num_clks)
> >>> +			continue;
> >>> +
> >>> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
> >>> +					 GFP_KERNEL);
> >>> +		if (WARN(!clk_data,
> >>> +			"no space for MBIST WAR clk array for %d\n", i)) {
> >>> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
> >>> +			continue;
> >>> +		}
> >>
> >> Printing error messages on memory allocation failures are not needed and
> >> have been removed from various drivers. So lets no add any error
> >> messages or warnings here.
> >>
> >> Also I think that we should just return an error here and not bother
> >> continuing as there is no point.
> 
> So maybe here just ...
> 
> 		if (WARN_ON(!clk_data))
> 			return -ENOMEM;
> 

Given that we do WARN_ON() here..

> >>> +
> >>> +		tegra210_pg_mbist_war[i].clks = clk_data;
> >>
> >> I think that you should only populate this when all the clocks have been
> >> initialised correctly. You could then use this to check the clocks have
> >> been setup correctly when executing the war.
> >>
> > 
> > For some domains no extra clocks are needed (ie the clocks enabled by the
> > power domain driver are enough). So an extra flag would be needed then.
> 
> Yes but you have num_clks to detect if a domain has extra clocks. So you
> can use both of these to detect if the clocks are setup correctly. Right?
> 
> >>> +		for (j = 0; j < num_clks; j++) {
> >>> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
> >>> +			struct clk *clk = clks[clk_id];
> >>> +
> >>> +			if (IS_ERR(clk)) {
> >>> +				clk_data[j].clk = NULL;
> >>> +				WARN(1, "clk_id: %d\n", clk_id);
> >>
> >> I think that we should return an error here.
> >>
> > 
> > I don't think letting clock init fail because of this, is a good idea. Too
> > many things rely on working clocks.
> 
> It should never fail and if it does something is badly broken.
> 
> Maybe what we could do ...
> 
> 			if (WARN_ON(IS_ERR(clk))) {

and here..

> 				tegra210_pg_mbist_war[i].clks = NULL;
> 				break;
> 			}
> 
> 			clk_data[j].clk = clk;
> 

..

> >>>  	if (!clks)
> >>> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
> >>>  	tegra_add_of_provider(np);
> >>>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
> >>>  
> >>> +	tegra210_mbist_clk_init();
> >>> +
> >>
> >> Maybe add a print here if the mbist init fails and return. I understand
> >> it may not be a critical failure but it should never fail.
> >>
> > 
> > You mean have the entire clock init fail and undo all the clock registrations?
> > That seems overkill to me. Returning early would only prevent some sleep states
> > from working because tegra_cpu_car_ops will not be initialized then. So I would
> > do a warning then.
> 
> I don't think it is necessary to undo it. Ok, don't worry about
> returning an error here, the warnings should be sufficient.
> 

I don't think there's much value in yet another warning here.

Peter.

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Peter De Schrijver]

On Thu, Jan 25, 2018 at 10:19:08AM +0000, Jon Hunter wrote:
> 
> On 25/01/18 09:02, Peter De Schrijver wrote:
> > On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:
> 
> ...
> 
> >>> +void tegra210_clk_handle_mbist_war(unsigned int id)
> >>> +{
> >>> +	int err;
> >>> +	struct tegra210_domain_mbist_war *mbist_war;
> >>> +
> >>> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
> >>> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
> >>> +		return;
> >>> +	}
> >>> +
> >>> +	mbist_war = &tegra210_pg_mbist_war[id];
> >>> +	if (!mbist_war->handle_lvl2_ovr)
> >>> +		return;
> >>> +
> >>> +	err = mbist_war->handle_lvl2_ovr(mbist_war);
> >>
> >> Why not move the clk_bulk_prepare_enable/disable_unprepare and
> >> mutex_lock/unlock functions into this function around the call to
> >> ->handle_lvl2_ovr to save the duplication of that code in each of the
> >> war functions?
> >>
> > 
> > This could be done yes.
> > 
> >>> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
> >>> +}
> >>
> >> I think that the above function should return an error and we should let
> >> the power-domain power-on fail.
> >>
> > 
> > This would only be useful if the user (tegra_powergate_power_up) would do
> > rollback. I don't think that's done correctly today.
> 
> It does and so I think that we should return an error.
> 

Ok.

> >>> +
> >>> +
> >>>  void tegra210_put_utmipll_in_iddq(void)
> >>>  {
> >>>  	u32 reg;
> >>> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
> >>>  	return 0;
> >>>  }
> >>>  
> >>> +static void tegra210_mbist_clk_init(void)
> >>> +{
> >>> +	int i, j;
> >>> +
> >>> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
> >>> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
> >>> +		struct clk_bulk_data *clk_data;
> >>> +
> >>> +		if (!num_clks)
> >>> +			continue;
> >>> +
> >>> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
> >>> +					 GFP_KERNEL);
> >>> +		if (WARN(!clk_data,
> >>> +			"no space for MBIST WAR clk array for %d\n", i)) {
> >>> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
> >>> +			continue;
> >>> +		}
> >>
> >> Printing error messages on memory allocation failures are not needed and
> >> have been removed from various drivers. So lets no add any error
> >> messages or warnings here.
> >>
> >> Also I think that we should just return an error here and not bother
> >> continuing as there is no point.
> 
> So maybe here just ...
> 
> 		if (WARN_ON(!clk_data))
> 			return -ENOMEM;
> 

Given that we do WARN_ON() here..

> >>> +
> >>> +		tegra210_pg_mbist_war[i].clks = clk_data;
> >>
> >> I think that you should only populate this when all the clocks have been
> >> initialised correctly. You could then use this to check the clocks have
> >> been setup correctly when executing the war.
> >>
> > 
> > For some domains no extra clocks are needed (ie the clocks enabled by the
> > power domain driver are enough). So an extra flag would be needed then.
> 
> Yes but you have num_clks to detect if a domain has extra clocks. So you
> can use both of these to detect if the clocks are setup correctly. Right?
> 
> >>> +		for (j = 0; j < num_clks; j++) {
> >>> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
> >>> +			struct clk *clk = clks[clk_id];
> >>> +
> >>> +			if (IS_ERR(clk)) {
> >>> +				clk_data[j].clk = NULL;
> >>> +				WARN(1, "clk_id: %d\n", clk_id);
> >>
> >> I think that we should return an error here.
> >>
> > 
> > I don't think letting clock init fail because of this, is a good idea. Too
> > many things rely on working clocks.
> 
> It should never fail and if it does something is badly broken.
> 
> Maybe what we could do ...
> 
> 			if (WARN_ON(IS_ERR(clk))) {

and here..

> 				tegra210_pg_mbist_war[i].clks = NULL;
> 				break;
> 			}
> 
> 			clk_data[j].clk = clk;
> 

..

> >>>  	if (!clks)
> >>> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
> >>>  	tegra_add_of_provider(np);
> >>>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
> >>>  
> >>> +	tegra210_mbist_clk_init();
> >>> +
> >>
> >> Maybe add a print here if the mbist init fails and return. I understand
> >> it may not be a critical failure but it should never fail.
> >>
> > 
> > You mean have the entire clock init fail and undo all the clock registrations?
> > That seems overkill to me. Returning early would only prevent some sleep states
> > from working because tegra_cpu_car_ops will not be initialized then. So I would
> > do a warning then.
> 
> I don't think it is necessary to undo it. Ok, don't worry about
> returning an error here, the warnings should be sufficient.
> 

I don't think there's much value in yet another warning here.

Peter.

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Jon Hunter]

On 25/01/18 12:41, Peter De Schrijver wrote:
> On Thu, Jan 25, 2018 at 10:19:08AM +0000, Jon Hunter wrote:
>>
>> On 25/01/18 09:02, Peter De Schrijver wrote:
>>> On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:
>>
>> ...
>>
>>>>> +void tegra210_clk_handle_mbist_war(unsigned int id)
>>>>> +{
>>>>> +	int err;
>>>>> +	struct tegra210_domain_mbist_war *mbist_war;
>>>>> +
>>>>> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
>>>>> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
>>>>> +		return;
>>>>> +	}
>>>>> +
>>>>> +	mbist_war = &tegra210_pg_mbist_war[id];
>>>>> +	if (!mbist_war->handle_lvl2_ovr)
>>>>> +		return;
>>>>> +
>>>>> +	err = mbist_war->handle_lvl2_ovr(mbist_war);
>>>>
>>>> Why not move the clk_bulk_prepare_enable/disable_unprepare and
>>>> mutex_lock/unlock functions into this function around the call to
>>>> ->handle_lvl2_ovr to save the duplication of that code in each of the
>>>> war functions?
>>>>
>>>
>>> This could be done yes.
>>>
>>>>> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
>>>>> +}
>>>>
>>>> I think that the above function should return an error and we should let
>>>> the power-domain power-on fail.
>>>>
>>>
>>> This would only be useful if the user (tegra_powergate_power_up) would do
>>> rollback. I don't think that's done correctly today.
>>
>> It does and so I think that we should return an error.
>>
> 
> Ok.
> 
>>>>> +
>>>>> +
>>>>>  void tegra210_put_utmipll_in_iddq(void)
>>>>>  {
>>>>>  	u32 reg;
>>>>> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
>>>>>  	return 0;
>>>>>  }
>>>>>  
>>>>> +static void tegra210_mbist_clk_init(void)
>>>>> +{
>>>>> +	int i, j;
>>>>> +
>>>>> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
>>>>> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
>>>>> +		struct clk_bulk_data *clk_data;
>>>>> +
>>>>> +		if (!num_clks)
>>>>> +			continue;
>>>>> +
>>>>> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
>>>>> +					 GFP_KERNEL);
>>>>> +		if (WARN(!clk_data,
>>>>> +			"no space for MBIST WAR clk array for %d\n", i)) {
>>>>> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
>>>>> +			continue;
>>>>> +		}
>>>>
>>>> Printing error messages on memory allocation failures are not needed and
>>>> have been removed from various drivers. So lets no add any error
>>>> messages or warnings here.
>>>>
>>>> Also I think that we should just return an error here and not bother
>>>> continuing as there is no point.
>>
>> So maybe here just ...
>>
>> 		if (WARN_ON(!clk_data))
>> 			return -ENOMEM;
>>
> 
> Given that we do WARN_ON() here..
> 
>>>>> +
>>>>> +		tegra210_pg_mbist_war[i].clks = clk_data;
>>>>
>>>> I think that you should only populate this when all the clocks have been
>>>> initialised correctly. You could then use this to check the clocks have
>>>> been setup correctly when executing the war.
>>>>
>>>
>>> For some domains no extra clocks are needed (ie the clocks enabled by the
>>> power domain driver are enough). So an extra flag would be needed then.
>>
>> Yes but you have num_clks to detect if a domain has extra clocks. So you
>> can use both of these to detect if the clocks are setup correctly. Right?
>>
>>>>> +		for (j = 0; j < num_clks; j++) {
>>>>> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
>>>>> +			struct clk *clk = clks[clk_id];
>>>>> +
>>>>> +			if (IS_ERR(clk)) {
>>>>> +				clk_data[j].clk = NULL;
>>>>> +				WARN(1, "clk_id: %d\n", clk_id);
>>>>
>>>> I think that we should return an error here.
>>>>
>>>
>>> I don't think letting clock init fail because of this, is a good idea. Too
>>> many things rely on working clocks.
>>
>> It should never fail and if it does something is badly broken.
>>
>> Maybe what we could do ...
>>
>> 			if (WARN_ON(IS_ERR(clk))) {
> 
> and here..
> 
>> 				tegra210_pg_mbist_war[i].clks = NULL;
>> 				break;
>> 			}
>>
>> 			clk_data[j].clk = clk;
>>
> 
> ..
> 
>>>>>  	if (!clks)
>>>>> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
>>>>>  	tegra_add_of_provider(np);
>>>>>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
>>>>>  
>>>>> +	tegra210_mbist_clk_init();
>>>>> +
>>>>
>>>> Maybe add a print here if the mbist init fails and return. I understand
>>>> it may not be a critical failure but it should never fail.
>>>>
>>>
>>> You mean have the entire clock init fail and undo all the clock registrations?
>>> That seems overkill to me. Returning early would only prevent some sleep states
>>> from working because tegra_cpu_car_ops will not be initialized then. So I would
>>> do a warning then.
>>
>> I don't think it is necessary to undo it. Ok, don't worry about
>> returning an error here, the warnings should be sufficient.
>>
> 
> I don't think there's much value in yet another warning here.

Yes indeed.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 3/4] clk: tegra: MBIST work around for Tegra210

[Jon Hunter]

On 25/01/18 12:41, Peter De Schrijver wrote:
> On Thu, Jan 25, 2018 at 10:19:08AM +0000, Jon Hunter wrote:
>>
>> On 25/01/18 09:02, Peter De Schrijver wrote:
>>> On Wed, Jan 24, 2018 at 09:59:56PM +0000, Jon Hunter wrote:
>>
>> ...
>>
>>>>> +void tegra210_clk_handle_mbist_war(unsigned int id)
>>>>> +{
>>>>> +	int err;
>>>>> +	struct tegra210_domain_mbist_war *mbist_war;
>>>>> +
>>>>> +	if (id >= ARRAY_SIZE(tegra210_pg_mbist_war)) {
>>>>> +		WARN(1, "unknown domain id in MBIST WAR handler\n");
>>>>> +		return;
>>>>> +	}
>>>>> +
>>>>> +	mbist_war = &tegra210_pg_mbist_war[id];
>>>>> +	if (!mbist_war->handle_lvl2_ovr)
>>>>> +		return;
>>>>> +
>>>>> +	err = mbist_war->handle_lvl2_ovr(mbist_war);
>>>>
>>>> Why not move the clk_bulk_prepare_enable/disable_unprepare and
>>>> mutex_lock/unlock functions into this function around the call to
>>>> ->handle_lvl2_ovr to save the duplication of that code in each of the
>>>> war functions?
>>>>
>>>
>>> This could be done yes.
>>>
>>>>> +	WARN(err < 0, "error handling MBIST WAR for domain: %d\n", id);
>>>>> +}
>>>>
>>>> I think that the above function should return an error and we should let
>>>> the power-domain power-on fail.
>>>>
>>>
>>> This would only be useful if the user (tegra_powergate_power_up) would do
>>> rollback. I don't think that's done correctly today.
>>
>> It does and so I think that we should return an error.
>>
> 
> Ok.
> 
>>>>> +
>>>>> +
>>>>>  void tegra210_put_utmipll_in_iddq(void)
>>>>>  {
>>>>>  	u32 reg;
>>>>> @@ -3163,6 +3500,40 @@ static int tegra210_reset_deassert(unsigned long id)
>>>>>  	return 0;
>>>>>  }
>>>>>  
>>>>> +static void tegra210_mbist_clk_init(void)
>>>>> +{
>>>>> +	int i, j;
>>>>> +
>>>>> +	for (i = 0; i < ARRAY_SIZE(tegra210_pg_mbist_war); i++) {
>>>>> +		int num_clks = tegra210_pg_mbist_war[i].num_clks;
>>>>> +		struct clk_bulk_data *clk_data;
>>>>> +
>>>>> +		if (!num_clks)
>>>>> +			continue;
>>>>> +
>>>>> +		clk_data = kmalloc_array(num_clks, sizeof(*clk_data),
>>>>> +					 GFP_KERNEL);
>>>>> +		if (WARN(!clk_data,
>>>>> +			"no space for MBIST WAR clk array for %d\n", i)) {
>>>>> +			tegra210_pg_mbist_war[i].handle_lvl2_ovr = NULL;
>>>>> +			continue;
>>>>> +		}
>>>>
>>>> Printing error messages on memory allocation failures are not needed and
>>>> have been removed from various drivers. So lets no add any error
>>>> messages or warnings here.
>>>>
>>>> Also I think that we should just return an error here and not bother
>>>> continuing as there is no point.
>>
>> So maybe here just ...
>>
>> 		if (WARN_ON(!clk_data))
>> 			return -ENOMEM;
>>
> 
> Given that we do WARN_ON() here..
> 
>>>>> +
>>>>> +		tegra210_pg_mbist_war[i].clks = clk_data;
>>>>
>>>> I think that you should only populate this when all the clocks have been
>>>> initialised correctly. You could then use this to check the clocks have
>>>> been setup correctly when executing the war.
>>>>
>>>
>>> For some domains no extra clocks are needed (ie the clocks enabled by the
>>> power domain driver are enough). So an extra flag would be needed then.
>>
>> Yes but you have num_clks to detect if a domain has extra clocks. So you
>> can use both of these to detect if the clocks are setup correctly. Right?
>>
>>>>> +		for (j = 0; j < num_clks; j++) {
>>>>> +			int clk_id = tegra210_pg_mbist_war[i].clk_init_data[j];
>>>>> +			struct clk *clk = clks[clk_id];
>>>>> +
>>>>> +			if (IS_ERR(clk)) {
>>>>> +				clk_data[j].clk = NULL;
>>>>> +				WARN(1, "clk_id: %d\n", clk_id);
>>>>
>>>> I think that we should return an error here.
>>>>
>>>
>>> I don't think letting clock init fail because of this, is a good idea. Too
>>> many things rely on working clocks.
>>
>> It should never fail and if it does something is badly broken.
>>
>> Maybe what we could do ...
>>
>> 			if (WARN_ON(IS_ERR(clk))) {
> 
> and here..
> 
>> 				tegra210_pg_mbist_war[i].clks = NULL;
>> 				break;
>> 			}
>>
>> 			clk_data[j].clk = clk;
>>
> 
> ..
> 
>>>>>  	if (!clks)
>>>>> @@ -3233,6 +3622,8 @@ static void __init tegra210_clock_init(struct device_node *np)
>>>>>  	tegra_add_of_provider(np);
>>>>>  	tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
>>>>>  
>>>>> +	tegra210_mbist_clk_init();
>>>>> +
>>>>
>>>> Maybe add a print here if the mbist init fails and return. I understand
>>>> it may not be a critical failure but it should never fail.
>>>>
>>>
>>> You mean have the entire clock init fail and undo all the clock registrations?
>>> That seems overkill to me. Returning early would only prevent some sleep states
>>> from working because tegra_cpu_car_ops will not be initialized then. So I would
>>> do a warning then.
>>
>> I don't think it is necessary to undo it. Ok, don't worry about
>> returning an error here, the warnings should be sufficient.
>>
> 
> I don't think there's much value in yet another warning here.

Yes indeed.

Cheers
Jon

-- 
nvpublic

[PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Peter De Schrijver]

Apply the memory built-in self test work around when ungating certain
Tegra210 power domains.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/soc/tegra/pmc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index ce62a47..c4eff4b 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -153,6 +153,7 @@ struct tegra_pmc_soc {
 
 	bool has_tsense_reset;
 	bool has_gpu_clamps;
+	bool needs_mbist_war;
 
 	const struct tegra_io_pad_soc *io_pads;
 	unsigned int num_io_pads;
@@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
 
 	usleep_range(10, 20);
 
+	if (pg->pmc->soc->needs_mbist_war)
+		tegra210_clk_handle_mbist_war(pg->id);
+
 	if (disable_clocks)
 		tegra_powergate_disable_clocks(pg);
 
@@ -1815,6 +1819,7 @@ static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc,
 	.cpu_powergates = tegra210_cpu_powergates,
 	.has_tsense_reset = true,
 	.has_gpu_clamps = true,
+	.needs_mbist_war = true,
 	.num_io_pads = ARRAY_SIZE(tegra210_io_pads),
 	.io_pads = tegra210_io_pads,
 	.regs = &tegra20_pmc_regs,
-- 
1.9.1

[PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Peter De Schrijver]

Apply the memory built-in self test work around when ungating certain
Tegra210 power domains.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/soc/tegra/pmc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index ce62a47..c4eff4b 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -153,6 +153,7 @@ struct tegra_pmc_soc {
 
 	bool has_tsense_reset;
 	bool has_gpu_clamps;
+	bool needs_mbist_war;
 
 	const struct tegra_io_pad_soc *io_pads;
 	unsigned int num_io_pads;
@@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
 
 	usleep_range(10, 20);
 
+	if (pg->pmc->soc->needs_mbist_war)
+		tegra210_clk_handle_mbist_war(pg->id);
+
 	if (disable_clocks)
 		tegra_powergate_disable_clocks(pg);
 
@@ -1815,6 +1819,7 @@ static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc,
 	.cpu_powergates = tegra210_cpu_powergates,
 	.has_tsense_reset = true,
 	.has_gpu_clamps = true,
+	.needs_mbist_war = true,
 	.num_io_pads = ARRAY_SIZE(tegra210_io_pads),
 	.io_pads = tegra210_io_pads,
 	.regs = &tegra20_pmc_regs,
-- 
1.9.1

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> Apply the memory built-in self test work around when ungating certain
> Tegra210 power domains.

Nit-pick .. typo in $subject.

> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/soc/tegra/pmc.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> index ce62a47..c4eff4b 100644
> --- a/drivers/soc/tegra/pmc.c
> +++ b/drivers/soc/tegra/pmc.c
> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
>  
>  	bool has_tsense_reset;
>  	bool has_gpu_clamps;
> +	bool needs_mbist_war;
>  
>  	const struct tegra_io_pad_soc *io_pads;
>  	unsigned int num_io_pads;
> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
>  
>  	usleep_range(10, 20);
>  
> +	if (pg->pmc->soc->needs_mbist_war)
> +		tegra210_clk_handle_mbist_war(pg->id);
> +

Be good if we could return an error from the above function.

>  	if (disable_clocks)
>  		tegra_powergate_disable_clocks(pg);
>  
> @@ -1815,6 +1819,7 @@ static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc,
>  	.cpu_powergates = tegra210_cpu_powergates,
>  	.has_tsense_reset = true,
>  	.has_gpu_clamps = true,
> +	.needs_mbist_war = true,
>  	.num_io_pads = ARRAY_SIZE(tegra210_io_pads),
>  	.io_pads = tegra210_io_pads,
>  	.regs = &tegra20_pmc_regs,
> 

Otherwise looks good to me.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Jon Hunter]

On 23/01/18 09:22, Peter De Schrijver wrote:
> Apply the memory built-in self test work around when ungating certain
> Tegra210 power domains.

Nit-pick .. typo in $subject.

> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> ---
>  drivers/soc/tegra/pmc.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> index ce62a47..c4eff4b 100644
> --- a/drivers/soc/tegra/pmc.c
> +++ b/drivers/soc/tegra/pmc.c
> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
>  
>  	bool has_tsense_reset;
>  	bool has_gpu_clamps;
> +	bool needs_mbist_war;
>  
>  	const struct tegra_io_pad_soc *io_pads;
>  	unsigned int num_io_pads;
> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
>  
>  	usleep_range(10, 20);
>  
> +	if (pg->pmc->soc->needs_mbist_war)
> +		tegra210_clk_handle_mbist_war(pg->id);
> +

Be good if we could return an error from the above function.

>  	if (disable_clocks)
>  		tegra_powergate_disable_clocks(pg);
>  
> @@ -1815,6 +1819,7 @@ static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc,
>  	.cpu_powergates = tegra210_cpu_powergates,
>  	.has_tsense_reset = true,
>  	.has_gpu_clamps = true,
> +	.needs_mbist_war = true,
>  	.num_io_pads = ARRAY_SIZE(tegra210_io_pads),
>  	.io_pads = tegra210_io_pads,
>  	.regs = &tegra20_pmc_regs,
> 

Otherwise looks good to me.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Peter De Schrijver]

On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
> 
> On 23/01/18 09:22, Peter De Schrijver wrote:
> > Apply the memory built-in self test work around when ungating certain
> > Tegra210 power domains.
> 
> Nit-pick .. typo in $subject.
> 
> > Signed-off-by: Peter De Schrijver <pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> > ---
> >  drivers/soc/tegra/pmc.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> > 
> > diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> > index ce62a47..c4eff4b 100644
> > --- a/drivers/soc/tegra/pmc.c
> > +++ b/drivers/soc/tegra/pmc.c
> > @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
> >  
> >  	bool has_tsense_reset;
> >  	bool has_gpu_clamps;
> > +	bool needs_mbist_war;
> >  
> >  	const struct tegra_io_pad_soc *io_pads;
> >  	unsigned int num_io_pads;
> > @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
> >  
> >  	usleep_range(10, 20);
> >  
> > +	if (pg->pmc->soc->needs_mbist_war)
> > +		tegra210_clk_handle_mbist_war(pg->id);
> > +
> 
> Be good if we could return an error from the above function.
> 

We need to also undo whatever we did before then. 

> >  	if (disable_clocks)
> >  		tegra_powergate_disable_clocks(pg);
> >  
> > @@ -1815,6 +1819,7 @@ static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc,
> >  	.cpu_powergates = tegra210_cpu_powergates,
> >  	.has_tsense_reset = true,
> >  	.has_gpu_clamps = true,
> > +	.needs_mbist_war = true,
> >  	.num_io_pads = ARRAY_SIZE(tegra210_io_pads),
> >  	.io_pads = tegra210_io_pads,
> >  	.regs = &tegra20_pmc_regs,
> > 
> 
> Otherwise looks good to me.
> 
> Cheers
> Jon
> 
> -- 
> nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Peter De Schrijver]

On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
> 
> On 23/01/18 09:22, Peter De Schrijver wrote:
> > Apply the memory built-in self test work around when ungating certain
> > Tegra210 power domains.
> 
> Nit-pick .. typo in $subject.
> 
> > Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> > ---
> >  drivers/soc/tegra/pmc.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> > 
> > diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> > index ce62a47..c4eff4b 100644
> > --- a/drivers/soc/tegra/pmc.c
> > +++ b/drivers/soc/tegra/pmc.c
> > @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
> >  
> >  	bool has_tsense_reset;
> >  	bool has_gpu_clamps;
> > +	bool needs_mbist_war;
> >  
> >  	const struct tegra_io_pad_soc *io_pads;
> >  	unsigned int num_io_pads;
> > @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
> >  
> >  	usleep_range(10, 20);
> >  
> > +	if (pg->pmc->soc->needs_mbist_war)
> > +		tegra210_clk_handle_mbist_war(pg->id);
> > +
> 
> Be good if we could return an error from the above function.
> 

We need to also undo whatever we did before then. 

> >  	if (disable_clocks)
> >  		tegra_powergate_disable_clocks(pg);
> >  
> > @@ -1815,6 +1819,7 @@ static void tegra20_pmc_setup_irq_polarity(struct tegra_pmc *pmc,
> >  	.cpu_powergates = tegra210_cpu_powergates,
> >  	.has_tsense_reset = true,
> >  	.has_gpu_clamps = true,
> > +	.needs_mbist_war = true,
> >  	.num_io_pads = ARRAY_SIZE(tegra210_io_pads),
> >  	.io_pads = tegra210_io_pads,
> >  	.regs = &tegra20_pmc_regs,
> > 
> 
> Otherwise looks good to me.
> 
> Cheers
> Jon
> 
> -- 
> nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Jon Hunter]

On 25/01/18 10:06, Peter De Schrijver wrote:
> On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
>>
>> On 23/01/18 09:22, Peter De Schrijver wrote:
>>> Apply the memory built-in self test work around when ungating certain
>>> Tegra210 power domains.
>>
>> Nit-pick .. typo in $subject.
>>
>>> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
>>> ---
>>>  drivers/soc/tegra/pmc.c | 5 +++++
>>>  1 file changed, 5 insertions(+)
>>>
>>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
>>> index ce62a47..c4eff4b 100644
>>> --- a/drivers/soc/tegra/pmc.c
>>> +++ b/drivers/soc/tegra/pmc.c
>>> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
>>>  
>>>  	bool has_tsense_reset;
>>>  	bool has_gpu_clamps;
>>> +	bool needs_mbist_war;
>>>  
>>>  	const struct tegra_io_pad_soc *io_pads;
>>>  	unsigned int num_io_pads;
>>> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
>>>  
>>>  	usleep_range(10, 20);
>>>  
>>> +	if (pg->pmc->soc->needs_mbist_war)
>>> +		tegra210_clk_handle_mbist_war(pg->id);
>>> +
>>
>> Be good if we could return an error from the above function.
>>
> 
> We need to also undo whatever we did before then. 

I think it is fine if on error you 'goto disable_clks'.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Jon Hunter]

On 25/01/18 10:06, Peter De Schrijver wrote:
> On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
>>
>> On 23/01/18 09:22, Peter De Schrijver wrote:
>>> Apply the memory built-in self test work around when ungating certain
>>> Tegra210 power domains.
>>
>> Nit-pick .. typo in $subject.
>>
>>> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
>>> ---
>>>  drivers/soc/tegra/pmc.c | 5 +++++
>>>  1 file changed, 5 insertions(+)
>>>
>>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
>>> index ce62a47..c4eff4b 100644
>>> --- a/drivers/soc/tegra/pmc.c
>>> +++ b/drivers/soc/tegra/pmc.c
>>> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
>>>  
>>>  	bool has_tsense_reset;
>>>  	bool has_gpu_clamps;
>>> +	bool needs_mbist_war;
>>>  
>>>  	const struct tegra_io_pad_soc *io_pads;
>>>  	unsigned int num_io_pads;
>>> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
>>>  
>>>  	usleep_range(10, 20);
>>>  
>>> +	if (pg->pmc->soc->needs_mbist_war)
>>> +		tegra210_clk_handle_mbist_war(pg->id);
>>> +
>>
>> Be good if we could return an error from the above function.
>>
> 
> We need to also undo whatever we did before then. 

I think it is fine if on error you 'goto disable_clks'.

Cheers
Jon

-- 
nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Peter De Schrijver]

On Thu, Jan 25, 2018 at 10:57:36AM +0000, Jon Hunter wrote:
> 
> On 25/01/18 10:06, Peter De Schrijver wrote:
> > On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
> >>
> >> On 23/01/18 09:22, Peter De Schrijver wrote:
> >>> Apply the memory built-in self test work around when ungating certain
> >>> Tegra210 power domains.
> >>
> >> Nit-pick .. typo in $subject.
> >>
> >>> Signed-off-by: Peter De Schrijver <pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> >>> ---
> >>>  drivers/soc/tegra/pmc.c | 5 +++++
> >>>  1 file changed, 5 insertions(+)
> >>>
> >>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> >>> index ce62a47..c4eff4b 100644
> >>> --- a/drivers/soc/tegra/pmc.c
> >>> +++ b/drivers/soc/tegra/pmc.c
> >>> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
> >>>  
> >>>  	bool has_tsense_reset;
> >>>  	bool has_gpu_clamps;
> >>> +	bool needs_mbist_war;
> >>>  
> >>>  	const struct tegra_io_pad_soc *io_pads;
> >>>  	unsigned int num_io_pads;
> >>> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
> >>>  
> >>>  	usleep_range(10, 20);
> >>>  
> >>> +	if (pg->pmc->soc->needs_mbist_war)
> >>> +		tegra210_clk_handle_mbist_war(pg->id);
> >>> +
> >>
> >> Be good if we could return an error from the above function.
> >>
> > 
> > We need to also undo whatever we did before then. 
> 
> I think it is fine if on error you 'goto disable_clks'.

Shouldn't we do this for tegra_powergate_reset_deassert() failure as well then?
Also in case of tegra_powergate_enable_clocks() failure we should probably jump
to powergate_off because tegra_powergate_enable_clocks() will disable the
already enabled clocks on failure.

Peter.

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Peter De Schrijver]

On Thu, Jan 25, 2018 at 10:57:36AM +0000, Jon Hunter wrote:
> 
> On 25/01/18 10:06, Peter De Schrijver wrote:
> > On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
> >>
> >> On 23/01/18 09:22, Peter De Schrijver wrote:
> >>> Apply the memory built-in self test work around when ungating certain
> >>> Tegra210 power domains.
> >>
> >> Nit-pick .. typo in $subject.
> >>
> >>> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> >>> ---
> >>>  drivers/soc/tegra/pmc.c | 5 +++++
> >>>  1 file changed, 5 insertions(+)
> >>>
> >>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
> >>> index ce62a47..c4eff4b 100644
> >>> --- a/drivers/soc/tegra/pmc.c
> >>> +++ b/drivers/soc/tegra/pmc.c
> >>> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
> >>>  
> >>>  	bool has_tsense_reset;
> >>>  	bool has_gpu_clamps;
> >>> +	bool needs_mbist_war;
> >>>  
> >>>  	const struct tegra_io_pad_soc *io_pads;
> >>>  	unsigned int num_io_pads;
> >>> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
> >>>  
> >>>  	usleep_range(10, 20);
> >>>  
> >>> +	if (pg->pmc->soc->needs_mbist_war)
> >>> +		tegra210_clk_handle_mbist_war(pg->id);
> >>> +
> >>
> >> Be good if we could return an error from the above function.
> >>
> > 
> > We need to also undo whatever we did before then. 
> 
> I think it is fine if on error you 'goto disable_clks'.

Shouldn't we do this for tegra_powergate_reset_deassert() failure as well then?
Also in case of tegra_powergate_enable_clocks() failure we should probably jump
to powergate_off because tegra_powergate_enable_clocks() will disable the
already enabled clocks on failure.

Peter.

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Jon Hunter]

On 25/01/18 12:26, Peter De Schrijver wrote:
> On Thu, Jan 25, 2018 at 10:57:36AM +0000, Jon Hunter wrote:
>>
>> On 25/01/18 10:06, Peter De Schrijver wrote:
>>> On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
>>>>
>>>> On 23/01/18 09:22, Peter De Schrijver wrote:
>>>>> Apply the memory built-in self test work around when ungating certain
>>>>> Tegra210 power domains.
>>>>
>>>> Nit-pick .. typo in $subject.
>>>>
>>>>> Signed-off-by: Peter De Schrijver <pdeschrijver-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
>>>>> ---
>>>>>  drivers/soc/tegra/pmc.c | 5 +++++
>>>>>  1 file changed, 5 insertions(+)
>>>>>
>>>>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
>>>>> index ce62a47..c4eff4b 100644
>>>>> --- a/drivers/soc/tegra/pmc.c
>>>>> +++ b/drivers/soc/tegra/pmc.c
>>>>> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
>>>>>  
>>>>>  	bool has_tsense_reset;
>>>>>  	bool has_gpu_clamps;
>>>>> +	bool needs_mbist_war;
>>>>>  
>>>>>  	const struct tegra_io_pad_soc *io_pads;
>>>>>  	unsigned int num_io_pads;
>>>>> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
>>>>>  
>>>>>  	usleep_range(10, 20);
>>>>>  
>>>>> +	if (pg->pmc->soc->needs_mbist_war)
>>>>> +		tegra210_clk_handle_mbist_war(pg->id);
>>>>> +
>>>>
>>>> Be good if we could return an error from the above function.
>>>>
>>>
>>> We need to also undo whatever we did before then. 
>>
>> I think it is fine if on error you 'goto disable_clks'.
> 
> Shouldn't we do this for tegra_powergate_reset_deassert() failure as well then?
> Also in case of tegra_powergate_enable_clocks() failure we should probably jump
> to powergate_off because tegra_powergate_enable_clocks() will disable the
> already enabled clocks on failure.

Yes that looks like a bug in the existing code and we should fix that.
Good catch.

Jon

-- 
nvpublic

Re: [PATCH v3 4/4] soc/tegra: pmc: apply MBIST work around fo Tegra210

[Jon Hunter]

On 25/01/18 12:26, Peter De Schrijver wrote:
> On Thu, Jan 25, 2018 at 10:57:36AM +0000, Jon Hunter wrote:
>>
>> On 25/01/18 10:06, Peter De Schrijver wrote:
>>> On Wed, Jan 24, 2018 at 10:43:45PM +0000, Jon Hunter wrote:
>>>>
>>>> On 23/01/18 09:22, Peter De Schrijver wrote:
>>>>> Apply the memory built-in self test work around when ungating certain
>>>>> Tegra210 power domains.
>>>>
>>>> Nit-pick .. typo in $subject.
>>>>
>>>>> Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
>>>>> ---
>>>>>  drivers/soc/tegra/pmc.c | 5 +++++
>>>>>  1 file changed, 5 insertions(+)
>>>>>
>>>>> diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
>>>>> index ce62a47..c4eff4b 100644
>>>>> --- a/drivers/soc/tegra/pmc.c
>>>>> +++ b/drivers/soc/tegra/pmc.c
>>>>> @@ -153,6 +153,7 @@ struct tegra_pmc_soc {
>>>>>  
>>>>>  	bool has_tsense_reset;
>>>>>  	bool has_gpu_clamps;
>>>>> +	bool needs_mbist_war;
>>>>>  
>>>>>  	const struct tegra_io_pad_soc *io_pads;
>>>>>  	unsigned int num_io_pads;
>>>>> @@ -431,6 +432,9 @@ static int tegra_powergate_power_up(struct tegra_powergate *pg,
>>>>>  
>>>>>  	usleep_range(10, 20);
>>>>>  
>>>>> +	if (pg->pmc->soc->needs_mbist_war)
>>>>> +		tegra210_clk_handle_mbist_war(pg->id);
>>>>> +
>>>>
>>>> Be good if we could return an error from the above function.
>>>>
>>>
>>> We need to also undo whatever we did before then. 
>>
>> I think it is fine if on error you 'goto disable_clks'.
> 
> Shouldn't we do this for tegra_powergate_reset_deassert() failure as well then?
> Also in case of tegra_powergate_enable_clocks() failure we should probably jump
> to powergate_off because tegra_powergate_enable_clocks() will disable the
> already enabled clocks on failure.

Yes that looks like a bug in the existing code and we should fix that.
Good catch.

Jon

-- 
nvpublic