[U-Boot] [PATCH] arm, davinci: add PLL0 prediv to da850 lowlevel setup

[U-Boot] [PATCH] arm, davinci: add PLL0 prediv to da850 lowlevel setup

[Ben Gardiner]

The OMAP-L138 has a pre-divider available on PLL0.

Add support to da850_lowlevel.c for configuring PLL0's pre-divider. This is
to achieve certain OPP's -- e.g. the 372MHz OPP used also by Linux.

Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca>
Cc: Christian Riesch <christian.riesch@omicron.at>
CC: Heiko Schocher <hs@denx.de>
Cc: Sandeep Paulraj <s-paulraj@ti.com>
Cc: Tom Rini <tom.rini@gmail.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
---
 arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c |    7 +++++++
 arch/arm/include/asm/arch-davinci/pll_defs.h    |    3 ++-
 2 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c b/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c
index a532f8a..eec06bc 100644
--- a/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c
+++ b/arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c
@@ -85,6 +85,13 @@ int da850_pll_init(struct davinci_pllc_regs *reg, unsigned long pllmult)
 	/* Enable the PLL from Disable Mode PLLDIS bit to 0 */
 	clrbits_le32(&reg->pllctl, PLLCTL_PLLDIS);
 
+#if defined(CONFIG_SYS_DA850_PLL0_PREDIV)
+	/* program the prediv */
+	if (reg == davinci_pllc0_regs && CONFIG_SYS_DA850_PLL0_PREDIV)
+		writel((PLL_DIVEN | CONFIG_SYS_DA850_PLL0_PREDIV),
+			&reg->prediv);
+#endif
+
 	/* Program the required multiplier value in PLLM */
 	writel(pllmult, &reg->pllm);
 
diff --git a/arch/arm/include/asm/arch-davinci/pll_defs.h b/arch/arm/include/asm/arch-davinci/pll_defs.h
index f1396e3..1c8d83f 100644
--- a/arch/arm/include/asm/arch-davinci/pll_defs.h
+++ b/arch/arm/include/asm/arch-davinci/pll_defs.h
@@ -68,7 +68,8 @@ struct dv_pll_regs {
 #define PLLCTL_RES_9	(1 << 8)
 #define PLLCTL_EXTCLKSRC	(1 << 9)
 
-#define PLL_POSTDEN	(1 << 15)
+#define PLL_DIVEN	(1 << 15)
+#define PLL_POSTDEN	PLL_DIVEN
 
 #define PLL_SCSCFG3_DIV45PENA	(1 << 2)
 #define PLL_SCSCFG3_EMA_CLKSRC	(1 << 1)
-- 
1.7.4.1

[U-Boot] [PATCH] arm, davinci: add PLL0 prediv to da850 lowlevel setup

[Heiko Schocher]

Hello Ben,

Ben Gardiner wrote:
> The OMAP-L138 has a pre-divider available on PLL0.
> 
> Add support to da850_lowlevel.c for configuring PLL0's pre-divider. This is
> to achieve certain OPP's -- e.g. the 372MHz OPP used also by Linux.
> 
> Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca>
> Cc: Christian Riesch <christian.riesch@omicron.at>
> CC: Heiko Schocher <hs@denx.de>
> Cc: Sandeep Paulraj <s-paulraj@ti.com>
> Cc: Tom Rini <tom.rini@gmail.com>
> Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
> ---
>  arch/arm/cpu/arm926ejs/davinci/da850_lowlevel.c |    7 +++++++
>  arch/arm/include/asm/arch-davinci/pll_defs.h    |    3 ++-
>  2 files changed, 9 insertions(+), 1 deletions(-)

Acked-by: Heiko Schocher <hs@denx.de>

bye,
Heiko
-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

[U-Boot] [PATCH] arm, davinci: add PLL0 prediv to da850 lowlevel setup

[Christian Riesch]

Hello Ben,

On Mon, Jan 16, 2012 at 6:43 PM, Ben Gardiner
<bengardiner@nanometrics.ca> wrote:
> The OMAP-L138 has a pre-divider available on PLL0.
>
> Add support to da850_lowlevel.c for configuring PLL0's pre-divider. This is
> to achieve certain OPP's -- e.g. the 372MHz OPP used also by Linux.

I noticed that that pre-divider configuration was missing while
working on the lowlevel setup, but then I forgot to add it (and I was
fine with the default)... Thank you for adding it!

Acked-by: Christian Riesch <christian.riesch@omicron.at>

Regards, Christian

[U-Boot] [PATCH] arm, davinci: add PLL0 prediv to da850 lowlevel setup

[Tom Rini]

On Mon, Jan 16, 2012 at 10:43 AM, Ben Gardiner
<bengardiner@nanometrics.ca> wrote:
> The OMAP-L138 has a pre-divider available on PLL0.
>
> Add support to da850_lowlevel.c for configuring PLL0's pre-divider. This is
> to achieve certain OPP's -- e.g. the 372MHz OPP used also by Linux.
>
> Signed-off-by: Ben Gardiner <bengardiner@nanometrics.ca>
> Cc: Christian Riesch <christian.riesch@omicron.at>
> CC: Heiko Schocher <hs@denx.de>
> Cc: Sandeep Paulraj <s-paulraj@ti.com>
> Cc: Tom Rini <tom.rini@gmail.com>
> Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>

Applied to u-boot-ti/master, thanks!

-- 
Tom