[PATCH v8 0/7] clk/resets: baikal-t1: Add DDR/PCIe resets and xGMAC/SATA fixes

[PATCH v8 0/7] clk/resets: baikal-t1: Add DDR/PCIe resets and xGMAC/SATA fixes

[Serge Semin]

Folks! It has been over four months since the first series submission for
review. Please merge it in.

Short summary regarding this patchset. The series starts from fixing of
the clocks glitching cause by the Renesas 5P49V6901 chip in some
circumstances. Afterwards a few more modifications are introduced to
finally finish the Baikal-T1 CCU unit support up and prepare the code
before adding the Baikal-T1 PCIe/xGMAC support. First of all it turned out
I specified wrong DW xGMAC PTP reference clock divider in my initial
patches. It must be 8, not 10. Secondly I was wrong to add a joint xGMAC
Ref and PTP clock instead of having them separately defined.  The SoC
manual describes these clocks as separate fixed clock wrappers. Finally
in order to close the SoC clock/reset support up we need to add the DDR
and PCIe interfaces reset controls support. It's done in two steps. First
I've moved the reset-controls-related code into a dedicated module. Then
the DDR/PCIe reset-control functionality is added. As the series
finalization we've decided to convert the Baikal-T1 clock/reset source
drivers to mainly being the platform device driver and pre-initialize the
basic clocks only at the early kernel boot stages.

Link: https://lore.kernel.org/linux-pci/20220324010905.15589-1-Sergey.Semin@baikalelectronics.ru/
Changelog v2:
- Resubmit the series with adding @Philipp to the list of the recipients.

Link: https://lore.kernel.org/linux-pci/20220330144320.27039-1-Sergey.Semin@baikalelectronics.ru/
Changelog v3:
- No comments. Just resend the series.
- Rebased from v5.17 onto v5.18-rc3.

Link: https://lore.kernel.org/linux-clk/20220503205722.24755-1-Sergey.Semin@baikalelectronics.ru/
Changelog v4:
- Completely split the CCU Dividers and Resets functionality up. (@Stephen)
- Add a new fixes patch: "clk: baikal-t1: Actually enable SATA internal
  ref clock".
- Add a new fixes patch: "reset: Fix devm bulk optional exclusive control
  getter".
- Add a new fixes patch: "clk: vc5: Fix 5P49V6901 outputs disabling when
  enabling FOD".
- Add a new feagure patch: "clk: baikal-t1: Convert to platform device
  driver".
- Change the internal clock ID to the XGMAC-referred name.
- Rebase onto the kernel v5.18.

Link: https://lore.kernel.org/lkml/20220610072124.8714-1-Sergey.Semin@baikalelectronics.ru/
Changelog v5:
- Just resend.
- Rebase onto the kernel v5.19-rcX.

Link: https://lore.kernel.org/linux-clk/20220624141853.7417-1-Sergey.Semin@baikalelectronics.ru/
Changelog v6:
- Drop the patch
  [PATCH RESEND v5 1/8] reset: Fix devm bulk optional exclusive control getter
  since it has already been accepted by @Philipp.
- Refactor the reset-control code to support the linear reset IDs only.
  (@Philipp)
- Combine the reset-related code into a single file. (@Philipp)
- Drop CCU_DIV_RST_MAP() macro. It's no longer used.

Link: https://lore.kernel.org/linux-clk/20220708192725.9501-1-Sergey.Semin@baikalelectronics.ru/
Changelog v7:
- Fix "Alignment should match open parenthesis" warning for the
  pr_err() method invocations. (@Philipp)
- Drop empty line from the sys_rst_info structure initialization block.
  (@Philipp)

Link: https://lore.kernel.org/linux-clk/20220711154433.15415-1-Sergey.Semin@baikalelectronics.ru/
Changelog v8:
- Fix "sef-deasserted" spelling in the CLK_BT1_CCU_RST config help
  text. (@Randy)

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: linux-clk@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

Serge Semin (7):
  clk: vc5: Fix 5P49V6901 outputs disabling when enabling FOD
  clk: baikal-t1: Fix invalid xGMAC PTP clock divider
  clk: baikal-t1: Add shared xGMAC ref/ptp clocks internal parent
  clk: baikal-t1: Add SATA internal ref clock buffer
  clk: baikal-t1: Move reset-controls code into a dedicated module
  clk: baikal-t1: Add DDR/PCIe directly controlled resets support
  clk: baikal-t1: Convert to platform device driver

 drivers/clk/baikal-t1/Kconfig       |  12 +-
 drivers/clk/baikal-t1/Makefile      |   1 +
 drivers/clk/baikal-t1/ccu-div.c     |  84 +++++++--
 drivers/clk/baikal-t1/ccu-div.h     |  17 +-
 drivers/clk/baikal-t1/ccu-pll.h     |   8 +
 drivers/clk/baikal-t1/ccu-rst.c     | 217 +++++++++++++++++++++++
 drivers/clk/baikal-t1/ccu-rst.h     |  67 +++++++
 drivers/clk/baikal-t1/clk-ccu-div.c | 263 ++++++++++++++++------------
 drivers/clk/baikal-t1/clk-ccu-pll.c | 128 +++++++++++---
 drivers/clk/clk-versaclock5.c       |   2 +-
 include/dt-bindings/reset/bt1-ccu.h |   9 +
 11 files changed, 647 insertions(+), 161 deletions(-)
 create mode 100644 drivers/clk/baikal-t1/ccu-rst.c
 create mode 100644 drivers/clk/baikal-t1/ccu-rst.h

-- 
2.35.1

[PATCH v8 1/7] clk: vc5: Fix 5P49V6901 outputs disabling when enabling FOD

[Serge Semin]

We have discovered random glitches during the system boot up procedure.
The problem investigation led us to the weird outcomes: when none of the
Renesas 5P49V6901 ports are explicitly enabled by the kernel driver, the
glitches disappeared. It was a mystery since the SoC external clock
domains were fed with different 5P49V6901 outputs. The driver code didn't
seem like bogus either. We almost despaired to find out a root cause when
the solution has been found for a more modern revision of the chip. It
turned out the 5P49V6901 clock generator stopped its output for a short
period of time during the VC5_OUT_DIV_CONTROL register writing. The same
problem was found for the 5P49V6965 revision of the chip and was
successfully fixed in commit fc336ae622df ("clk: vc5: fix output disabling
when enabling a FOD") by enabling the "bypass_sync" flag hidden inside
"Unused Factory Reserved Register". Even though the 5P49V6901 registers
description and programming guide doesn't provide any intel regarding that
flag, setting it up anyway in the officially unused register completely
eliminated the denoted glitches. Thus let's activate the functionality
submitted in commit fc336ae622df ("clk: vc5: fix output disabling when
enabling a FOD") for the Renesas 5P49V6901 chip too in order to remove the
ports implicit inter-dependency.

Fixes: dbf6b16f5683 ("clk: vc5: Add support for IDT VersaClock 5P49V6901")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>

---

Changelog v4:
- This is a new patch added on v4 lap of the series.

Changelog v5:
- Fix some grammar mistakes in the commit log. (@Sergey Shtylyov)
---
 drivers/clk/clk-versaclock5.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/clk-versaclock5.c b/drivers/clk/clk-versaclock5.c
index e7be3e54b9be..03cfef494b49 100644
--- a/drivers/clk/clk-versaclock5.c
+++ b/drivers/clk/clk-versaclock5.c
@@ -1204,7 +1204,7 @@ static const struct vc5_chip_info idt_5p49v6901_info = {
 	.model = IDT_VC6_5P49V6901,
 	.clk_fod_cnt = 4,
 	.clk_out_cnt = 5,
-	.flags = VC5_HAS_PFD_FREQ_DBL,
+	.flags = VC5_HAS_PFD_FREQ_DBL | VC5_HAS_BYPASS_SYNC_BIT,
 };
 
 static const struct vc5_chip_info idt_5p49v6965_info = {
-- 
2.35.1

[PATCH v8 2/7] clk: baikal-t1: Fix invalid xGMAC PTP clock divider

[Serge Semin]

Most likely due to copy-paste mistake the divider has been set to 10 while
according to the SoC reference manual it's supposed to be 8 thus having
PTP clock frequency of 156.25 MHz.

Fixes: 353afa3a8d2e ("clk: Add Baikal-T1 CCU Dividers driver")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
---
 drivers/clk/baikal-t1/clk-ccu-div.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/baikal-t1/clk-ccu-div.c b/drivers/clk/baikal-t1/clk-ccu-div.c
index f141fda12b09..ea77eec40ddd 100644
--- a/drivers/clk/baikal-t1/clk-ccu-div.c
+++ b/drivers/clk/baikal-t1/clk-ccu-div.c
@@ -207,7 +207,7 @@ static const struct ccu_div_info sys_info[] = {
 	CCU_DIV_GATE_INFO(CCU_SYS_XGMAC_REF_CLK, "sys_xgmac_ref_clk",
 			  "eth_clk", CCU_SYS_XGMAC_BASE, 8),
 	CCU_DIV_FIXED_INFO(CCU_SYS_XGMAC_PTP_CLK, "sys_xgmac_ptp_clk",
-			   "eth_clk", 10),
+			   "eth_clk", 8),
 	CCU_DIV_GATE_INFO(CCU_SYS_USB_CLK, "sys_usb_clk",
 			  "eth_clk", CCU_SYS_USB_BASE, 10),
 	CCU_DIV_VAR_INFO(CCU_SYS_PVT_CLK, "sys_pvt_clk",
-- 
2.35.1

[PATCH v8 3/7] clk: baikal-t1: Add shared xGMAC ref/ptp clocks internal parent

[Serge Semin]

Baikal-T1 CCU reference manual says that both xGMAC reference and xGMAC
PTP clocks are generated by two different wrappers with the same constant
divider thus each producing a 156.25 MHz signal. But for some reason both
of these clock sources are gated by a single switch-flag in the CCU
registers space - CCU_SYS_XGMAC_BASE.BIT(0). In order to make the clocks
handled independently we need to define a shared parental gate so the base
clock signal would be switched off only if both of the child-clocks are
disabled.

Note the ID is intentionally set to -2 since we are going to add a one
more internal clock identifier in the next commit.

Fixes: 353afa3a8d2e ("clk: Add Baikal-T1 CCU Dividers driver")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>

---

Changelog v4:
- Change the ID macro name to the more descriptive CCU_SYS_XGMAC_CLK.
---
 drivers/clk/baikal-t1/ccu-div.c     | 1 +
 drivers/clk/baikal-t1/ccu-div.h     | 6 ++++++
 drivers/clk/baikal-t1/clk-ccu-div.c | 8 +++++---
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/baikal-t1/ccu-div.c b/drivers/clk/baikal-t1/ccu-div.c
index 4062092d67f9..bbfa3526ee10 100644
--- a/drivers/clk/baikal-t1/ccu-div.c
+++ b/drivers/clk/baikal-t1/ccu-div.c
@@ -579,6 +579,7 @@ struct ccu_div *ccu_div_hw_register(const struct ccu_div_init_data *div_init)
 		goto err_free_div;
 	}
 	parent_data.fw_name = div_init->parent_name;
+	parent_data.name = div_init->parent_name;
 	hw_init.parent_data = &parent_data;
 	hw_init.num_parents = 1;
 
diff --git a/drivers/clk/baikal-t1/ccu-div.h b/drivers/clk/baikal-t1/ccu-div.h
index 795665caefbd..b6a9c8e45318 100644
--- a/drivers/clk/baikal-t1/ccu-div.h
+++ b/drivers/clk/baikal-t1/ccu-div.h
@@ -13,6 +13,12 @@
 #include <linux/bits.h>
 #include <linux/of.h>
 
+/*
+ * CCU Divider private clock IDs
+ * @CCU_SYS_XGMAC_CLK: CCU XGMAC internal clock
+ */
+#define CCU_SYS_XGMAC_CLK		-2
+
 /*
  * CCU Divider private flags
  * @CCU_DIV_SKIP_ONE: Due to some reason divider can't be set to 1.
diff --git a/drivers/clk/baikal-t1/clk-ccu-div.c b/drivers/clk/baikal-t1/clk-ccu-div.c
index ea77eec40ddd..3953ae5664be 100644
--- a/drivers/clk/baikal-t1/clk-ccu-div.c
+++ b/drivers/clk/baikal-t1/clk-ccu-div.c
@@ -204,10 +204,12 @@ static const struct ccu_div_info sys_info[] = {
 			  "eth_clk", CCU_SYS_GMAC1_BASE, 5),
 	CCU_DIV_FIXED_INFO(CCU_SYS_GMAC1_PTP_CLK, "sys_gmac1_ptp_clk",
 			   "eth_clk", 10),
-	CCU_DIV_GATE_INFO(CCU_SYS_XGMAC_REF_CLK, "sys_xgmac_ref_clk",
-			  "eth_clk", CCU_SYS_XGMAC_BASE, 8),
+	CCU_DIV_GATE_INFO(CCU_SYS_XGMAC_CLK, "sys_xgmac_clk",
+			  "eth_clk", CCU_SYS_XGMAC_BASE, 1),
+	CCU_DIV_FIXED_INFO(CCU_SYS_XGMAC_REF_CLK, "sys_xgmac_ref_clk",
+			   "sys_xgmac_clk", 8),
 	CCU_DIV_FIXED_INFO(CCU_SYS_XGMAC_PTP_CLK, "sys_xgmac_ptp_clk",
-			   "eth_clk", 8),
+			   "sys_xgmac_clk", 8),
 	CCU_DIV_GATE_INFO(CCU_SYS_USB_CLK, "sys_usb_clk",
 			  "eth_clk", CCU_SYS_USB_BASE, 10),
 	CCU_DIV_VAR_INFO(CCU_SYS_PVT_CLK, "sys_pvt_clk",
-- 
2.35.1

[PATCH v8 4/7] clk: baikal-t1: Add SATA internal ref clock buffer

[Serge Semin]

It turns out the internal SATA reference clock signal will stay
unavailable for the SATA interface consumer until the buffer on it's way
is ungated. So aside with having the actual clock divider enabled we need
to ungate a buffer placed on the signal way to the SATA controller (most
likely some rudiment from the initial SoC release). Seeing the switch flag
is placed in the same register as the SATA-ref clock divider at a
non-standard ffset, let's implement it as a separate clock controller with
the set-rate propagation to the parental clock divider wrapper. As such
we'll be able to disable/enable and still change the original clock source
rate.

Fixes: 353afa3a8d2e ("clk: Add Baikal-T1 CCU Dividers driver")
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>

---

Changelog v4:
- This is a new patch created on v4 lap of the series.
---
 drivers/clk/baikal-t1/ccu-div.c     | 64 +++++++++++++++++++++++++++++
 drivers/clk/baikal-t1/ccu-div.h     |  4 ++
 drivers/clk/baikal-t1/clk-ccu-div.c | 18 +++++++-
 3 files changed, 85 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/baikal-t1/ccu-div.c b/drivers/clk/baikal-t1/ccu-div.c
index bbfa3526ee10..a6642f3d33d4 100644
--- a/drivers/clk/baikal-t1/ccu-div.c
+++ b/drivers/clk/baikal-t1/ccu-div.c
@@ -34,6 +34,7 @@
 #define CCU_DIV_CTL_CLKDIV_MASK(_width) \
 	GENMASK((_width) + CCU_DIV_CTL_CLKDIV_FLD - 1, CCU_DIV_CTL_CLKDIV_FLD)
 #define CCU_DIV_CTL_LOCK_SHIFTED	BIT(27)
+#define CCU_DIV_CTL_GATE_REF_BUF	BIT(28)
 #define CCU_DIV_CTL_LOCK_NORMAL		BIT(31)
 
 #define CCU_DIV_RST_DELAY_US		1
@@ -170,6 +171,40 @@ static int ccu_div_gate_is_enabled(struct clk_hw *hw)
 	return !!(val & CCU_DIV_CTL_EN);
 }
 
+static int ccu_div_buf_enable(struct clk_hw *hw)
+{
+	struct ccu_div *div = to_ccu_div(hw);
+	unsigned long flags;
+
+	spin_lock_irqsave(&div->lock, flags);
+	regmap_update_bits(div->sys_regs, div->reg_ctl,
+			   CCU_DIV_CTL_GATE_REF_BUF, 0);
+	spin_unlock_irqrestore(&div->lock, flags);
+
+	return 0;
+}
+
+static void ccu_div_buf_disable(struct clk_hw *hw)
+{
+	struct ccu_div *div = to_ccu_div(hw);
+	unsigned long flags;
+
+	spin_lock_irqsave(&div->lock, flags);
+	regmap_update_bits(div->sys_regs, div->reg_ctl,
+			   CCU_DIV_CTL_GATE_REF_BUF, CCU_DIV_CTL_GATE_REF_BUF);
+	spin_unlock_irqrestore(&div->lock, flags);
+}
+
+static int ccu_div_buf_is_enabled(struct clk_hw *hw)
+{
+	struct ccu_div *div = to_ccu_div(hw);
+	u32 val = 0;
+
+	regmap_read(div->sys_regs, div->reg_ctl, &val);
+
+	return !(val & CCU_DIV_CTL_GATE_REF_BUF);
+}
+
 static unsigned long ccu_div_var_recalc_rate(struct clk_hw *hw,
 					     unsigned long parent_rate)
 {
@@ -323,6 +358,7 @@ static const struct ccu_div_dbgfs_bit ccu_div_bits[] = {
 	CCU_DIV_DBGFS_BIT_ATTR("div_en", CCU_DIV_CTL_EN),
 	CCU_DIV_DBGFS_BIT_ATTR("div_rst", CCU_DIV_CTL_RST),
 	CCU_DIV_DBGFS_BIT_ATTR("div_bypass", CCU_DIV_CTL_SET_CLKDIV),
+	CCU_DIV_DBGFS_BIT_ATTR("div_buf", CCU_DIV_CTL_GATE_REF_BUF),
 	CCU_DIV_DBGFS_BIT_ATTR("div_lock", CCU_DIV_CTL_LOCK_NORMAL)
 };
 
@@ -441,6 +477,9 @@ static void ccu_div_var_debug_init(struct clk_hw *hw, struct dentry *dentry)
 			continue;
 		}
 
+		if (!strcmp("div_buf", name))
+			continue;
+
 		bits[didx] = ccu_div_bits[bidx];
 		bits[didx].div = div;
 
@@ -477,6 +516,21 @@ static void ccu_div_gate_debug_init(struct clk_hw *hw, struct dentry *dentry)
 				   &ccu_div_dbgfs_fixed_clkdiv_fops);
 }
 
+static void ccu_div_buf_debug_init(struct clk_hw *hw, struct dentry *dentry)
+{
+	struct ccu_div *div = to_ccu_div(hw);
+	struct ccu_div_dbgfs_bit *bit;
+
+	bit = kmalloc(sizeof(*bit), GFP_KERNEL);
+	if (!bit)
+		return;
+
+	*bit = ccu_div_bits[3];
+	bit->div = div;
+	debugfs_create_file_unsafe(bit->name, ccu_div_dbgfs_mode, dentry, bit,
+				   &ccu_div_dbgfs_bit_fops);
+}
+
 static void ccu_div_fixed_debug_init(struct clk_hw *hw, struct dentry *dentry)
 {
 	struct ccu_div *div = to_ccu_div(hw);
@@ -489,6 +543,7 @@ static void ccu_div_fixed_debug_init(struct clk_hw *hw, struct dentry *dentry)
 
 #define ccu_div_var_debug_init NULL
 #define ccu_div_gate_debug_init NULL
+#define ccu_div_buf_debug_init NULL
 #define ccu_div_fixed_debug_init NULL
 
 #endif /* !CONFIG_DEBUG_FS */
@@ -520,6 +575,13 @@ static const struct clk_ops ccu_div_gate_ops = {
 	.debug_init = ccu_div_gate_debug_init
 };
 
+static const struct clk_ops ccu_div_buf_ops = {
+	.enable = ccu_div_buf_enable,
+	.disable = ccu_div_buf_disable,
+	.is_enabled = ccu_div_buf_is_enabled,
+	.debug_init = ccu_div_buf_debug_init
+};
+
 static const struct clk_ops ccu_div_fixed_ops = {
 	.recalc_rate = ccu_div_fixed_recalc_rate,
 	.round_rate = ccu_div_fixed_round_rate,
@@ -566,6 +628,8 @@ struct ccu_div *ccu_div_hw_register(const struct ccu_div_init_data *div_init)
 	} else if (div_init->type == CCU_DIV_GATE) {
 		hw_init.ops = &ccu_div_gate_ops;
 		div->divider = div_init->divider;
+	} else if (div_init->type == CCU_DIV_BUF) {
+		hw_init.ops = &ccu_div_buf_ops;
 	} else if (div_init->type == CCU_DIV_FIXED) {
 		hw_init.ops = &ccu_div_fixed_ops;
 		div->divider = div_init->divider;
diff --git a/drivers/clk/baikal-t1/ccu-div.h b/drivers/clk/baikal-t1/ccu-div.h
index b6a9c8e45318..4eb49ff4803c 100644
--- a/drivers/clk/baikal-t1/ccu-div.h
+++ b/drivers/clk/baikal-t1/ccu-div.h
@@ -15,8 +15,10 @@
 
 /*
  * CCU Divider private clock IDs
+ * @CCU_SYS_SATA_CLK: CCU SATA internal clock
  * @CCU_SYS_XGMAC_CLK: CCU XGMAC internal clock
  */
+#define CCU_SYS_SATA_CLK		-1
 #define CCU_SYS_XGMAC_CLK		-2
 
 /*
@@ -37,11 +39,13 @@
  * enum ccu_div_type - CCU Divider types
  * @CCU_DIV_VAR: Clocks gate with variable divider.
  * @CCU_DIV_GATE: Clocks gate with fixed divider.
+ * @CCU_DIV_BUF: Clock gate with no divider.
  * @CCU_DIV_FIXED: Ungateable clock with fixed divider.
  */
 enum ccu_div_type {
 	CCU_DIV_VAR,
 	CCU_DIV_GATE,
+	CCU_DIV_BUF,
 	CCU_DIV_FIXED
 };
 
diff --git a/drivers/clk/baikal-t1/clk-ccu-div.c b/drivers/clk/baikal-t1/clk-ccu-div.c
index 3953ae5664be..90f4fda406ee 100644
--- a/drivers/clk/baikal-t1/clk-ccu-div.c
+++ b/drivers/clk/baikal-t1/clk-ccu-div.c
@@ -76,6 +76,16 @@
 		.divider = _divider				\
 	}
 
+#define CCU_DIV_BUF_INFO(_id, _name, _pname, _base, _flags)	\
+	{							\
+		.id = _id,					\
+		.name = _name,					\
+		.parent_name = _pname,				\
+		.base = _base,					\
+		.type = CCU_DIV_BUF,				\
+		.flags = _flags					\
+	}
+
 #define CCU_DIV_FIXED_INFO(_id, _name, _pname, _divider)	\
 	{							\
 		.id = _id,					\
@@ -188,11 +198,14 @@ static const struct ccu_div_rst_map axi_rst_map[] = {
  * for the SoC devices registers IO-operations.
  */
 static const struct ccu_div_info sys_info[] = {
-	CCU_DIV_VAR_INFO(CCU_SYS_SATA_REF_CLK, "sys_sata_ref_clk",
+	CCU_DIV_VAR_INFO(CCU_SYS_SATA_CLK, "sys_sata_clk",
 			 "sata_clk", CCU_SYS_SATA_REF_BASE, 4,
 			 CLK_SET_RATE_GATE,
 			 CCU_DIV_SKIP_ONE | CCU_DIV_LOCK_SHIFTED |
 			 CCU_DIV_RESET_DOMAIN),
+	CCU_DIV_BUF_INFO(CCU_SYS_SATA_REF_CLK, "sys_sata_ref_clk",
+			 "sys_sata_clk", CCU_SYS_SATA_REF_BASE,
+			 CLK_SET_RATE_PARENT),
 	CCU_DIV_VAR_INFO(CCU_SYS_APB_CLK, "sys_apb_clk",
 			 "pcie_clk", CCU_SYS_APB_BASE, 5,
 			 CLK_IS_CRITICAL, CCU_DIV_RESET_DOMAIN),
@@ -398,6 +411,9 @@ static int ccu_div_clk_register(struct ccu_div_data *data)
 			init.base = info->base;
 			init.sys_regs = data->sys_regs;
 			init.divider = info->divider;
+		} else if (init.type == CCU_DIV_BUF) {
+			init.base = info->base;
+			init.sys_regs = data->sys_regs;
 		} else {
 			init.divider = info->divider;
 		}
-- 
2.35.1

[PATCH v8 5/7] clk: baikal-t1: Move reset-controls code into a dedicated module

[Serge Semin]

Before adding the directly controlled resets support it's reasonable to
move the existing resets control functionality into a dedicated object for
the sake of the CCU dividers clock driver simplification. After the new
functionality was added clk-ccu-div.c would have got to a mixture of the
weakly dependent clocks and resets methods. Splitting the methods up into
the two objects will make the code easier to read and maintain. It shall
also improve the code scalability (though hopefully we won't need this
part that much in the future).

The reset control functionality is now implemented in the framework of a
single unit since splitting it up doesn't make much sense due to
relatively simple reset operations. The ccu-rst.c has been designed to be
looking like ccu-div.c or ccu-pll.c with two globally available methods
for the sake of the code unification and better code readability.

This commit doesn't provide any change in the CCU reset implementation
semantics. As before the driver will support the trigger-like CCU resets
only, which are responsible for the AXI-bus, APB-bus and SATA-ref blocks
reset. The assert/de-assert-capable reset controls support will be added
in the next commit.

Note the CCU Clock dividers and resets functionality split up was possible
due to not having any side-effects (at least we didn't found ones) of the
regmap-based concurrent access of the common CCU dividers/reset CSRs.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>

---

Changelog v4:
- Completely split CCU Dividers and Resets functionality. (@Stephen)

Changelog v6:
- Combine the reset-related code into a single file. (@Philipp)
- Refactor the code to support the linear reset IDs only. (@Philipp)
- Drop CCU_DIV_RST_MAP() macro. It's no longer used.

Changelog v7:
- Fix "Alignment should match open parenthesis" warning for the
  pr_err() method invocations. (@Philipp)

Changelog v8:
- Fix "sef-deasserted" spelling in the CLK_BT1_CCU_RST config help
  text. (@Randy)
---
 drivers/clk/baikal-t1/Kconfig       |  12 ++-
 drivers/clk/baikal-t1/Makefile      |   1 +
 drivers/clk/baikal-t1/ccu-div.c     |  19 ----
 drivers/clk/baikal-t1/ccu-div.h     |   4 +-
 drivers/clk/baikal-t1/ccu-rst.c     | 151 ++++++++++++++++++++++++++++
 drivers/clk/baikal-t1/ccu-rst.h     |  57 +++++++++++
 drivers/clk/baikal-t1/clk-ccu-div.c |  92 ++---------------
 7 files changed, 231 insertions(+), 105 deletions(-)
 create mode 100644 drivers/clk/baikal-t1/ccu-rst.c
 create mode 100644 drivers/clk/baikal-t1/ccu-rst.h

diff --git a/drivers/clk/baikal-t1/Kconfig b/drivers/clk/baikal-t1/Kconfig
index 03102f1094bc..f0b186830324 100644
--- a/drivers/clk/baikal-t1/Kconfig
+++ b/drivers/clk/baikal-t1/Kconfig
@@ -29,7 +29,6 @@ config CLK_BT1_CCU_PLL
 
 config CLK_BT1_CCU_DIV
 	bool "Baikal-T1 CCU Dividers support"
-	select RESET_CONTROLLER
 	select MFD_SYSCON
 	default MIPS_BAIKAL_T1
 	help
@@ -39,4 +38,15 @@ config CLK_BT1_CCU_DIV
 	  either gateable or ungateable. Some of the CCU dividers can be as well
 	  used to reset the domains they're supplying clock to.
 
+config CLK_BT1_CCU_RST
+	bool "Baikal-T1 CCU Resets support"
+	select RESET_CONTROLLER
+	select MFD_SYSCON
+	default MIPS_BAIKAL_T1
+	help
+	  Enable this to support the CCU reset blocks responsible for the
+	  AXI-bus and some subsystems reset. These are mainly the
+	  self-deasserted reset controls but there are several lines which
+	  can be directly asserted/de-asserted (PCIe and DDR sub-domains).
+
 endif
diff --git a/drivers/clk/baikal-t1/Makefile b/drivers/clk/baikal-t1/Makefile
index b3b9590b95ed..9c3637de9407 100644
--- a/drivers/clk/baikal-t1/Makefile
+++ b/drivers/clk/baikal-t1/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_CLK_BT1_CCU_PLL) += ccu-pll.o clk-ccu-pll.o
 obj-$(CONFIG_CLK_BT1_CCU_DIV) += ccu-div.o clk-ccu-div.o
+obj-$(CONFIG_CLK_BT1_CCU_RST) += ccu-rst.o
diff --git a/drivers/clk/baikal-t1/ccu-div.c b/drivers/clk/baikal-t1/ccu-div.c
index a6642f3d33d4..8d5fc7158f33 100644
--- a/drivers/clk/baikal-t1/ccu-div.c
+++ b/drivers/clk/baikal-t1/ccu-div.c
@@ -37,7 +37,6 @@
 #define CCU_DIV_CTL_GATE_REF_BUF	BIT(28)
 #define CCU_DIV_CTL_LOCK_NORMAL		BIT(31)
 
-#define CCU_DIV_RST_DELAY_US		1
 #define CCU_DIV_LOCK_CHECK_RETRIES	50
 
 #define CCU_DIV_CLKDIV_MIN		0
@@ -323,24 +322,6 @@ static int ccu_div_fixed_set_rate(struct clk_hw *hw, unsigned long rate,
 	return 0;
 }
 
-int ccu_div_reset_domain(struct ccu_div *div)
-{
-	unsigned long flags;
-
-	if (!div || !(div->features & CCU_DIV_RESET_DOMAIN))
-		return -EINVAL;
-
-	spin_lock_irqsave(&div->lock, flags);
-	regmap_update_bits(div->sys_regs, div->reg_ctl,
-			   CCU_DIV_CTL_RST, CCU_DIV_CTL_RST);
-	spin_unlock_irqrestore(&div->lock, flags);
-
-	/* The next delay must be enough to cover all the resets. */
-	udelay(CCU_DIV_RST_DELAY_US);
-
-	return 0;
-}
-
 #ifdef CONFIG_DEBUG_FS
 
 struct ccu_div_dbgfs_bit {
diff --git a/drivers/clk/baikal-t1/ccu-div.h b/drivers/clk/baikal-t1/ccu-div.h
index 4eb49ff4803c..ff97bb30fcc3 100644
--- a/drivers/clk/baikal-t1/ccu-div.h
+++ b/drivers/clk/baikal-t1/ccu-div.h
@@ -28,7 +28,7 @@
  * @CCU_DIV_SKIP_ONE_TO_THREE: For some reason divider can't be within [1,3].
  *			       It can be either 0 or greater than 3.
  * @CCU_DIV_LOCK_SHIFTED: Find lock-bit at non-standard position.
- * @CCU_DIV_RESET_DOMAIN: Provide reset clock domain method.
+ * @CCU_DIV_RESET_DOMAIN: There is a clock domain reset handle.
  */
 #define CCU_DIV_SKIP_ONE		BIT(1)
 #define CCU_DIV_SKIP_ONE_TO_THREE	BIT(2)
@@ -115,6 +115,4 @@ struct ccu_div *ccu_div_hw_register(const struct ccu_div_init_data *init);
 
 void ccu_div_hw_unregister(struct ccu_div *div);
 
-int ccu_div_reset_domain(struct ccu_div *div);
-
 #endif /* __CLK_BT1_CCU_DIV_H__ */
diff --git a/drivers/clk/baikal-t1/ccu-rst.c b/drivers/clk/baikal-t1/ccu-rst.c
new file mode 100644
index 000000000000..7db52633270f
--- /dev/null
+++ b/drivers/clk/baikal-t1/ccu-rst.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021 BAIKAL ELECTRONICS, JSC
+ *
+ * Authors:
+ *   Serge Semin <Sergey.Semin@baikalelectronics.ru>
+ *
+ * Baikal-T1 CCU Resets interface driver
+ */
+
+#define pr_fmt(fmt) "bt1-ccu-rst: " fmt
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/printk.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/reset/bt1-ccu.h>
+
+#include "ccu-rst.h"
+
+#define CCU_AXI_MAIN_BASE		0x030
+#define CCU_AXI_DDR_BASE		0x034
+#define CCU_AXI_SATA_BASE		0x038
+#define CCU_AXI_GMAC0_BASE		0x03C
+#define CCU_AXI_GMAC1_BASE		0x040
+#define CCU_AXI_XGMAC_BASE		0x044
+#define CCU_AXI_PCIE_M_BASE		0x048
+#define CCU_AXI_PCIE_S_BASE		0x04C
+#define CCU_AXI_USB_BASE		0x050
+#define CCU_AXI_HWA_BASE		0x054
+#define CCU_AXI_SRAM_BASE		0x058
+
+#define CCU_SYS_SATA_REF_BASE		0x060
+#define CCU_SYS_APB_BASE		0x064
+
+#define CCU_RST_DELAY_US		1
+
+#define CCU_RST_TRIG(_base, _ofs)		\
+	{					\
+		.base = _base,			\
+		.mask = BIT(_ofs),		\
+	}
+
+struct ccu_rst_info {
+	unsigned int base;
+	unsigned int mask;
+};
+
+/*
+ * Each AXI-bus clock divider is equipped with the corresponding clock-consumer
+ * domain reset (it's self-deasserted reset control).
+ */
+static const struct ccu_rst_info axi_rst_info[] = {
+	[CCU_AXI_MAIN_RST] = CCU_RST_TRIG(CCU_AXI_MAIN_BASE, 1),
+	[CCU_AXI_DDR_RST] = CCU_RST_TRIG(CCU_AXI_DDR_BASE, 1),
+	[CCU_AXI_SATA_RST] = CCU_RST_TRIG(CCU_AXI_SATA_BASE, 1),
+	[CCU_AXI_GMAC0_RST] = CCU_RST_TRIG(CCU_AXI_GMAC0_BASE, 1),
+	[CCU_AXI_GMAC1_RST] = CCU_RST_TRIG(CCU_AXI_GMAC1_BASE, 1),
+	[CCU_AXI_XGMAC_RST] = CCU_RST_TRIG(CCU_AXI_XGMAC_BASE, 1),
+	[CCU_AXI_PCIE_M_RST] = CCU_RST_TRIG(CCU_AXI_PCIE_M_BASE, 1),
+	[CCU_AXI_PCIE_S_RST] = CCU_RST_TRIG(CCU_AXI_PCIE_S_BASE, 1),
+	[CCU_AXI_USB_RST] = CCU_RST_TRIG(CCU_AXI_USB_BASE, 1),
+	[CCU_AXI_HWA_RST] = CCU_RST_TRIG(CCU_AXI_HWA_BASE, 1),
+	[CCU_AXI_SRAM_RST] = CCU_RST_TRIG(CCU_AXI_SRAM_BASE, 1),
+};
+
+/*
+ * SATA reference clock domain and APB-bus domain are connected with the
+ * sefl-deasserted reset control, which can be activated via the corresponding
+ * clock divider register. DDR and PCIe sub-domains can be reset with directly
+ * controlled reset signals. Resetting the DDR controller though won't end up
+ * well while the Linux kernel is working.
+ */
+static const struct ccu_rst_info sys_rst_info[] = {
+	[CCU_SYS_SATA_REF_RST] = CCU_RST_TRIG(CCU_SYS_SATA_REF_BASE, 1),
+	[CCU_SYS_APB_RST] = CCU_RST_TRIG(CCU_SYS_APB_BASE, 1),
+};
+
+static int ccu_rst_reset(struct reset_controller_dev *rcdev, unsigned long idx)
+{
+	struct ccu_rst *rst = to_ccu_rst(rcdev);
+	const struct ccu_rst_info *info = &rst->rsts_info[idx];
+
+	regmap_update_bits(rst->sys_regs, info->base, info->mask, info->mask);
+
+	/* The next delay must be enough to cover all the resets. */
+	udelay(CCU_RST_DELAY_US);
+
+	return 0;
+}
+
+static const struct reset_control_ops ccu_rst_ops = {
+	.reset = ccu_rst_reset,
+};
+
+struct ccu_rst *ccu_rst_hw_register(const struct ccu_rst_init_data *rst_init)
+{
+	struct ccu_rst *rst;
+	int ret;
+
+	if (!rst_init)
+		return ERR_PTR(-EINVAL);
+
+	rst = kzalloc(sizeof(*rst), GFP_KERNEL);
+	if (!rst)
+		return ERR_PTR(-ENOMEM);
+
+	rst->sys_regs = rst_init->sys_regs;
+	if (of_device_is_compatible(rst_init->np, "baikal,bt1-ccu-axi")) {
+		rst->rcdev.nr_resets = ARRAY_SIZE(axi_rst_info);
+		rst->rsts_info = axi_rst_info;
+	} else if (of_device_is_compatible(rst_init->np, "baikal,bt1-ccu-sys")) {
+		rst->rcdev.nr_resets = ARRAY_SIZE(sys_rst_info);
+		rst->rsts_info = sys_rst_info;
+	} else {
+		pr_err("Incompatible DT node '%s' specified\n",
+		       of_node_full_name(rst_init->np));
+		ret = -EINVAL;
+		goto err_kfree_rst;
+	}
+
+	rst->rcdev.owner = THIS_MODULE;
+	rst->rcdev.ops = &ccu_rst_ops;
+	rst->rcdev.of_node = rst_init->np;
+
+	ret = reset_controller_register(&rst->rcdev);
+	if (ret) {
+		pr_err("Couldn't register '%s' reset controller\n",
+		       of_node_full_name(rst_init->np));
+		goto err_kfree_rst;
+	}
+
+	return rst;
+
+err_kfree_rst:
+	kfree(rst);
+
+	return ERR_PTR(ret);
+}
+
+void ccu_rst_hw_unregister(struct ccu_rst *rst)
+{
+	reset_controller_unregister(&rst->rcdev);
+
+	kfree(rst);
+}
diff --git a/drivers/clk/baikal-t1/ccu-rst.h b/drivers/clk/baikal-t1/ccu-rst.h
new file mode 100644
index 000000000000..68214d777465
--- /dev/null
+++ b/drivers/clk/baikal-t1/ccu-rst.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 BAIKAL ELECTRONICS, JSC
+ *
+ * Baikal-T1 CCU Resets interface driver
+ */
+#ifndef __CLK_BT1_CCU_RST_H__
+#define __CLK_BT1_CCU_RST_H__
+
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+struct ccu_rst_info;
+
+/*
+ * struct ccu_rst_init_data - CCU Resets initialization data
+ * @sys_regs: Baikal-T1 System Controller registers map.
+ * @np: Pointer to the node with the System CCU block.
+ */
+struct ccu_rst_init_data {
+	struct regmap *sys_regs;
+	struct device_node *np;
+};
+
+/*
+ * struct ccu_rst - CCU Reset descriptor
+ * @rcdev: Reset controller descriptor.
+ * @sys_regs: Baikal-T1 System Controller registers map.
+ * @rsts_info: Reset flag info (base address and mask).
+ */
+struct ccu_rst {
+	struct reset_controller_dev rcdev;
+	struct regmap *sys_regs;
+	const struct ccu_rst_info *rsts_info;
+};
+#define to_ccu_rst(_rcdev) container_of(_rcdev, struct ccu_rst, rcdev)
+
+#ifdef CONFIG_CLK_BT1_CCU_RST
+
+struct ccu_rst *ccu_rst_hw_register(const struct ccu_rst_init_data *init);
+
+void ccu_rst_hw_unregister(struct ccu_rst *rst);
+
+#else
+
+static inline
+struct ccu_rst *ccu_rst_hw_register(const struct ccu_rst_init_data *init)
+{
+	return NULL;
+}
+
+static inline void ccu_rst_hw_unregister(struct ccu_rst *rst) {}
+
+#endif
+
+#endif /* __CLK_BT1_CCU_RST_H__ */
diff --git a/drivers/clk/baikal-t1/clk-ccu-div.c b/drivers/clk/baikal-t1/clk-ccu-div.c
index 90f4fda406ee..278aa38d767e 100644
--- a/drivers/clk/baikal-t1/clk-ccu-div.c
+++ b/drivers/clk/baikal-t1/clk-ccu-div.c
@@ -24,9 +24,9 @@
 #include <linux/regmap.h>
 
 #include <dt-bindings/clock/bt1-ccu.h>
-#include <dt-bindings/reset/bt1-ccu.h>
 
 #include "ccu-div.h"
+#include "ccu-rst.h"
 
 #define CCU_AXI_MAIN_BASE		0x030
 #define CCU_AXI_DDR_BASE		0x034
@@ -95,12 +95,6 @@
 		.divider = _divider				\
 	}
 
-#define CCU_DIV_RST_MAP(_rst_id, _clk_id)	\
-	{					\
-		.rst_id = _rst_id,		\
-		.clk_id = _clk_id		\
-	}
-
 struct ccu_div_info {
 	unsigned int id;
 	const char *name;
@@ -115,11 +109,6 @@ struct ccu_div_info {
 	unsigned long features;
 };
 
-struct ccu_div_rst_map {
-	unsigned int rst_id;
-	unsigned int clk_id;
-};
-
 struct ccu_div_data {
 	struct device_node *np;
 	struct regmap *sys_regs;
@@ -128,11 +117,8 @@ struct ccu_div_data {
 	const struct ccu_div_info *divs_info;
 	struct ccu_div **divs;
 
-	unsigned int rst_num;
-	const struct ccu_div_rst_map *rst_map;
-	struct reset_controller_dev rcdev;
+	struct ccu_rst *rsts;
 };
-#define to_ccu_div_data(_rcdev) container_of(_rcdev, struct ccu_div_data, rcdev)
 
 /*
  * AXI Main Interconnect (axi_main_clk) and DDR AXI-bus (axi_ddr_clk) clocks
@@ -179,20 +165,6 @@ static const struct ccu_div_info axi_info[] = {
 			 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN)
 };
 
-static const struct ccu_div_rst_map axi_rst_map[] = {
-	CCU_DIV_RST_MAP(CCU_AXI_MAIN_RST, CCU_AXI_MAIN_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_DDR_RST, CCU_AXI_DDR_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_SATA_RST, CCU_AXI_SATA_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_GMAC0_RST, CCU_AXI_GMAC0_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_GMAC1_RST, CCU_AXI_GMAC1_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_XGMAC_RST, CCU_AXI_XGMAC_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_PCIE_M_RST, CCU_AXI_PCIE_M_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_PCIE_S_RST, CCU_AXI_PCIE_S_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_USB_RST, CCU_AXI_USB_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_HWA_RST, CCU_AXI_HWA_CLK),
-	CCU_DIV_RST_MAP(CCU_AXI_SRAM_RST, CCU_AXI_SRAM_CLK)
-};
-
 /*
  * APB-bus clock is marked as critical since it's a main communication bus
  * for the SoC devices registers IO-operations.
@@ -254,11 +226,6 @@ static const struct ccu_div_info sys_info[] = {
 			 CLK_SET_RATE_GATE, CCU_DIV_SKIP_ONE_TO_THREE)
 };
 
-static const struct ccu_div_rst_map sys_rst_map[] = {
-	CCU_DIV_RST_MAP(CCU_SYS_SATA_REF_RST, CCU_SYS_SATA_REF_CLK),
-	CCU_DIV_RST_MAP(CCU_SYS_APB_RST, CCU_SYS_APB_CLK),
-};
-
 static struct ccu_div *ccu_div_find_desc(struct ccu_div_data *data,
 					 unsigned int clk_id)
 {
@@ -274,42 +241,6 @@ static struct ccu_div *ccu_div_find_desc(struct ccu_div_data *data,
 	return ERR_PTR(-EINVAL);
 }
 
-static int ccu_div_reset(struct reset_controller_dev *rcdev,
-			 unsigned long rst_id)
-{
-	struct ccu_div_data *data = to_ccu_div_data(rcdev);
-	const struct ccu_div_rst_map *map;
-	struct ccu_div *div;
-	int idx, ret;
-
-	for (idx = 0, map = data->rst_map; idx < data->rst_num; ++idx, ++map) {
-		if (map->rst_id == rst_id)
-			break;
-	}
-	if (idx == data->rst_num) {
-		pr_err("Invalid reset ID %lu specified\n", rst_id);
-		return -EINVAL;
-	}
-
-	div = ccu_div_find_desc(data, map->clk_id);
-	if (IS_ERR(div)) {
-		pr_err("Invalid clock ID %d in mapping\n", map->clk_id);
-		return PTR_ERR(div);
-	}
-
-	ret = ccu_div_reset_domain(div);
-	if (ret) {
-		pr_err("Reset isn't supported by divider %s\n",
-			clk_hw_get_name(ccu_div_get_clk_hw(div)));
-	}
-
-	return ret;
-}
-
-static const struct reset_control_ops ccu_div_rst_ops = {
-	.reset = ccu_div_reset,
-};
-
 static struct ccu_div_data *ccu_div_create_data(struct device_node *np)
 {
 	struct ccu_div_data *data;
@@ -323,13 +254,9 @@ static struct ccu_div_data *ccu_div_create_data(struct device_node *np)
 	if (of_device_is_compatible(np, "baikal,bt1-ccu-axi")) {
 		data->divs_num = ARRAY_SIZE(axi_info);
 		data->divs_info = axi_info;
-		data->rst_num = ARRAY_SIZE(axi_rst_map);
-		data->rst_map = axi_rst_map;
 	} else if (of_device_is_compatible(np, "baikal,bt1-ccu-sys")) {
 		data->divs_num = ARRAY_SIZE(sys_info);
 		data->divs_info = sys_info;
-		data->rst_num = ARRAY_SIZE(sys_rst_map);
-		data->rst_map = sys_rst_map;
 	} else {
 		pr_err("Incompatible DT node '%s' specified\n",
 			of_node_full_name(np));
@@ -455,18 +382,19 @@ static void ccu_div_clk_unregister(struct ccu_div_data *data)
 
 static int ccu_div_rst_register(struct ccu_div_data *data)
 {
-	int ret;
+	struct ccu_rst_init_data init = {0};
 
-	data->rcdev.ops = &ccu_div_rst_ops;
-	data->rcdev.of_node = data->np;
-	data->rcdev.nr_resets = data->rst_num;
+	init.sys_regs = data->sys_regs;
+	init.np = data->np;
 
-	ret = reset_controller_register(&data->rcdev);
-	if (ret)
+	data->rsts = ccu_rst_hw_register(&init);
+	if (IS_ERR(data->rsts)) {
 		pr_err("Couldn't register divider '%s' reset controller\n",
 			of_node_full_name(data->np));
+		return PTR_ERR(data->rsts);
+	}
 
-	return ret;
+	return 0;
 }
 
 static void ccu_div_init(struct device_node *np)
-- 
2.35.1

[PATCH v8 6/7] clk: baikal-t1: Add DDR/PCIe directly controlled resets support

[Serge Semin]

Aside with a set of the trigger-like resets Baikal-T1 CCU provides two
additional blocks with directly controlled reset signals. In particular it
concerns DDR full and initial resets and various PCIe sub-domains resets.
Let's add the direct reset assertion/de-assertion of the corresponding
flags support into the Baikal-T1 CCU driver then. It will be required at
least for the PCIe platform driver. Obviously the DDR controller isn't
supposed to be fully reset in the kernel, so the corresponding controls
are added just for the sake of the interface implementation completeness.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>

---

Changelog v6:
- Refactor the code to support the linear reset IDs only. (@Philipp)

Changelog v7:
- Drop empty line from the sys_rst_info structure initialization block.
  (@Philipp)
---
 drivers/clk/baikal-t1/ccu-rst.c     | 66 +++++++++++++++++++++++++++++
 drivers/clk/baikal-t1/ccu-rst.h     | 10 +++++
 include/dt-bindings/reset/bt1-ccu.h |  9 ++++
 3 files changed, 85 insertions(+)

diff --git a/drivers/clk/baikal-t1/ccu-rst.c b/drivers/clk/baikal-t1/ccu-rst.c
index 7db52633270f..40023ea67463 100644
--- a/drivers/clk/baikal-t1/ccu-rst.c
+++ b/drivers/clk/baikal-t1/ccu-rst.c
@@ -35,18 +35,29 @@
 #define CCU_AXI_HWA_BASE		0x054
 #define CCU_AXI_SRAM_BASE		0x058
 
+#define CCU_SYS_DDR_BASE		0x02c
 #define CCU_SYS_SATA_REF_BASE		0x060
 #define CCU_SYS_APB_BASE		0x064
+#define CCU_SYS_PCIE_BASE		0x144
 
 #define CCU_RST_DELAY_US		1
 
 #define CCU_RST_TRIG(_base, _ofs)		\
 	{					\
+		.type = CCU_RST_TRIG,		\
+		.base = _base,			\
+		.mask = BIT(_ofs),		\
+	}
+
+#define CCU_RST_DIR(_base, _ofs)		\
+	{					\
+		.type = CCU_RST_DIR,		\
 		.base = _base,			\
 		.mask = BIT(_ofs),		\
 	}
 
 struct ccu_rst_info {
+	enum ccu_rst_type type;
 	unsigned int base;
 	unsigned int mask;
 };
@@ -79,6 +90,15 @@ static const struct ccu_rst_info axi_rst_info[] = {
 static const struct ccu_rst_info sys_rst_info[] = {
 	[CCU_SYS_SATA_REF_RST] = CCU_RST_TRIG(CCU_SYS_SATA_REF_BASE, 1),
 	[CCU_SYS_APB_RST] = CCU_RST_TRIG(CCU_SYS_APB_BASE, 1),
+	[CCU_SYS_DDR_FULL_RST] = CCU_RST_DIR(CCU_SYS_DDR_BASE, 1),
+	[CCU_SYS_DDR_INIT_RST] = CCU_RST_DIR(CCU_SYS_DDR_BASE, 2),
+	[CCU_SYS_PCIE_PCS_PHY_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 0),
+	[CCU_SYS_PCIE_PIPE0_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 4),
+	[CCU_SYS_PCIE_CORE_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 8),
+	[CCU_SYS_PCIE_PWR_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 9),
+	[CCU_SYS_PCIE_STICKY_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 10),
+	[CCU_SYS_PCIE_NSTICKY_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 11),
+	[CCU_SYS_PCIE_HOT_RST] = CCU_RST_DIR(CCU_SYS_PCIE_BASE, 12),
 };
 
 static int ccu_rst_reset(struct reset_controller_dev *rcdev, unsigned long idx)
@@ -86,6 +106,9 @@ static int ccu_rst_reset(struct reset_controller_dev *rcdev, unsigned long idx)
 	struct ccu_rst *rst = to_ccu_rst(rcdev);
 	const struct ccu_rst_info *info = &rst->rsts_info[idx];
 
+	if (info->type != CCU_RST_TRIG)
+		return -EOPNOTSUPP;
+
 	regmap_update_bits(rst->sys_regs, info->base, info->mask, info->mask);
 
 	/* The next delay must be enough to cover all the resets. */
@@ -94,8 +117,51 @@ static int ccu_rst_reset(struct reset_controller_dev *rcdev, unsigned long idx)
 	return 0;
 }
 
+static int ccu_rst_set(struct reset_controller_dev *rcdev,
+		       unsigned long idx, bool high)
+{
+	struct ccu_rst *rst = to_ccu_rst(rcdev);
+	const struct ccu_rst_info *info = &rst->rsts_info[idx];
+
+	if (info->type != CCU_RST_DIR)
+		return high ? -EOPNOTSUPP : 0;
+
+	return regmap_update_bits(rst->sys_regs, info->base,
+				  info->mask, high ? info->mask : 0);
+}
+
+static int ccu_rst_assert(struct reset_controller_dev *rcdev,
+			  unsigned long idx)
+{
+	return ccu_rst_set(rcdev, idx, true);
+}
+
+static int ccu_rst_deassert(struct reset_controller_dev *rcdev,
+			    unsigned long idx)
+{
+	return ccu_rst_set(rcdev, idx, false);
+}
+
+static int ccu_rst_status(struct reset_controller_dev *rcdev,
+			  unsigned long idx)
+{
+	struct ccu_rst *rst = to_ccu_rst(rcdev);
+	const struct ccu_rst_info *info = &rst->rsts_info[idx];
+	u32 val;
+
+	if (info->type != CCU_RST_DIR)
+		return -EOPNOTSUPP;
+
+	regmap_read(rst->sys_regs, info->base, &val);
+
+	return !!(val & info->mask);
+}
+
 static const struct reset_control_ops ccu_rst_ops = {
 	.reset = ccu_rst_reset,
+	.assert = ccu_rst_assert,
+	.deassert = ccu_rst_deassert,
+	.status = ccu_rst_status,
 };
 
 struct ccu_rst *ccu_rst_hw_register(const struct ccu_rst_init_data *rst_init)
diff --git a/drivers/clk/baikal-t1/ccu-rst.h b/drivers/clk/baikal-t1/ccu-rst.h
index 68214d777465..d6e8b2f671f4 100644
--- a/drivers/clk/baikal-t1/ccu-rst.h
+++ b/drivers/clk/baikal-t1/ccu-rst.h
@@ -13,6 +13,16 @@
 
 struct ccu_rst_info;
 
+/*
+ * enum ccu_rst_type - CCU Reset types
+ * @CCU_RST_TRIG: Self-deasserted reset signal.
+ * @CCU_RST_DIR: Directly controlled reset signal.
+ */
+enum ccu_rst_type {
+	CCU_RST_TRIG,
+	CCU_RST_DIR,
+};
+
 /*
  * struct ccu_rst_init_data - CCU Resets initialization data
  * @sys_regs: Baikal-T1 System Controller registers map.
diff --git a/include/dt-bindings/reset/bt1-ccu.h b/include/dt-bindings/reset/bt1-ccu.h
index 3578e83026bc..c691efaa678f 100644
--- a/include/dt-bindings/reset/bt1-ccu.h
+++ b/include/dt-bindings/reset/bt1-ccu.h
@@ -21,5 +21,14 @@
 
 #define CCU_SYS_SATA_REF_RST		0
 #define CCU_SYS_APB_RST			1
+#define CCU_SYS_DDR_FULL_RST		2
+#define CCU_SYS_DDR_INIT_RST		3
+#define CCU_SYS_PCIE_PCS_PHY_RST	4
+#define CCU_SYS_PCIE_PIPE0_RST		5
+#define CCU_SYS_PCIE_CORE_RST		6
+#define CCU_SYS_PCIE_PWR_RST		7
+#define CCU_SYS_PCIE_STICKY_RST		8
+#define CCU_SYS_PCIE_NSTICKY_RST	9
+#define CCU_SYS_PCIE_HOT_RST		10
 
 #endif /* __DT_BINDINGS_RESET_BT1_CCU_H */
-- 
2.35.1

[PATCH v8 7/7] clk: baikal-t1: Convert to platform device driver

[Serge Semin]

In accordance with the way the MIPS platform is normally design there are
only six clock sources which need to be available on the kernel start in
order to one end up booting correctly:
+ CPU PLL: needed by the r4k and MIPS GIC timer drivers. The former one is
  initialized by the arch code, while the later one is implemented in the
  mips-gic-timer.c driver as the OF-declared timer.
+ PCIe PLL: required as a parental clock source for the APB/timer domains.
+ APB clock: needed in order to access all the SoC CSRs at least for the
  timer OF-declared drivers.
+ APB Timer{0-2} clocks: these are the DW APB timers which drivers
  dw_apb_timer_of.c are implemented as the OF-declared timers.

So as long as the clocks above are available early the kernel will
normally work. Let's convert the Baikal-T1 CCU drivers to the platform
device drivers keeping that in mind.

Generally speaking the conversion isn't that complicated since the driver
infrastructure has been designed as flexible enough for that. First we
need to add a new PLL/Divider clock features flag which indicates the
corresponding clock source as a basic one and that clock sources will be
available on the kernel early boot stages. Second the internal PLL/Divider
descriptors need to be initialized with -EPROBE_DEFER value as the
corresponding clock source is unavailable at the early stages. They will
be allocated and initialized on the Baikal-T1 clock platform driver probe
procedure. Finally the already available PLL/Divider init functions need
to be split up into two ones: init procedure performed in the framework of
the OF-declared clock initialization (of_clk_init()), and the probe
procedure called by the platform devices bus driver. Note the later method
will just continue the system clocks initialization started in the former
one.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>

---

Changelog v4:
- This is a new patch created on v4 lap of the series to make @Stephen
  a bit more happy about this series.)

Changelog v7:
- Fix "Alignment should match open parenthesis" warning for the
  pr_err() method invocations. (@Philipp)
---
 drivers/clk/baikal-t1/ccu-div.h     |   3 +
 drivers/clk/baikal-t1/ccu-pll.h     |   8 ++
 drivers/clk/baikal-t1/clk-ccu-div.c | 149 +++++++++++++++++++++++-----
 drivers/clk/baikal-t1/clk-ccu-pll.c | 128 +++++++++++++++++++-----
 4 files changed, 235 insertions(+), 53 deletions(-)

diff --git a/drivers/clk/baikal-t1/ccu-div.h b/drivers/clk/baikal-t1/ccu-div.h
index ff97bb30fcc3..76d8ee44d415 100644
--- a/drivers/clk/baikal-t1/ccu-div.h
+++ b/drivers/clk/baikal-t1/ccu-div.h
@@ -23,6 +23,8 @@
 
 /*
  * CCU Divider private flags
+ * @CCU_DIV_BASIC: Basic divider clock required by the kernel as early as
+ *		   possible.
  * @CCU_DIV_SKIP_ONE: Due to some reason divider can't be set to 1.
  *		      It can be 0 though, which is functionally the same.
  * @CCU_DIV_SKIP_ONE_TO_THREE: For some reason divider can't be within [1,3].
@@ -30,6 +32,7 @@
  * @CCU_DIV_LOCK_SHIFTED: Find lock-bit at non-standard position.
  * @CCU_DIV_RESET_DOMAIN: There is a clock domain reset handle.
  */
+#define CCU_DIV_BASIC			BIT(0)
 #define CCU_DIV_SKIP_ONE		BIT(1)
 #define CCU_DIV_SKIP_ONE_TO_THREE	BIT(2)
 #define CCU_DIV_LOCK_SHIFTED		BIT(3)
diff --git a/drivers/clk/baikal-t1/ccu-pll.h b/drivers/clk/baikal-t1/ccu-pll.h
index 76cd9132a219..a71bfd7b90ec 100644
--- a/drivers/clk/baikal-t1/ccu-pll.h
+++ b/drivers/clk/baikal-t1/ccu-pll.h
@@ -13,6 +13,12 @@
 #include <linux/bits.h>
 #include <linux/of.h>
 
+/*
+ * CCU PLL private flags
+ * @CCU_PLL_BASIC: Basic PLL required by the kernel as early as possible.
+ */
+#define CCU_PLL_BASIC		BIT(0)
+
 /*
  * struct ccu_pll_init_data - CCU PLL initialization data
  * @id: Clock private identifier.
@@ -22,6 +28,7 @@
  * @sys_regs: Baikal-T1 System Controller registers map.
  * @np: Pointer to the node describing the CCU PLLs.
  * @flags: PLL clock flags.
+ * @features: PLL private features.
  */
 struct ccu_pll_init_data {
 	unsigned int id;
@@ -31,6 +38,7 @@ struct ccu_pll_init_data {
 	struct regmap *sys_regs;
 	struct device_node *np;
 	unsigned long flags;
+	unsigned long features;
 };
 
 /*
diff --git a/drivers/clk/baikal-t1/clk-ccu-div.c b/drivers/clk/baikal-t1/clk-ccu-div.c
index 278aa38d767e..b0577c5cf41c 100644
--- a/drivers/clk/baikal-t1/clk-ccu-div.c
+++ b/drivers/clk/baikal-t1/clk-ccu-div.c
@@ -12,6 +12,7 @@
 #define pr_fmt(fmt) "bt1-ccu-div: " fmt
 
 #include <linux/kernel.h>
+#include <linux/platform_device.h>
 #include <linux/printk.h>
 #include <linux/slab.h>
 #include <linux/clk-provider.h>
@@ -180,7 +181,7 @@ static const struct ccu_div_info sys_info[] = {
 			 CLK_SET_RATE_PARENT),
 	CCU_DIV_VAR_INFO(CCU_SYS_APB_CLK, "sys_apb_clk",
 			 "pcie_clk", CCU_SYS_APB_BASE, 5,
-			 CLK_IS_CRITICAL, CCU_DIV_RESET_DOMAIN),
+			 CLK_IS_CRITICAL, CCU_DIV_BASIC | CCU_DIV_RESET_DOMAIN),
 	CCU_DIV_GATE_INFO(CCU_SYS_GMAC0_TX_CLK, "sys_gmac0_tx_clk",
 			  "eth_clk", CCU_SYS_GMAC0_BASE, 5),
 	CCU_DIV_FIXED_INFO(CCU_SYS_GMAC0_PTP_CLK, "sys_gmac0_ptp_clk",
@@ -214,28 +215,53 @@ static const struct ccu_div_info sys_info[] = {
 			   "ref_clk", 25),
 	CCU_DIV_VAR_INFO(CCU_SYS_TIMER0_CLK, "sys_timer0_clk",
 			 "ref_clk", CCU_SYS_TIMER0_BASE, 17,
-			 CLK_SET_RATE_GATE, 0),
+			 CLK_SET_RATE_GATE, CCU_DIV_BASIC),
 	CCU_DIV_VAR_INFO(CCU_SYS_TIMER1_CLK, "sys_timer1_clk",
 			 "ref_clk", CCU_SYS_TIMER1_BASE, 17,
-			 CLK_SET_RATE_GATE, 0),
+			 CLK_SET_RATE_GATE, CCU_DIV_BASIC),
 	CCU_DIV_VAR_INFO(CCU_SYS_TIMER2_CLK, "sys_timer2_clk",
 			 "ref_clk", CCU_SYS_TIMER2_BASE, 17,
-			 CLK_SET_RATE_GATE, 0),
+			 CLK_SET_RATE_GATE, CCU_DIV_BASIC),
 	CCU_DIV_VAR_INFO(CCU_SYS_WDT_CLK, "sys_wdt_clk",
 			 "eth_clk", CCU_SYS_WDT_BASE, 17,
 			 CLK_SET_RATE_GATE, CCU_DIV_SKIP_ONE_TO_THREE)
 };
 
+static struct ccu_div_data *axi_data;
+static struct ccu_div_data *sys_data;
+
+static void ccu_div_set_data(struct ccu_div_data *data)
+{
+	struct device_node *np = data->np;
+
+	if (of_device_is_compatible(np, "baikal,bt1-ccu-axi"))
+		axi_data = data;
+	else if (of_device_is_compatible(np, "baikal,bt1-ccu-sys"))
+		sys_data = data;
+	else
+		pr_err("Invalid DT node '%s' specified\n", of_node_full_name(np));
+}
+
+static struct ccu_div_data *ccu_div_get_data(struct device_node *np)
+{
+	if (of_device_is_compatible(np, "baikal,bt1-ccu-axi"))
+		return axi_data;
+	else if (of_device_is_compatible(np, "baikal,bt1-ccu-sys"))
+		return sys_data;
+
+	pr_err("Invalid DT node '%s' specified\n", of_node_full_name(np));
+
+	return NULL;
+}
+
 static struct ccu_div *ccu_div_find_desc(struct ccu_div_data *data,
 					 unsigned int clk_id)
 {
-	struct ccu_div *div;
 	int idx;
 
 	for (idx = 0; idx < data->divs_num; ++idx) {
-		div = data->divs[idx];
-		if (div && div->id == clk_id)
-			return div;
+		if (data->divs_info[idx].id == clk_id)
+			return data->divs[idx];
 	}
 
 	return ERR_PTR(-EINVAL);
@@ -307,14 +333,16 @@ static struct clk_hw *ccu_div_of_clk_hw_get(struct of_phandle_args *clkspec,
 	clk_id = clkspec->args[0];
 	div = ccu_div_find_desc(data, clk_id);
 	if (IS_ERR(div)) {
-		pr_info("Invalid clock ID %d specified\n", clk_id);
+		if (div != ERR_PTR(-EPROBE_DEFER))
+			pr_info("Invalid clock ID %d specified\n", clk_id);
+
 		return ERR_CAST(div);
 	}
 
 	return ccu_div_get_clk_hw(div);
 }
 
-static int ccu_div_clk_register(struct ccu_div_data *data)
+static int ccu_div_clk_register(struct ccu_div_data *data, bool defer)
 {
 	int idx, ret;
 
@@ -322,6 +350,13 @@ static int ccu_div_clk_register(struct ccu_div_data *data)
 		const struct ccu_div_info *info = &data->divs_info[idx];
 		struct ccu_div_init_data init = {0};
 
+		if (!!(info->features & CCU_DIV_BASIC) ^ defer) {
+			if (!data->divs[idx])
+				data->divs[idx] = ERR_PTR(-EPROBE_DEFER);
+
+			continue;
+		}
+
 		init.id = info->id;
 		init.name = info->name;
 		init.parent_name = info->parent_name;
@@ -354,30 +389,43 @@ static int ccu_div_clk_register(struct ccu_div_data *data)
 		}
 	}
 
-	ret = of_clk_add_hw_provider(data->np, ccu_div_of_clk_hw_get, data);
-	if (ret) {
-		pr_err("Couldn't register dividers '%s' clock provider\n",
-			of_node_full_name(data->np));
-		goto err_hw_unregister;
-	}
-
 	return 0;
 
 err_hw_unregister:
-	for (--idx; idx >= 0; --idx)
+	for (--idx; idx >= 0; --idx) {
+		if (!!(data->divs_info[idx].features & CCU_DIV_BASIC) ^ defer)
+			continue;
+
 		ccu_div_hw_unregister(data->divs[idx]);
+	}
 
 	return ret;
 }
 
-static void ccu_div_clk_unregister(struct ccu_div_data *data)
+static void ccu_div_clk_unregister(struct ccu_div_data *data, bool defer)
 {
 	int idx;
 
-	of_clk_del_provider(data->np);
+	/* Uninstall only the clocks registered on the specfied stage */
+	for (idx = 0; idx < data->divs_num; ++idx) {
+		if (!!(data->divs_info[idx].features & CCU_DIV_BASIC) ^ defer)
+			continue;
 
-	for (idx = 0; idx < data->divs_num; ++idx)
 		ccu_div_hw_unregister(data->divs[idx]);
+	}
+}
+
+static int ccu_div_of_register(struct ccu_div_data *data)
+{
+	int ret;
+
+	ret = of_clk_add_hw_provider(data->np, ccu_div_of_clk_hw_get, data);
+	if (ret) {
+		pr_err("Couldn't register dividers '%s' clock provider\n",
+		       of_node_full_name(data->np));
+	}
+
+	return ret;
 }
 
 static int ccu_div_rst_register(struct ccu_div_data *data)
@@ -397,7 +445,49 @@ static int ccu_div_rst_register(struct ccu_div_data *data)
 	return 0;
 }
 
-static void ccu_div_init(struct device_node *np)
+static int ccu_div_probe(struct platform_device *pdev)
+{
+	struct ccu_div_data *data;
+	int ret;
+
+	data = ccu_div_get_data(dev_of_node(&pdev->dev));
+	if (!data)
+		return -EINVAL;
+
+	ret = ccu_div_clk_register(data, false);
+	if (ret)
+		return ret;
+
+	ret = ccu_div_rst_register(data);
+	if (ret)
+		goto err_clk_unregister;
+
+	return 0;
+
+err_clk_unregister:
+	ccu_div_clk_unregister(data, false);
+
+	return ret;
+}
+
+static const struct of_device_id ccu_div_of_match[] = {
+	{ .compatible = "baikal,bt1-ccu-axi" },
+	{ .compatible = "baikal,bt1-ccu-sys" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ccu_div_of_match);
+
+static struct platform_driver ccu_div_driver = {
+	.probe  = ccu_div_probe,
+	.driver = {
+		.name = "clk-ccu-div",
+		.of_match_table = ccu_div_of_match,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver(ccu_div_driver);
+
+static __init void ccu_div_init(struct device_node *np)
 {
 	struct ccu_div_data *data;
 	int ret;
@@ -410,22 +500,27 @@ static void ccu_div_init(struct device_node *np)
 	if (ret)
 		goto err_free_data;
 
-	ret = ccu_div_clk_register(data);
+	ret = ccu_div_clk_register(data, true);
 	if (ret)
 		goto err_free_data;
 
-	ret = ccu_div_rst_register(data);
+	ret = ccu_div_of_register(data);
 	if (ret)
 		goto err_clk_unregister;
 
+	ccu_div_set_data(data);
+
 	return;
 
 err_clk_unregister:
-	ccu_div_clk_unregister(data);
+	ccu_div_clk_unregister(data, true);
 
 err_free_data:
 	ccu_div_free_data(data);
 }
+CLK_OF_DECLARE_DRIVER(ccu_axi, "baikal,bt1-ccu-axi", ccu_div_init);
+CLK_OF_DECLARE_DRIVER(ccu_sys, "baikal,bt1-ccu-sys", ccu_div_init);
 
-CLK_OF_DECLARE(ccu_axi, "baikal,bt1-ccu-axi", ccu_div_init);
-CLK_OF_DECLARE(ccu_sys, "baikal,bt1-ccu-sys", ccu_div_init);
+MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
+MODULE_DESCRIPTION("Baikal-T1 CCU Dividers clock driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/clk/baikal-t1/clk-ccu-pll.c b/drivers/clk/baikal-t1/clk-ccu-pll.c
index 2445d4b12baf..ad420c6477ee 100644
--- a/drivers/clk/baikal-t1/clk-ccu-pll.c
+++ b/drivers/clk/baikal-t1/clk-ccu-pll.c
@@ -12,6 +12,7 @@
 #define pr_fmt(fmt) "bt1-ccu-pll: " fmt
 
 #include <linux/kernel.h>
+#include <linux/platform_device.h>
 #include <linux/printk.h>
 #include <linux/slab.h>
 #include <linux/clk-provider.h>
@@ -31,13 +32,14 @@
 #define CCU_PCIE_PLL_BASE		0x018
 #define CCU_ETH_PLL_BASE		0x020
 
-#define CCU_PLL_INFO(_id, _name, _pname, _base, _flags)	\
-	{						\
-		.id = _id,				\
-		.name = _name,				\
-		.parent_name = _pname,			\
-		.base = _base,				\
-		.flags = _flags				\
+#define CCU_PLL_INFO(_id, _name, _pname, _base, _flags, _features)	\
+	{								\
+		.id = _id,						\
+		.name = _name,						\
+		.parent_name = _pname,					\
+		.base = _base,						\
+		.flags = _flags,					\
+		.features = _features,					\
 	}
 
 #define CCU_PLL_NUM			ARRAY_SIZE(pll_info)
@@ -48,6 +50,7 @@ struct ccu_pll_info {
 	const char *parent_name;
 	unsigned int base;
 	unsigned long flags;
+	unsigned long features;
 };
 
 /*
@@ -61,15 +64,15 @@ struct ccu_pll_info {
  */
 static const struct ccu_pll_info pll_info[] = {
 	CCU_PLL_INFO(CCU_CPU_PLL, "cpu_pll", "ref_clk", CCU_CPU_PLL_BASE,
-		     CLK_IS_CRITICAL),
+		     CLK_IS_CRITICAL, CCU_PLL_BASIC),
 	CCU_PLL_INFO(CCU_SATA_PLL, "sata_pll", "ref_clk", CCU_SATA_PLL_BASE,
-		     CLK_IS_CRITICAL | CLK_SET_RATE_GATE),
+		     CLK_IS_CRITICAL | CLK_SET_RATE_GATE, 0),
 	CCU_PLL_INFO(CCU_DDR_PLL, "ddr_pll", "ref_clk", CCU_DDR_PLL_BASE,
-		     CLK_IS_CRITICAL | CLK_SET_RATE_GATE),
+		     CLK_IS_CRITICAL | CLK_SET_RATE_GATE, 0),
 	CCU_PLL_INFO(CCU_PCIE_PLL, "pcie_pll", "ref_clk", CCU_PCIE_PLL_BASE,
-		     CLK_IS_CRITICAL),
+		     CLK_IS_CRITICAL, CCU_PLL_BASIC),
 	CCU_PLL_INFO(CCU_ETH_PLL, "eth_pll", "ref_clk", CCU_ETH_PLL_BASE,
-		     CLK_IS_CRITICAL | CLK_SET_RATE_GATE)
+		     CLK_IS_CRITICAL | CLK_SET_RATE_GATE, 0)
 };
 
 struct ccu_pll_data {
@@ -78,16 +81,16 @@ struct ccu_pll_data {
 	struct ccu_pll *plls[CCU_PLL_NUM];
 };
 
+static struct ccu_pll_data *pll_data;
+
 static struct ccu_pll *ccu_pll_find_desc(struct ccu_pll_data *data,
 					 unsigned int clk_id)
 {
-	struct ccu_pll *pll;
 	int idx;
 
 	for (idx = 0; idx < CCU_PLL_NUM; ++idx) {
-		pll = data->plls[idx];
-		if (pll && pll->id == clk_id)
-			return pll;
+		if (pll_info[idx].id == clk_id)
+			return data->plls[idx];
 	}
 
 	return ERR_PTR(-EINVAL);
@@ -133,14 +136,16 @@ static struct clk_hw *ccu_pll_of_clk_hw_get(struct of_phandle_args *clkspec,
 	clk_id = clkspec->args[0];
 	pll = ccu_pll_find_desc(data, clk_id);
 	if (IS_ERR(pll)) {
-		pr_info("Invalid PLL clock ID %d specified\n", clk_id);
+		if (pll != ERR_PTR(-EPROBE_DEFER))
+			pr_info("Invalid PLL clock ID %d specified\n", clk_id);
+
 		return ERR_CAST(pll);
 	}
 
 	return ccu_pll_get_clk_hw(pll);
 }
 
-static int ccu_pll_clk_register(struct ccu_pll_data *data)
+static int ccu_pll_clk_register(struct ccu_pll_data *data, bool defer)
 {
 	int idx, ret;
 
@@ -148,6 +153,14 @@ static int ccu_pll_clk_register(struct ccu_pll_data *data)
 		const struct ccu_pll_info *info = &pll_info[idx];
 		struct ccu_pll_init_data init = {0};
 
+		/* Defer non-basic PLLs allocation for the probe stage */
+		if (!!(info->features & CCU_PLL_BASIC) ^ defer) {
+			if (!data->plls[idx])
+				data->plls[idx] = ERR_PTR(-EPROBE_DEFER);
+
+			continue;
+		}
+
 		init.id = info->id;
 		init.name = info->name;
 		init.parent_name = info->parent_name;
@@ -155,6 +168,7 @@ static int ccu_pll_clk_register(struct ccu_pll_data *data)
 		init.sys_regs = data->sys_regs;
 		init.np = data->np;
 		init.flags = info->flags;
+		init.features = info->features;
 
 		data->plls[idx] = ccu_pll_hw_register(&init);
 		if (IS_ERR(data->plls[idx])) {
@@ -165,22 +179,71 @@ static int ccu_pll_clk_register(struct ccu_pll_data *data)
 		}
 	}
 
+	return 0;
+
+err_hw_unregister:
+	for (--idx; idx >= 0; --idx) {
+		if (!!(pll_info[idx].features & CCU_PLL_BASIC) ^ defer)
+			continue;
+
+		ccu_pll_hw_unregister(data->plls[idx]);
+	}
+
+	return ret;
+}
+
+static void ccu_pll_clk_unregister(struct ccu_pll_data *data, bool defer)
+{
+	int idx;
+
+	/* Uninstall only the clocks registered on the specfied stage */
+	for (idx = 0; idx < CCU_PLL_NUM; ++idx) {
+		if (!!(pll_info[idx].features & CCU_PLL_BASIC) ^ defer)
+			continue;
+
+		ccu_pll_hw_unregister(data->plls[idx]);
+	}
+}
+
+static int ccu_pll_of_register(struct ccu_pll_data *data)
+{
+	int ret;
+
 	ret = of_clk_add_hw_provider(data->np, ccu_pll_of_clk_hw_get, data);
 	if (ret) {
 		pr_err("Couldn't register PLL provider of '%s'\n",
 			of_node_full_name(data->np));
-		goto err_hw_unregister;
 	}
 
-	return 0;
+	return ret;
+}
 
-err_hw_unregister:
-	for (--idx; idx >= 0; --idx)
-		ccu_pll_hw_unregister(data->plls[idx]);
+static int ccu_pll_probe(struct platform_device *pdev)
+{
+	struct ccu_pll_data *data = pll_data;
 
-	return ret;
+	if (!data)
+		return -EINVAL;
+
+	return ccu_pll_clk_register(data, false);
 }
 
+static const struct of_device_id ccu_pll_of_match[] = {
+	{ .compatible = "baikal,bt1-ccu-pll" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ccu_pll_of_match);
+
+static struct platform_driver ccu_pll_driver = {
+	.probe  = ccu_pll_probe,
+	.driver = {
+		.name = "clk-ccu-pll",
+		.of_match_table = ccu_pll_of_match,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver(ccu_pll_driver);
+
 static __init void ccu_pll_init(struct device_node *np)
 {
 	struct ccu_pll_data *data;
@@ -194,13 +257,26 @@ static __init void ccu_pll_init(struct device_node *np)
 	if (ret)
 		goto err_free_data;
 
-	ret = ccu_pll_clk_register(data);
+	ret = ccu_pll_clk_register(data, true);
 	if (ret)
 		goto err_free_data;
 
+	ret = ccu_pll_of_register(data);
+	if (ret)
+		goto err_clk_unregister;
+
+	pll_data = data;
+
 	return;
 
+err_clk_unregister:
+	ccu_pll_clk_unregister(data, true);
+
 err_free_data:
 	ccu_pll_free_data(data);
 }
-CLK_OF_DECLARE(ccu_pll, "baikal,bt1-ccu-pll", ccu_pll_init);
+CLK_OF_DECLARE_DRIVER(ccu_pll, "baikal,bt1-ccu-pll", ccu_pll_init);
+
+MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
+MODULE_DESCRIPTION("Baikal-T1 CCU PLL clock driver");
+MODULE_LICENSE("GPL");
-- 
2.35.1

Re: [PATCH v8 0/7] clk/resets: baikal-t1: Add DDR/PCIe resets and xGMAC/SATA fixes

[Serge Semin]

Hi @Stephen.

Philipp has completed the reset-related patches review. Could you
please merge the series in so it would make it into the kernel v5.20?

-Sergey

On Tue, Jul 12, 2022 at 03:14:58PM +0300, Serge Semin wrote:
> Folks! It has been over four months since the first series submission for
> review. Please merge it in.
> 
> Short summary regarding this patchset. The series starts from fixing of
> the clocks glitching cause by the Renesas 5P49V6901 chip in some
> circumstances. Afterwards a few more modifications are introduced to
> finally finish the Baikal-T1 CCU unit support up and prepare the code
> before adding the Baikal-T1 PCIe/xGMAC support. First of all it turned out
> I specified wrong DW xGMAC PTP reference clock divider in my initial
> patches. It must be 8, not 10. Secondly I was wrong to add a joint xGMAC
> Ref and PTP clock instead of having them separately defined.  The SoC
> manual describes these clocks as separate fixed clock wrappers. Finally
> in order to close the SoC clock/reset support up we need to add the DDR
> and PCIe interfaces reset controls support. It's done in two steps. First
> I've moved the reset-controls-related code into a dedicated module. Then
> the DDR/PCIe reset-control functionality is added. As the series
> finalization we've decided to convert the Baikal-T1 clock/reset source
> drivers to mainly being the platform device driver and pre-initialize the
> basic clocks only at the early kernel boot stages.
> 
> Link: https://lore.kernel.org/linux-pci/20220324010905.15589-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v2:
> - Resubmit the series with adding @Philipp to the list of the recipients.
> 
> Link: https://lore.kernel.org/linux-pci/20220330144320.27039-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v3:
> - No comments. Just resend the series.
> - Rebased from v5.17 onto v5.18-rc3.
> 
> Link: https://lore.kernel.org/linux-clk/20220503205722.24755-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v4:
> - Completely split the CCU Dividers and Resets functionality up. (@Stephen)
> - Add a new fixes patch: "clk: baikal-t1: Actually enable SATA internal
>   ref clock".
> - Add a new fixes patch: "reset: Fix devm bulk optional exclusive control
>   getter".
> - Add a new fixes patch: "clk: vc5: Fix 5P49V6901 outputs disabling when
>   enabling FOD".
> - Add a new feagure patch: "clk: baikal-t1: Convert to platform device
>   driver".
> - Change the internal clock ID to the XGMAC-referred name.
> - Rebase onto the kernel v5.18.
> 
> Link: https://lore.kernel.org/lkml/20220610072124.8714-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v5:
> - Just resend.
> - Rebase onto the kernel v5.19-rcX.
> 
> Link: https://lore.kernel.org/linux-clk/20220624141853.7417-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v6:
> - Drop the patch
>   [PATCH RESEND v5 1/8] reset: Fix devm bulk optional exclusive control getter
>   since it has already been accepted by @Philipp.
> - Refactor the reset-control code to support the linear reset IDs only.
>   (@Philipp)
> - Combine the reset-related code into a single file. (@Philipp)
> - Drop CCU_DIV_RST_MAP() macro. It's no longer used.
> 
> Link: https://lore.kernel.org/linux-clk/20220708192725.9501-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v7:
> - Fix "Alignment should match open parenthesis" warning for the
>   pr_err() method invocations. (@Philipp)
> - Drop empty line from the sys_rst_info structure initialization block.
>   (@Philipp)
> 
> Link: https://lore.kernel.org/linux-clk/20220711154433.15415-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v8:
> - Fix "sef-deasserted" spelling in the CLK_BT1_CCU_RST config help
>   text. (@Randy)
> 
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Cc: linux-clk@vger.kernel.org
> Cc: linux-mips@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> 
> Serge Semin (7):
>   clk: vc5: Fix 5P49V6901 outputs disabling when enabling FOD
>   clk: baikal-t1: Fix invalid xGMAC PTP clock divider
>   clk: baikal-t1: Add shared xGMAC ref/ptp clocks internal parent
>   clk: baikal-t1: Add SATA internal ref clock buffer
>   clk: baikal-t1: Move reset-controls code into a dedicated module
>   clk: baikal-t1: Add DDR/PCIe directly controlled resets support
>   clk: baikal-t1: Convert to platform device driver
> 
>  drivers/clk/baikal-t1/Kconfig       |  12 +-
>  drivers/clk/baikal-t1/Makefile      |   1 +
>  drivers/clk/baikal-t1/ccu-div.c     |  84 +++++++--
>  drivers/clk/baikal-t1/ccu-div.h     |  17 +-
>  drivers/clk/baikal-t1/ccu-pll.h     |   8 +
>  drivers/clk/baikal-t1/ccu-rst.c     | 217 +++++++++++++++++++++++
>  drivers/clk/baikal-t1/ccu-rst.h     |  67 +++++++
>  drivers/clk/baikal-t1/clk-ccu-div.c | 263 ++++++++++++++++------------
>  drivers/clk/baikal-t1/clk-ccu-pll.c | 128 +++++++++++---
>  drivers/clk/clk-versaclock5.c       |   2 +-
>  include/dt-bindings/reset/bt1-ccu.h |   9 +
>  11 files changed, 647 insertions(+), 161 deletions(-)
>  create mode 100644 drivers/clk/baikal-t1/ccu-rst.c
>  create mode 100644 drivers/clk/baikal-t1/ccu-rst.h
> 
> -- 
> 2.35.1
> 

Re: [PATCH v8 0/7] clk/resets: baikal-t1: Add DDR/PCIe resets and xGMAC/SATA fixes

[Serge Semin]

Ping!

On Tue, Jul 12, 2022 at 03:16:16PM +0300, Serge Semin wrote:
> Hi @Stephen.
> 
> Philipp has completed the reset-related patches review. Could you
> please merge the series in so it would make it into the kernel v5.20?
> 
> -Sergey
> 
> On Tue, Jul 12, 2022 at 03:14:58PM +0300, Serge Semin wrote:
> > Folks! It has been over four months since the first series submission for
> > review. Please merge it in.
> > 
> > Short summary regarding this patchset. The series starts from fixing of
> > the clocks glitching cause by the Renesas 5P49V6901 chip in some
> > circumstances. Afterwards a few more modifications are introduced to
> > finally finish the Baikal-T1 CCU unit support up and prepare the code
> > before adding the Baikal-T1 PCIe/xGMAC support. First of all it turned out
> > I specified wrong DW xGMAC PTP reference clock divider in my initial
> > patches. It must be 8, not 10. Secondly I was wrong to add a joint xGMAC
> > Ref and PTP clock instead of having them separately defined.  The SoC
> > manual describes these clocks as separate fixed clock wrappers. Finally
> > in order to close the SoC clock/reset support up we need to add the DDR
> > and PCIe interfaces reset controls support. It's done in two steps. First
> > I've moved the reset-controls-related code into a dedicated module. Then
> > the DDR/PCIe reset-control functionality is added. As the series
> > finalization we've decided to convert the Baikal-T1 clock/reset source
> > drivers to mainly being the platform device driver and pre-initialize the
> > basic clocks only at the early kernel boot stages.
> > 
> > Link: https://lore.kernel.org/linux-pci/20220324010905.15589-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v2:
> > - Resubmit the series with adding @Philipp to the list of the recipients.
> > 
> > Link: https://lore.kernel.org/linux-pci/20220330144320.27039-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v3:
> > - No comments. Just resend the series.
> > - Rebased from v5.17 onto v5.18-rc3.
> > 
> > Link: https://lore.kernel.org/linux-clk/20220503205722.24755-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v4:
> > - Completely split the CCU Dividers and Resets functionality up. (@Stephen)
> > - Add a new fixes patch: "clk: baikal-t1: Actually enable SATA internal
> >   ref clock".
> > - Add a new fixes patch: "reset: Fix devm bulk optional exclusive control
> >   getter".
> > - Add a new fixes patch: "clk: vc5: Fix 5P49V6901 outputs disabling when
> >   enabling FOD".
> > - Add a new feagure patch: "clk: baikal-t1: Convert to platform device
> >   driver".
> > - Change the internal clock ID to the XGMAC-referred name.
> > - Rebase onto the kernel v5.18.
> > 
> > Link: https://lore.kernel.org/lkml/20220610072124.8714-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v5:
> > - Just resend.
> > - Rebase onto the kernel v5.19-rcX.
> > 
> > Link: https://lore.kernel.org/linux-clk/20220624141853.7417-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v6:
> > - Drop the patch
> >   [PATCH RESEND v5 1/8] reset: Fix devm bulk optional exclusive control getter
> >   since it has already been accepted by @Philipp.
> > - Refactor the reset-control code to support the linear reset IDs only.
> >   (@Philipp)
> > - Combine the reset-related code into a single file. (@Philipp)
> > - Drop CCU_DIV_RST_MAP() macro. It's no longer used.
> > 
> > Link: https://lore.kernel.org/linux-clk/20220708192725.9501-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v7:
> > - Fix "Alignment should match open parenthesis" warning for the
> >   pr_err() method invocations. (@Philipp)
> > - Drop empty line from the sys_rst_info structure initialization block.
> >   (@Philipp)
> > 
> > Link: https://lore.kernel.org/linux-clk/20220711154433.15415-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v8:
> > - Fix "sef-deasserted" spelling in the CLK_BT1_CCU_RST config help
> >   text. (@Randy)
> > 
> > Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> > Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> > Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
> > Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> > Cc: linux-clk@vger.kernel.org
> > Cc: linux-mips@vger.kernel.org
> > Cc: linux-kernel@vger.kernel.org
> > 
> > Serge Semin (7):
> >   clk: vc5: Fix 5P49V6901 outputs disabling when enabling FOD
> >   clk: baikal-t1: Fix invalid xGMAC PTP clock divider
> >   clk: baikal-t1: Add shared xGMAC ref/ptp clocks internal parent
> >   clk: baikal-t1: Add SATA internal ref clock buffer
> >   clk: baikal-t1: Move reset-controls code into a dedicated module
> >   clk: baikal-t1: Add DDR/PCIe directly controlled resets support
> >   clk: baikal-t1: Convert to platform device driver
> > 
> >  drivers/clk/baikal-t1/Kconfig       |  12 +-
> >  drivers/clk/baikal-t1/Makefile      |   1 +
> >  drivers/clk/baikal-t1/ccu-div.c     |  84 +++++++--
> >  drivers/clk/baikal-t1/ccu-div.h     |  17 +-
> >  drivers/clk/baikal-t1/ccu-pll.h     |   8 +
> >  drivers/clk/baikal-t1/ccu-rst.c     | 217 +++++++++++++++++++++++
> >  drivers/clk/baikal-t1/ccu-rst.h     |  67 +++++++
> >  drivers/clk/baikal-t1/clk-ccu-div.c | 263 ++++++++++++++++------------
> >  drivers/clk/baikal-t1/clk-ccu-pll.c | 128 +++++++++++---
> >  drivers/clk/clk-versaclock5.c       |   2 +-
> >  include/dt-bindings/reset/bt1-ccu.h |   9 +
> >  11 files changed, 647 insertions(+), 161 deletions(-)
> >  create mode 100644 drivers/clk/baikal-t1/ccu-rst.c
> >  create mode 100644 drivers/clk/baikal-t1/ccu-rst.h
> > 
> > -- 
> > 2.35.1
> >