Currently, the driver acquires and asserts/deasserts the resets
individually thereby making the driver complex to read. But this
can be simplified by using the reset_control_bulk APIs.
Use devm_reset_control_bulk_get_exclusive() API to acquire all
the resets and use reset_control_bulk_{assert/deassert}() APIs to
assert/deassert them in bulk.

Following the recommendations in 'Rockchip RK3399 TRM v1.3 Part2':

1. Split the reset controls into two groups as per section '17.5.8.1.1 PCIe
as Root Complex'.

2. Deassert the 'Pipe, MGMT Sticky, MGMT, Core' resets in groups as per
section '17.5.8.1.1 PCIe as Root Complex'. This is accomplished using the
reset_control_bulk APIs.

Signed-off-by: Anand Moon <linux.amoon@gmail.com>
---
v10: Fix some typo
v9: Improved the commit message and try to fix few review comments.
v8: I tried to address reviews and comments from Mani.
    Follow the sequence of De-assert as per the driver code.
    Drop the comment in the driver.
    Improve the commit message with the description of the TMP section.
    Improve the reason for the core functional changes in the commit
    description.
    Improve the error handling messages of the code.
v7: replace devm_reset_control_bulk_get_optional_exclusive()
        with devm_reset_control_bulk_get_exclusive()
    update the functional changes.
V6: Add reason for the split of the RESET pins.
v5: Fix the De-assert reset core as per the TRM
    De-assert the PIPE_RESET_N/MGMT_STICKY_RESET_N/MGMT_RESET_N/RESET_N
    simultaneously.
v4: use dev_err_probe in error path.
v3: Fix typo in commit message, dropped reported by.
v2: Fix compilation error reported by Intel test robot
    fixed checkpatch warning.
---
 drivers/pci/controller/pcie-rockchip.c | 154 +++++--------------------
 drivers/pci/controller/pcie-rockchip.h |  26 +++--
 2 files changed, 48 insertions(+), 132 deletions(-)

diff --git a/drivers/pci/controller/pcie-rockchip.c b/drivers/pci/controller/pcie-rockchip.c
index 2777ef0cb599..c17aa8ec80b9 100644
--- a/drivers/pci/controller/pcie-rockchip.c
+++ b/drivers/pci/controller/pcie-rockchip.c
@@ -30,7 +30,7 @@ int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *node = dev->of_node;
 	struct resource *regs;
-	int err;
+	int err, i;
 
 	if (rockchip->is_rc) {
 		regs = platform_get_resource_byname(pdev,
@@ -69,55 +69,23 @@ int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
 	if (rockchip->link_gen < 0 || rockchip->link_gen > 2)
 		rockchip->link_gen = 2;
 
-	rockchip->core_rst = devm_reset_control_get_exclusive(dev, "core");
-	if (IS_ERR(rockchip->core_rst)) {
-		if (PTR_ERR(rockchip->core_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing core reset property in node\n");
-		return PTR_ERR(rockchip->core_rst);
-	}
-
-	rockchip->mgmt_rst = devm_reset_control_get_exclusive(dev, "mgmt");
-	if (IS_ERR(rockchip->mgmt_rst)) {
-		if (PTR_ERR(rockchip->mgmt_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing mgmt reset property in node\n");
-		return PTR_ERR(rockchip->mgmt_rst);
-	}
-
-	rockchip->mgmt_sticky_rst = devm_reset_control_get_exclusive(dev,
-								"mgmt-sticky");
-	if (IS_ERR(rockchip->mgmt_sticky_rst)) {
-		if (PTR_ERR(rockchip->mgmt_sticky_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing mgmt-sticky reset property in node\n");
-		return PTR_ERR(rockchip->mgmt_sticky_rst);
-	}
-
-	rockchip->pipe_rst = devm_reset_control_get_exclusive(dev, "pipe");
-	if (IS_ERR(rockchip->pipe_rst)) {
-		if (PTR_ERR(rockchip->pipe_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing pipe reset property in node\n");
-		return PTR_ERR(rockchip->pipe_rst);
-	}
+	for (i = 0; i < ROCKCHIP_NUM_PM_RSTS; i++)
+		rockchip->pm_rsts[i].id = rockchip_pci_pm_rsts[i];
 
-	rockchip->pm_rst = devm_reset_control_get_exclusive(dev, "pm");
-	if (IS_ERR(rockchip->pm_rst)) {
-		if (PTR_ERR(rockchip->pm_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing pm reset property in node\n");
-		return PTR_ERR(rockchip->pm_rst);
-	}
+	err = devm_reset_control_bulk_get_exclusive(dev,
+						    ROCKCHIP_NUM_PM_RSTS,
+						    rockchip->pm_rsts);
+	if (err)
+		return dev_err_probe(dev, err, "Cannot get the PM reset\n");
 
-	rockchip->pclk_rst = devm_reset_control_get_exclusive(dev, "pclk");
-	if (IS_ERR(rockchip->pclk_rst)) {
-		if (PTR_ERR(rockchip->pclk_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing pclk reset property in node\n");
-		return PTR_ERR(rockchip->pclk_rst);
-	}
+	for (i = 0; i < ROCKCHIP_NUM_CORE_RSTS; i++)
+		rockchip->core_rsts[i].id = rockchip_pci_core_rsts[i];
 
-	rockchip->aclk_rst = devm_reset_control_get_exclusive(dev, "aclk");
-	if (IS_ERR(rockchip->aclk_rst)) {
-		if (PTR_ERR(rockchip->aclk_rst) != -EPROBE_DEFER)
-			dev_err(dev, "missing aclk reset property in node\n");
-		return PTR_ERR(rockchip->aclk_rst);
-	}
+	err = devm_reset_control_bulk_get_exclusive(dev,
+						    ROCKCHIP_NUM_CORE_RSTS,
+						    rockchip->core_rsts);
+	if (err)
+		return dev_err_probe(dev, err, "Cannot get the Core resets\n");
 
 	if (rockchip->is_rc) {
 		rockchip->ep_gpio = devm_gpiod_get_optional(dev, "ep",
@@ -147,23 +115,10 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
 	int err, i;
 	u32 regs;
 
-	err = reset_control_assert(rockchip->aclk_rst);
-	if (err) {
-		dev_err(dev, "assert aclk_rst err %d\n", err);
-		return err;
-	}
-
-	err = reset_control_assert(rockchip->pclk_rst);
-	if (err) {
-		dev_err(dev, "assert pclk_rst err %d\n", err);
-		return err;
-	}
-
-	err = reset_control_assert(rockchip->pm_rst);
-	if (err) {
-		dev_err(dev, "assert pm_rst err %d\n", err);
-		return err;
-	}
+	err = reset_control_bulk_assert(ROCKCHIP_NUM_PM_RSTS,
+					rockchip->pm_rsts);
+	if (err)
+		return dev_err_probe(dev, err, "Couldn't assert PM resets\n");
 
 	for (i = 0; i < MAX_LANE_NUM; i++) {
 		err = phy_init(rockchip->phys[i]);
@@ -173,47 +128,17 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
 		}
 	}
 
-	err = reset_control_assert(rockchip->core_rst);
-	if (err) {
-		dev_err(dev, "assert core_rst err %d\n", err);
-		goto err_exit_phy;
-	}
-
-	err = reset_control_assert(rockchip->mgmt_rst);
-	if (err) {
-		dev_err(dev, "assert mgmt_rst err %d\n", err);
-		goto err_exit_phy;
-	}
-
-	err = reset_control_assert(rockchip->mgmt_sticky_rst);
-	if (err) {
-		dev_err(dev, "assert mgmt_sticky_rst err %d\n", err);
-		goto err_exit_phy;
-	}
-
-	err = reset_control_assert(rockchip->pipe_rst);
-	if (err) {
-		dev_err(dev, "assert pipe_rst err %d\n", err);
-		goto err_exit_phy;
-	}
+	err = reset_control_bulk_assert(ROCKCHIP_NUM_CORE_RSTS,
+					rockchip->core_rsts);
+	if (err)
+		return dev_err_probe(dev, err, "Couldn't assert Core resets\n");
 
 	udelay(10);
 
-	err = reset_control_deassert(rockchip->pm_rst);
-	if (err) {
-		dev_err(dev, "deassert pm_rst err %d\n", err);
-		goto err_exit_phy;
-	}
-
-	err = reset_control_deassert(rockchip->aclk_rst);
+	err = reset_control_bulk_deassert(ROCKCHIP_NUM_PM_RSTS,
+					  rockchip->pm_rsts);
 	if (err) {
-		dev_err(dev, "deassert aclk_rst err %d\n", err);
-		goto err_exit_phy;
-	}
-
-	err = reset_control_deassert(rockchip->pclk_rst);
-	if (err) {
-		dev_err(dev, "deassert pclk_rst err %d\n", err);
+		dev_err(dev, "Couldn't deassert PM resets %d\n", err);
 		goto err_exit_phy;
 	}
 
@@ -252,31 +177,10 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
 		goto err_power_off_phy;
 	}
 
-	/*
-	 * Please don't reorder the deassert sequence of the following
-	 * four reset pins.
-	 */
-	err = reset_control_deassert(rockchip->mgmt_sticky_rst);
-	if (err) {
-		dev_err(dev, "deassert mgmt_sticky_rst err %d\n", err);
-		goto err_power_off_phy;
-	}
-
-	err = reset_control_deassert(rockchip->core_rst);
-	if (err) {
-		dev_err(dev, "deassert core_rst err %d\n", err);
-		goto err_power_off_phy;
-	}
-
-	err = reset_control_deassert(rockchip->mgmt_rst);
-	if (err) {
-		dev_err(dev, "deassert mgmt_rst err %d\n", err);
-		goto err_power_off_phy;
-	}
-
-	err = reset_control_deassert(rockchip->pipe_rst);
+	err = reset_control_bulk_deassert(ROCKCHIP_NUM_CORE_RSTS,
+					  rockchip->core_rsts);
 	if (err) {
-		dev_err(dev, "deassert pipe_rst err %d\n", err);
+		dev_err(dev, "Couldn't deassert Core %d\n", err);
 		goto err_power_off_phy;
 	}
 
diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index bebab80c9553..cc667c73d42f 100644
--- a/drivers/pci/controller/pcie-rockchip.h
+++ b/drivers/pci/controller/pcie-rockchip.h
@@ -15,6 +15,7 @@
 #include <linux/kernel.h>
 #include <linux/pci.h>
 #include <linux/pci-ecam.h>
+#include <linux/reset.h>
 
 /*
  * The upper 16 bits of PCIE_CLIENT_CONFIG are a write mask for the lower 16
@@ -288,18 +289,29 @@
 		(((c) << ((b) * 8 + 5)) & \
 		 ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b))
 
+#define ROCKCHIP_NUM_PM_RSTS   ARRAY_SIZE(rockchip_pci_pm_rsts)
+#define ROCKCHIP_NUM_CORE_RSTS ARRAY_SIZE(rockchip_pci_core_rsts)
+
+static const char * const rockchip_pci_pm_rsts[] = {
+	"pm",
+	"pclk",
+	"aclk",
+};
+
+static const char * const rockchip_pci_core_rsts[] = {
+	"mgmt-sticky",
+	"core",
+	"mgmt",
+	"pipe",
+};
+
 struct rockchip_pcie {
 	void	__iomem *reg_base;		/* DT axi-base */
 	void	__iomem *apb_base;		/* DT apb-base */
 	bool    legacy_phy;
 	struct  phy *phys[MAX_LANE_NUM];
-	struct	reset_control *core_rst;
-	struct	reset_control *mgmt_rst;
-	struct	reset_control *mgmt_sticky_rst;
-	struct	reset_control *pipe_rst;
-	struct	reset_control *pm_rst;
-	struct	reset_control *aclk_rst;
-	struct	reset_control *pclk_rst;
+	struct  reset_control_bulk_data pm_rsts[ROCKCHIP_NUM_PM_RSTS];
+	struct  reset_control_bulk_data core_rsts[ROCKCHIP_NUM_CORE_RSTS];
 	struct  clk_bulk_data *clks;
 	int	num_clks;
 	struct	regulator *vpcie12v; /* 12V power supply */
-- 
2.44.0

On Sat, Oct 19, 2024 at 11:31:34AM +0530, Anand Moon wrote:
> Currently, the driver acquires and asserts/deasserts the resets
> individually thereby making the driver complex to read. But this
> can be simplified by using the reset_control_bulk APIs.
> Use devm_reset_control_bulk_get_exclusive() API to acquire all
> the resets and use reset_control_bulk_{assert/deassert}() APIs to
> assert/deassert them in bulk.
> 
> Following the recommendations in 'Rockchip RK3399 TRM v1.3 Part2':
> 
> 1. Split the reset controls into two groups as per section '17.5.8.1.1 PCIe
> as Root Complex'.
> 
> 2. Deassert the 'Pipe, MGMT Sticky, MGMT, Core' resets in groups as per
> section '17.5.8.1.1 PCIe as Root Complex'. This is accomplished using the
> reset_control_bulk APIs.
> 
> Signed-off-by: Anand Moon <linux.amoon@gmail.com>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

One nitpick below. But don't need to respin as it can be fixed while applying.

> ---
> v10: Fix some typo
> v9: Improved the commit message and try to fix few review comments.
> v8: I tried to address reviews and comments from Mani.
>     Follow the sequence of De-assert as per the driver code.
>     Drop the comment in the driver.
>     Improve the commit message with the description of the TMP section.
>     Improve the reason for the core functional changes in the commit
>     description.
>     Improve the error handling messages of the code.
> v7: replace devm_reset_control_bulk_get_optional_exclusive()
>         with devm_reset_control_bulk_get_exclusive()
>     update the functional changes.
> V6: Add reason for the split of the RESET pins.
> v5: Fix the De-assert reset core as per the TRM
>     De-assert the PIPE_RESET_N/MGMT_STICKY_RESET_N/MGMT_RESET_N/RESET_N
>     simultaneously.
> v4: use dev_err_probe in error path.
> v3: Fix typo in commit message, dropped reported by.
> v2: Fix compilation error reported by Intel test robot
>     fixed checkpatch warning.
> ---
>  drivers/pci/controller/pcie-rockchip.c | 154 +++++--------------------
>  drivers/pci/controller/pcie-rockchip.h |  26 +++--
>  2 files changed, 48 insertions(+), 132 deletions(-)
> 
> diff --git a/drivers/pci/controller/pcie-rockchip.c b/drivers/pci/controller/pcie-rockchip.c
> index 2777ef0cb599..c17aa8ec80b9 100644
> --- a/drivers/pci/controller/pcie-rockchip.c
> +++ b/drivers/pci/controller/pcie-rockchip.c

[...]

> @@ -252,31 +177,10 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
>  		goto err_power_off_phy;
>  	}
>  
> -	/*
> -	 * Please don't reorder the deassert sequence of the following
> -	 * four reset pins.
> -	 */
> -	err = reset_control_deassert(rockchip->mgmt_sticky_rst);
> -	if (err) {
> -		dev_err(dev, "deassert mgmt_sticky_rst err %d\n", err);
> -		goto err_power_off_phy;
> -	}
> -
> -	err = reset_control_deassert(rockchip->core_rst);
> -	if (err) {
> -		dev_err(dev, "deassert core_rst err %d\n", err);
> -		goto err_power_off_phy;
> -	}
> -
> -	err = reset_control_deassert(rockchip->mgmt_rst);
> -	if (err) {
> -		dev_err(dev, "deassert mgmt_rst err %d\n", err);
> -		goto err_power_off_phy;
> -	}
> -
> -	err = reset_control_deassert(rockchip->pipe_rst);
> +	err = reset_control_bulk_deassert(ROCKCHIP_NUM_CORE_RSTS,
> +					  rockchip->core_rsts);
>  	if (err) {
> -		dev_err(dev, "deassert pipe_rst err %d\n", err);
> +		dev_err(dev, "Couldn't deassert Core %d\n", err);

"Couldn't deassert Core resets %d"

- Mani

-- 
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