[PATCH v2] PCI: dw-rockchip: Add system PM support
Niklas Cassel
cassel at kernel.org
Tue Apr 15 06:09:29 PDT 2025
On Fri, Apr 11, 2025 at 02:14:08PM +0800, Shawn Lin wrote:
> This patch adds system PM support for Rockchip platforms by adding .pme_turn_off
> and .get_ltssm hook and tries to reuse possible exist code.
>
> It's tested on RK3576 EVB1 board with Some NVMes and PCIe-2-SATA/XHCI devices.
> And check the PCIe protocol analyzer to make sure the L2 process fits the spec.
>
> [ 1.541394] nvme nvme0: missing or invalid SUBNQN field.
> [ 1.548755] nvme nvme0: allocated 64 MiB host memory buffer (16 segments).
> [ 1.562235] nvme nvme0: 8/0/0 default/read/poll queues
> [ 1.563930] nvme nvme0: Ignoring bogus Namespace Identifiers
>
> echo N > /sys/module/printk/parameters/console_suspend
> echo core > /sys/power/pm_test
> echo mem > /sys/power/state
>
> [ 58.443602] PM: suspend entry (deep)
> [ 58.444005] Filesystems sync: 0.000 seconds
> [ 58.445542] Freezing user space processes
> [ 58.447096] Freezing user space processes completed (elapsed 0.001 seconds)
> [ 58.447718] OOM killer disabled.
> [ 58.448008] Freezing remaining freezable tasks
> [ 58.449080] Freezing remaining freezable tasks completed (elapsed 0.000 seconds)
>
> ...
>
> [ 58.797070] rockchip-dw-pcie 22400000.pcie: PCIe Gen.2 x1 link up
> [ 58.835953] OOM killer enabled.
> [ 58.836262] Restarting tasks ... done.
> [ 58.839241] random: crng reseeded on system resumption
> [ 58.840679] PM: suspend exit
> [ 59.500036] nvme nvme0: 8/0/0 default/read/poll queues
> [ 59.500909] nvme nvme0: Ignoring bogus Namespace Identifiers
>
> time dd if=/dev/nvme0n1 of=/dev/null bs=1M count=1000
> 1000+0 records in
> 1000+0 records out
> real 0m 5.51s
> user 0m 0.00s
> sys 0m 0.71s
>
> Signed-off-by: Shawn Lin <shawn.lin at rock-chips.com>
> ---
>
> Changes in v2:
> - Use NOIRQ_SYSTEM_SLEEP_PM_OPS
>
> drivers/pci/controller/dwc/pcie-dw-rockchip.c | 185 +++++++++++++++++++++++---
> 1 file changed, 169 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> index 56acfea..7246a49 100644
> --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> @@ -21,6 +21,7 @@
> #include <linux/regmap.h>
> #include <linux/reset.h>
>
> +#include "../../pci.h"
> #include "pcie-designware.h"
>
> /*
> @@ -37,8 +38,14 @@
> #define PCIE_CLIENT_EP_MODE HIWORD_UPDATE(0xf0, 0x0)
> #define PCIE_CLIENT_ENABLE_LTSSM HIWORD_UPDATE_BIT(0xc)
> #define PCIE_CLIENT_DISABLE_LTSSM HIWORD_UPDATE(0x0c, 0x8)
> +#define PCIE_CLIENT_INTR_STATUS_MSG_RX 0x04
> #define PCIE_CLIENT_INTR_STATUS_MISC 0x10
> #define PCIE_CLIENT_INTR_MASK_MISC 0x24
> +#define PCIE_CLIENT_POWER 0x2c
> +#define PCIE_CLIENT_MSG_GEN 0x34
> +#define PME_READY_ENTER_L23 BIT(3)
> +#define PME_TURN_OFF (BIT(4) | BIT(20))
> +#define PME_TO_ACK (BIT(9) | BIT(25))
> #define PCIE_SMLH_LINKUP BIT(16)
> #define PCIE_RDLH_LINKUP BIT(17)
> #define PCIE_LINKUP (PCIE_SMLH_LINKUP | PCIE_RDLH_LINKUP)
> @@ -63,6 +70,7 @@ struct rockchip_pcie {
> struct gpio_desc *rst_gpio;
> struct regulator *vpcie3v3;
> struct irq_domain *irq_domain;
> + u32 intx;
> const struct rockchip_pcie_of_data *data;
> };
>
> @@ -159,6 +167,13 @@ static u32 rockchip_pcie_get_ltssm(struct rockchip_pcie *rockchip)
> return rockchip_pcie_readl_apb(rockchip, PCIE_CLIENT_LTSSM_STATUS);
> }
>
> +static u32 rockchip_pcie_get_pure_ltssm(struct dw_pcie *pci)
> +{
> + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci);
> +
> + return rockchip_pcie_get_ltssm(rockchip) & PCIE_LTSSM_STATUS_MASK;
> +}
> +
> static void rockchip_pcie_enable_ltssm(struct rockchip_pcie *rockchip)
> {
> rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_ENABLE_LTSSM,
> @@ -248,8 +263,46 @@ static int rockchip_pcie_host_init(struct dw_pcie_rp *pp)
> return 0;
> }
>
> +static void rockchip_pcie_pme_turn_off(struct dw_pcie_rp *pp)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> + struct rockchip_pcie *rockchip = to_rockchip_pcie(pci);
> + struct device *dev = rockchip->pci.dev;
> + int ret;
> + u32 status;
> +
> + /* 1. Broadcast PME_Turn_Off Message, bit 4 self-clear once done */
> + rockchip_pcie_writel_apb(rockchip, PME_TURN_OFF, PCIE_CLIENT_MSG_GEN);
> + ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_MSG_GEN,
> + status, !(status & BIT(4)), PCIE_PME_TO_L2_TIMEOUT_US / 10,
> + PCIE_PME_TO_L2_TIMEOUT_US);
> + if (ret) {
> + dev_warn(dev, "Failed to send PME_Turn_Off\n");
> + return;
> + }
> +
> + /* 2. Wait for PME_TO_Ack, bit 9 will be set once received */
> + ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_INTR_STATUS_MSG_RX,
> + status, status & BIT(9), PCIE_PME_TO_L2_TIMEOUT_US / 10,
> + PCIE_PME_TO_L2_TIMEOUT_US);
> + if (ret) {
> + dev_warn(dev, "Failed to receive PME_TO_Ack\n");
> + return;
> + }
> +
> + /* 3. Clear PME_TO_Ack and Wait for ready to enter L23 message */
> + rockchip_pcie_writel_apb(rockchip, PME_TO_ACK, PCIE_CLIENT_INTR_STATUS_MSG_RX);
> + ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_POWER,
> + status, status & PME_READY_ENTER_L23,
> + PCIE_PME_TO_L2_TIMEOUT_US / 10,
> + PCIE_PME_TO_L2_TIMEOUT_US);
> + if (ret)
> + dev_err(dev, "Failed to get ready to enter L23 message\n");
> +}
> +
> static const struct dw_pcie_host_ops rockchip_pcie_host_ops = {
> .init = rockchip_pcie_host_init,
> + .pme_turn_off = rockchip_pcie_pme_turn_off,
> };
>
> /*
> @@ -430,6 +483,7 @@ static const struct dw_pcie_ops dw_pcie_ops = {
> .link_up = rockchip_pcie_link_up,
> .start_link = rockchip_pcie_start_link,
> .stop_link = rockchip_pcie_stop_link,
> + .get_ltssm = rockchip_pcie_get_pure_ltssm,
> };
>
> static irqreturn_t rockchip_pcie_rc_sys_irq_thread(int irq, void *arg)
> @@ -489,13 +543,32 @@ static irqreturn_t rockchip_pcie_ep_sys_irq_thread(int irq, void *arg)
> return IRQ_HANDLED;
> }
>
> +static void rockchip_pcie_ltssm_enable_control_mode(struct rockchip_pcie *rockchip, u32 mode)
> +{
> + u32 val;
> +
> + /* LTSSM enable control mode */
> + val = HIWORD_UPDATE_BIT(PCIE_LTSSM_ENABLE_ENHANCE);
> + rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL);
> +
> + rockchip_pcie_writel_apb(rockchip, mode, PCIE_CLIENT_GENERAL_CONTROL);
> +}
> +
> +static void rockchip_pcie_unmask_dll_indicator(struct rockchip_pcie *rockchip)
> +{
> + u32 val;
> +
> + /* unmask DLL up/down indicator */
> + val = HIWORD_UPDATE(PCIE_RDLH_LINK_UP_CHGED, 0);
> + rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_INTR_MASK_MISC);
> +}
> +
> static int rockchip_pcie_configure_rc(struct platform_device *pdev,
> struct rockchip_pcie *rockchip)
> {
> struct device *dev = &pdev->dev;
> struct dw_pcie_rp *pp;
> int irq, ret;
> - u32 val;
>
> if (!IS_ENABLED(CONFIG_PCIE_ROCKCHIP_DW_HOST))
> return -ENODEV;
> @@ -512,12 +585,7 @@ static int rockchip_pcie_configure_rc(struct platform_device *pdev,
> return ret;
> }
>
> - /* LTSSM enable control mode */
> - val = HIWORD_UPDATE_BIT(PCIE_LTSSM_ENABLE_ENHANCE);
> - rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL);
> -
> - rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_RC_MODE,
> - PCIE_CLIENT_GENERAL_CONTROL);
> + rockchip_pcie_ltssm_enable_control_mode(rockchip, PCIE_CLIENT_RC_MODE);
>
> pp = &rockchip->pci.pp;
> pp->ops = &rockchip_pcie_host_ops;
> @@ -529,9 +597,7 @@ static int rockchip_pcie_configure_rc(struct platform_device *pdev,
> return ret;
> }
>
> - /* unmask DLL up/down indicator */
> - val = HIWORD_UPDATE(PCIE_RDLH_LINK_UP_CHGED, 0);
> - rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_INTR_MASK_MISC);
> + rockchip_pcie_unmask_dll_indicator(rockchip);
>
> return ret;
> }
> @@ -558,12 +624,7 @@ static int rockchip_pcie_configure_ep(struct platform_device *pdev,
> return ret;
> }
>
> - /* LTSSM enable control mode */
> - val = HIWORD_UPDATE_BIT(PCIE_LTSSM_ENABLE_ENHANCE);
> - rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL);
> -
> - rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_EP_MODE,
> - PCIE_CLIENT_GENERAL_CONTROL);
> + rockchip_pcie_ltssm_enable_control_mode(rockchip, PCIE_CLIENT_EP_MODE);
>
> rockchip->pci.ep.ops = &rockchip_pcie_ep_ops;
> rockchip->pci.ep.page_size = SZ_64K;
> @@ -677,6 +738,92 @@ static int rockchip_pcie_probe(struct platform_device *pdev)
> return ret;
> }
>
> +static int rockchip_pcie_suspend(struct device *dev)
> +{
> + struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> + struct dw_pcie *pci = &rockchip->pci;
> + int ret;
> +
> + rockchip->intx = rockchip_pcie_readl_apb(rockchip, PCIE_CLIENT_INTR_MASK_LEGACY);
> +
> + ret = dw_pcie_suspend_noirq(pci);
> + if (ret) {
> + dev_err(dev, "failed to suspend\n");
> + return ret;
> + }
> +
> + rockchip_pcie_phy_deinit(rockchip);
> + clk_bulk_disable_unprepare(rockchip->clk_cnt, rockchip->clks);
> + reset_control_assert(rockchip->rst);
> + if (rockchip->vpcie3v3)
> + regulator_disable(rockchip->vpcie3v3);
> + gpiod_set_value_cansleep(rockchip->rst_gpio, 0);
> +
> + return 0;
> +}
> +
> +static int rockchip_pcie_resume(struct device *dev)
> +{
> + struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> + struct dw_pcie *pci = &rockchip->pci;
> + int ret;
> +
> + reset_control_assert(rockchip->rst);
> +
> + ret = clk_bulk_prepare_enable(rockchip->clk_cnt, rockchip->clks);
> + if (ret) {
> + dev_err(dev, "clock init failed\n");
> + goto err_clk;
> + }
> +
> + if (rockchip->vpcie3v3) {
> + ret = regulator_enable(rockchip->vpcie3v3);
> + if (ret)
> + goto err_power;
> + }
> +
> + ret = phy_init(rockchip->phy);
> + if (ret) {
> + dev_err(dev, "fail to init phy\n");
> + goto err_phy_init;
> + }
> +
> + ret = phy_power_on(rockchip->phy);
> + if (ret) {
> + dev_err(dev, "fail to power on phy\n");
> + goto err_phy_on;
> + }
> +
> + reset_control_deassert(rockchip->rst);
> +
> + rockchip_pcie_writel_apb(rockchip, HIWORD_UPDATE(0xffff, rockchip->intx),
> + PCIE_CLIENT_INTR_MASK_LEGACY);
> +
> + rockchip_pcie_ltssm_enable_control_mode(rockchip, PCIE_CLIENT_RC_MODE);
Here you are setting PCIE_CLIENT_RC_MODE unconditionally.
I really don't think that you have tested these callbacks with EP mode.
If we look at pcie-qcom.c and pcie-qcom-ep.c, dev_pm_ops is defined in
pcie-qcom.c, but not in pcie-qcom-ep.c.
Perhaps it is starting to be time to have two separate drivers also for
rockchip?
> + rockchip_pcie_unmask_dll_indicator(rockchip);
> +
> + ret = dw_pcie_resume_noirq(pci);
> + if (ret) {
> + dev_err(dev, "fail to resume\n");
> + goto err_resume;
> + }
> +
> + return 0;
> +
> +err_resume:
> + phy_power_off(rockchip->phy);
> +err_phy_on:
> + phy_exit(rockchip->phy);
> +err_phy_init:
> + if (rockchip->vpcie3v3)
> + regulator_disable(rockchip->vpcie3v3);
> +err_power:
> + clk_bulk_disable_unprepare(rockchip->clk_cnt, rockchip->clks);
> +err_clk:
> + reset_control_deassert(rockchip->rst);
> + return ret;
> +}
> +
> static const struct rockchip_pcie_of_data rockchip_pcie_rc_of_data_rk3568 = {
> .mode = DW_PCIE_RC_TYPE,
> };
> @@ -707,11 +854,17 @@ static const struct of_device_id rockchip_pcie_of_match[] = {
> {},
> };
>
> +static const struct dev_pm_ops rockchip_pcie_pm_ops = {
> + NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend,
> + rockchip_pcie_resume)
> +};
> +
> static struct platform_driver rockchip_pcie_driver = {
> .driver = {
> .name = "rockchip-dw-pcie",
> .of_match_table = rockchip_pcie_of_match,
> .suppress_bind_attrs = true,
> + .pm = &rockchip_pcie_pm_ops,
> },
> .probe = rockchip_pcie_probe,
> };
> --
> 2.7.4
>
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