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path: root/drivers/pci/controller/dwc/pci-imx6.c
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Diffstat (limited to 'drivers/pci/controller/dwc/pci-imx6.c')
-rw-r--r--drivers/pci/controller/dwc/pci-imx6.c102
1 files changed, 97 insertions, 5 deletions
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 88af6bff945f..52e47dac028f 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -27,6 +27,8 @@
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/reset.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
#include "pcie-designware.h"
@@ -59,6 +61,11 @@ struct imx6_pcie {
u32 tx_swing_low;
int link_gen;
struct regulator *vpcie;
+
+ /* power domain for pcie */
+ struct device *pd_pcie;
+ /* power domain for pcie phy */
+ struct device *pd_pcie_phy;
};
/* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
@@ -67,6 +74,7 @@ struct imx6_pcie {
#define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200
/* PCIe Root Complex registers (memory-mapped) */
+#define PCIE_RC_IMX6_MSI_CAP 0x50
#define PCIE_RC_LCR 0x7c
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1
#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2
@@ -290,6 +298,43 @@ static int imx6q_pcie_abort_handler(unsigned long addr,
return 1;
}
+static int imx6_pcie_attach_pd(struct device *dev)
+{
+ struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
+ struct device_link *link;
+
+ /* Do nothing when in a single power domain */
+ if (dev->pm_domain)
+ return 0;
+
+ imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie");
+ if (IS_ERR(imx6_pcie->pd_pcie))
+ return PTR_ERR(imx6_pcie->pd_pcie);
+ link = device_link_add(dev, imx6_pcie->pd_pcie,
+ DL_FLAG_STATELESS |
+ DL_FLAG_PM_RUNTIME |
+ DL_FLAG_RPM_ACTIVE);
+ if (!link) {
+ dev_err(dev, "Failed to add device_link to pcie pd.\n");
+ return -EINVAL;
+ }
+
+ imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
+ if (IS_ERR(imx6_pcie->pd_pcie_phy))
+ return PTR_ERR(imx6_pcie->pd_pcie_phy);
+
+ device_link_add(dev, imx6_pcie->pd_pcie_phy,
+ DL_FLAG_STATELESS |
+ DL_FLAG_PM_RUNTIME |
+ DL_FLAG_RPM_ACTIVE);
+ if (IS_ERR(link)) {
+ dev_err(dev, "Failed to add device_link to pcie_phy pd: %ld\n", PTR_ERR(link));
+ return PTR_ERR(link);
+ }
+
+ return 0;
+}
+
static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
{
struct device *dev = imx6_pcie->pci->dev;
@@ -765,8 +810,28 @@ static void imx6_pcie_ltssm_disable(struct device *dev)
static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
{
- reset_control_assert(imx6_pcie->turnoff_reset);
- reset_control_deassert(imx6_pcie->turnoff_reset);
+ struct device *dev = imx6_pcie->pci->dev;
+
+ /* Some variants have a turnoff reset in DT */
+ if (imx6_pcie->turnoff_reset) {
+ reset_control_assert(imx6_pcie->turnoff_reset);
+ reset_control_deassert(imx6_pcie->turnoff_reset);
+ goto pm_turnoff_sleep;
+ }
+
+ /* Others poke directly at IOMUXC registers */
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_PM_TURN_OFF,
+ IMX6SX_GPR12_PCIE_PM_TURN_OFF);
+ regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
+ break;
+ default:
+ dev_err(dev, "PME_Turn_Off not implemented\n");
+ return;
+ }
/*
* Components with an upstream port must respond to
@@ -775,6 +840,7 @@ static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
* The standard recommends a 1-10ms timeout after which to
* proceed anyway as if acks were received.
*/
+pm_turnoff_sleep:
usleep_range(1000, 10000);
}
@@ -784,18 +850,31 @@ static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
clk_disable_unprepare(imx6_pcie->pcie_phy);
clk_disable_unprepare(imx6_pcie->pcie_bus);
- if (imx6_pcie->variant == IMX7D) {
+ switch (imx6_pcie->variant) {
+ case IMX6SX:
+ clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
+ break;
+ case IMX7D:
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
+ break;
+ default:
+ break;
}
}
+static inline bool imx6_pcie_supports_suspend(struct imx6_pcie *imx6_pcie)
+{
+ return (imx6_pcie->variant == IMX7D ||
+ imx6_pcie->variant == IMX6SX);
+}
+
static int imx6_pcie_suspend_noirq(struct device *dev)
{
struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
- if (imx6_pcie->variant != IMX7D)
+ if (!imx6_pcie_supports_suspend(imx6_pcie))
return 0;
imx6_pcie_pm_turnoff(imx6_pcie);
@@ -811,7 +890,7 @@ static int imx6_pcie_resume_noirq(struct device *dev)
struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
struct pcie_port *pp = &imx6_pcie->pci->pp;
- if (imx6_pcie->variant != IMX7D)
+ if (!imx6_pcie_supports_suspend(imx6_pcie))
return 0;
imx6_pcie_assert_core_reset(imx6_pcie);
@@ -840,6 +919,7 @@ static int imx6_pcie_probe(struct platform_device *pdev)
struct resource *dbi_base;
struct device_node *node = dev->of_node;
int ret;
+ u16 val;
imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
if (!imx6_pcie)
@@ -977,10 +1057,22 @@ static int imx6_pcie_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, imx6_pcie);
+ ret = imx6_pcie_attach_pd(dev);
+ if (ret)
+ return ret;
+
ret = imx6_add_pcie_port(imx6_pcie, pdev);
if (ret < 0)
return ret;
+ if (pci_msi_enabled()) {
+ val = dw_pcie_readw_dbi(pci, PCIE_RC_IMX6_MSI_CAP +
+ PCI_MSI_FLAGS);
+ val |= PCI_MSI_FLAGS_ENABLE;
+ dw_pcie_writew_dbi(pci, PCIE_RC_IMX6_MSI_CAP + PCI_MSI_FLAGS,
+ val);
+ }
+
return 0;
}