PCI: imx: Add multi-pd support

On some chips the PCIe and PCIE_PHY blocks are in separate power domains
which can be power-gated independently. The PCI driver needs to handle
this by keeping both domain active.

This is intended for imx6sx where PCIe is in DISPLAY and PCIE_PHY in
its own domain. Defining the DISPLAY domain requires a way for PCIe to
keep it active or it will break when displays are off.

The power-domains on imx6sx are meant to look like this:
	power-domains = <&pd_disp>, <&pd_pci>;
	power-domain-names = "pcie", "pcie_phy";

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Leonard Crestez 2018-10-08 18:06:21 +00:00 committed by Lorenzo Pieralisi
parent e24b6b513e
commit 3f7cceeab8

View File

@ -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 */
@ -292,6 +299,43 @@ 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;
@ -985,6 +1029,10 @@ 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;