PCI: designware: Add generic dw_pcie_wait_for_link()

Several DesignWare-based drivers (dra7xx, exynos, imx6, keystone, qcom, and
spear13xx) had similar loops waiting for the link to come up.

Add a generic dw_pcie_wait_for_link() for use by all these drivers so the
waiting is done consistently, e.g., always using usleep_range() rather than
mdelay() and using similar timeouts and retry counts.

Note that this changes the Keystone link training/wait for link strategy,
so we initiate link training, then wait longer for the link to come up
before re-initiating link training.

[bhelgaas: changelog, split into its own patch, update pci-keystone.c, pcie-qcom.c]
Signed-off-by: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Pratyush Anand <pratyush.anand@gmail.com>
This commit is contained in:
Joao Pinto
2016-03-10 14:44:35 -06:00
committed by Bjorn Helgaas
parent c1678ffcde
commit 886bc5ceb5
8 changed files with 39 additions and 59 deletions

View File

@@ -116,8 +116,6 @@ static irqreturn_t qcom_pcie_msi_irq_handler(int irq, void *arg)
static int qcom_pcie_establish_link(struct qcom_pcie *pcie)
{
struct device *dev = pcie->dev;
unsigned int retries = 0;
u32 val;
if (dw_pcie_link_up(&pcie->pp))
@@ -128,15 +126,7 @@ static int qcom_pcie_establish_link(struct qcom_pcie *pcie)
val |= PCIE20_ELBI_SYS_CTRL_LT_ENABLE;
writel(val, pcie->elbi + PCIE20_ELBI_SYS_CTRL);
do {
if (dw_pcie_link_up(&pcie->pp))
return 0;
usleep_range(250, 1000);
} while (retries < 200);
dev_warn(dev, "phy link never came up\n");
return -ETIMEDOUT;
return dw_pcie_wait_for_link(&pcie->pp);
}
static int qcom_pcie_get_resources_v0(struct qcom_pcie *pcie)