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

@@ -330,19 +330,14 @@ static void imx6_pcie_init_phy(struct pcie_port *pp)
static int imx6_pcie_wait_for_link(struct pcie_port *pp)
{
unsigned int retries;
/* check if the link is up or not */
if (!dw_pcie_wait_for_link(pp))
return 0;
for (retries = 0; retries < 200; retries++) {
if (dw_pcie_link_up(pp))
return 0;
usleep_range(100, 1000);
}
dev_err(pp->dev, "phy link never came up\n");
dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
return -EINVAL;
return -ETIMEDOUT;
}
static int imx6_pcie_wait_for_speed_change(struct pcie_port *pp)