Re: [PATCH v10 2/4] PCI: designware: Add generic dw_pcie_wait_for_link()

From: Joao Pinto
Date: Thu Feb 25 2016 - 21:43:11 EST


Hi! This patch seems OK also.
I did not received the 3/4 and 4/4 patches.

Thanks.

On 2/26/2016 1:37 AM, Bjorn Helgaas wrote:
> From: Joao Pinto <Joao.Pinto@xxxxxxxxxxxx>
>
> Several DesignWare-based drivers (dra7xx, exynos, imx6 and spear13xx) had
> similar loops waiting for the link to come up.
>
> FIXME Doesn't update keystone
> FIXME Doesn't update qcom
>
> 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.
>
> [bhelgaas: changelog, split into its own patch]
> Signed-off-by: Joao Pinto <jpinto@xxxxxxxxxxxx>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> ---
> drivers/pci/host/pci-dra7xx.c | 11 +++--------
> drivers/pci/host/pci-exynos.c | 11 ++---------
> drivers/pci/host/pci-imx6.c | 11 +++--------
> drivers/pci/host/pcie-designware.c | 19 +++++++++++++++++++
> drivers/pci/host/pcie-designware.h | 6 ++++++
> drivers/pci/host/pcie-spear13xx.c | 12 ++----------
> 6 files changed, 35 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c
> index 923607b..8d3d350 100644
> --- a/drivers/pci/host/pci-dra7xx.c
> +++ b/drivers/pci/host/pci-dra7xx.c
> @@ -10,7 +10,6 @@
> * published by the Free Software Foundation.
> */
>
> -#include <linux/delay.h>
> #include <linux/err.h>
> #include <linux/interrupt.h>
> #include <linux/irq.h>
> @@ -108,7 +107,6 @@ static int dra7xx_pcie_establish_link(struct pcie_port *pp)
> {
> struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
> u32 reg;
> - unsigned int retries;
>
> if (dw_pcie_link_up(pp)) {
> dev_err(pp->dev, "link is already up\n");
> @@ -119,13 +117,10 @@ static int dra7xx_pcie_establish_link(struct pcie_port *pp)
> reg |= LTSSM_EN;
> dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);
>
> - for (retries = 0; retries < 1000; retries++) {
> - if (dw_pcie_link_up(pp))
> - return 0;
> - usleep_range(10, 20);
> - }
> + /* check if the link is up or not */
> + if (!dw_pcie_wait_for_link(pp))
> + return 0;
>
> - dev_err(pp->dev, "link is not up\n");
> return -EINVAL;
> }
>
> diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c
> index d997d22..41f3248 100644
> --- a/drivers/pci/host/pci-exynos.c
> +++ b/drivers/pci/host/pci-exynos.c
> @@ -318,7 +318,6 @@ static int exynos_pcie_establish_link(struct pcie_port *pp)
> {
> struct exynos_pcie *exynos_pcie = to_exynos_pcie(pp);
> u32 val;
> - unsigned int retries;
>
> if (dw_pcie_link_up(pp)) {
> dev_err(pp->dev, "Link already up\n");
> @@ -357,13 +356,8 @@ static int exynos_pcie_establish_link(struct pcie_port *pp)
> PCIE_APP_LTSSM_ENABLE);
>
> /* check if the link is up or not */
> - for (retries = 0; retries < 10; retries++) {
> - if (dw_pcie_link_up(pp)) {
> - dev_info(pp->dev, "Link up\n");
> - return 0;
> - }
> - mdelay(100);
> - }
> + if (!dw_pcie_wait_for_link(pp))
> + return 0;
>
> while (exynos_phy_readl(exynos_pcie, PCIE_PHY_PLL_LOCKED) == 0) {
> val = exynos_blk_readl(exynos_pcie, PCIE_PHY_PLL_LOCKED);
> @@ -372,7 +366,6 @@ static int exynos_pcie_establish_link(struct pcie_port *pp)
> /* power off phy */
> exynos_pcie_power_off_phy(pp);
>
> - dev_err(pp->dev, "PCIe Link Fail\n");
> return -EINVAL;
> }
>
> diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
> index fe60096..c53da17 100644
> --- a/drivers/pci/host/pci-imx6.c
> +++ b/drivers/pci/host/pci-imx6.c
> @@ -330,15 +330,10 @@ static void imx6_pcie_init_phy(struct pcie_port *pp)
>
> static int imx6_pcie_wait_for_link(struct pcie_port *pp)
> {
> - unsigned int retries;
> -
> - for (retries = 0; retries < 200; retries++) {
> - if (dw_pcie_link_up(pp))
> - return 0;
> - usleep_range(100, 1000);
> - }
> + /* check if the link is up or not */
> + if (!dw_pcie_wait_for_link(pp))
> + return 0;
>
> - 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));
> diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
> index 2171682..4fff2d2 100644
> --- a/drivers/pci/host/pcie-designware.c
> +++ b/drivers/pci/host/pcie-designware.c
> @@ -22,6 +22,7 @@
> #include <linux/pci_regs.h>
> #include <linux/platform_device.h>
> #include <linux/types.h>
> +#include <linux/delay.h>
>
> #include "pcie-designware.h"
>
> @@ -380,6 +381,24 @@ static struct msi_controller dw_pcie_msi_chip = {
> .teardown_irq = dw_msi_teardown_irq,
> };
>
> +int dw_pcie_wait_for_link(struct pcie_port *pp)
> +{
> + int retries;
> +
> + /* check if the link is up or not */
> + for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
> + if (dw_pcie_link_up(pp)) {
> + dev_info(pp->dev, "link up\n");
> + return 0;
> + }
> + usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
> + }
> +
> + dev_err(pp->dev, "phy link never came up\n");
> +
> + return -EINVAL;
> +}
> +
> int dw_pcie_link_up(struct pcie_port *pp)
> {
> if (pp->ops->link_up)
> diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
> index 2356d29..f437f9b 100644
> --- a/drivers/pci/host/pcie-designware.h
> +++ b/drivers/pci/host/pcie-designware.h
> @@ -22,6 +22,11 @@
> #define MAX_MSI_IRQS 32
> #define MAX_MSI_CTRLS (MAX_MSI_IRQS / 32)
>
> +/* Parameters for the waiting for link up routine */
> +#define LINK_WAIT_MAX_RETRIES 10
> +#define LINK_WAIT_USLEEP_MIN 90000
> +#define LINK_WAIT_USLEEP_MAX 100000
> +
> struct pcie_port {
> struct device *dev;
> u8 root_bus_nr;
> @@ -76,6 +81,7 @@ int dw_pcie_cfg_read(void __iomem *addr, int size, u32 *val);
> int dw_pcie_cfg_write(void __iomem *addr, int size, u32 val);
> irqreturn_t dw_handle_msi_irq(struct pcie_port *pp);
> void dw_pcie_msi_init(struct pcie_port *pp);
> +int dw_pcie_wait_for_link(struct pcie_port *pp);
> int dw_pcie_link_up(struct pcie_port *pp);
> void dw_pcie_setup_rc(struct pcie_port *pp);
> int dw_pcie_host_init(struct pcie_port *pp);
> diff --git a/drivers/pci/host/pcie-spear13xx.c b/drivers/pci/host/pcie-spear13xx.c
> index a6cd823..0e5a2f1 100644
> --- a/drivers/pci/host/pcie-spear13xx.c
> +++ b/drivers/pci/host/pcie-spear13xx.c
> @@ -13,7 +13,6 @@
> */
>
> #include <linux/clk.h>
> -#include <linux/delay.h>
> #include <linux/interrupt.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> @@ -149,7 +148,6 @@ static int spear13xx_pcie_establish_link(struct pcie_port *pp)
> struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
> struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
> u32 exp_cap_off = EXP_CAP_ID_OFFSET;
> - unsigned int retries;
>
> if (dw_pcie_link_up(pp)) {
> dev_err(pp->dev, "link already up\n");
> @@ -201,15 +199,9 @@ static int spear13xx_pcie_establish_link(struct pcie_port *pp)
> &app_reg->app_ctrl_0);
>
> /* check if the link is up or not */
> - for (retries = 0; retries < 10; retries++) {
> - if (dw_pcie_link_up(pp)) {
> - dev_info(pp->dev, "link up\n");
> - return 0;
> - }
> - mdelay(100);
> - }
> + if (!dw_pcie_wait_for_link(pp))
> + return 0;
>
> - dev_err(pp->dev, "link Fail\n");
> return -EINVAL;
> }
>
>
> --
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