[PATCH v10 2/4] PCI: designware: Add generic dw_pcie_wait_for_link()
From: Bjorn Helgaas
Date: Thu Feb 25 2016 - 12:37:45 EST
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;
}