Hi Gab, This patch is part of the on going work of integrating a designware platform driver that is SoC agnostic. This code replication issue was raised during discussions. Thanks Joao On 2/8/2016 1:03 PM, Gabriele Paoloni wrote: > Hi Joao > >> -----Original Message----- >> From: linux-pci-owner@xxxxxxxxxxxxxxx [mailto:linux-pci- >> owner@xxxxxxxxxxxxxxx] On Behalf Of Joao Pinto >> Sent: 08 February 2016 12:44 >> To: helgaas@xxxxxxxxxx >> Cc: arnd@xxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linux- >> kernel@xxxxxxxxxxxxxxx; CARLOS.PALMINHA@xxxxxxxxxxxx; Joao Pinto >> Subject: [PATCH] link up validation moved to pcie-designware >> >> This patch goal is to centralize in pcie-designware the link up >> validation. A new function was added to pci-designware that is >> responsible for doing such a task. This was implemented in a form that >> permits flexibility for all SoCs. > > Looking at the patch I don't think this is really needed, > it seems to me like it makes more confusion in reading the > drivers code. > > It is clear that each HW IP has got his own transient time > in setting the link up, this is clear looking at the code > of the single drivers now. > > With the modification you are proposing we are seeing > drivers calls with magic numbers and the need for the > reader to go and look into the designware framework to > understand a function that is not even designware > specific (in fact all these drivers need to wait different > times according to their HW IP and some other drivers do > not need to wait at all...) > > BTW I am quite new to PCIe so let's see what the other guys > think... > > Cheers > > Gab > >> >> Signed-off-by: Joao Pinto <jpinto@xxxxxxxxxxxx> >> --- >> 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 | 20 ++++++++++++++++++++ >> drivers/pci/host/pcie-designware.h | 2 ++ >> drivers/pci/host/pcie-spear13xx.c | 12 ++---------- >> 6 files changed, 32 insertions(+), 35 deletions(-) >> >> diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci- >> dra7xx.c >> index 8c36880..e425944 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_check_link_is_up(pp, 1000, 10, 20)) >> + 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 01095e1..770c45a 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_check_link_is_up(pp, 10, 100000, 110000)) >> + 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 22e8224..9e323be 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_check_link_is_up(pp, 200, 100, 1000)) >> + 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 540f077..6725231 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 +381,25 @@ static struct msi_controller dw_pcie_msi_chip = { >> .teardown_irq = dw_msi_teardown_irq, >> }; >> >> +int dw_pcie_check_link_is_up(struct pcie_port *pp, int max_ret, int >> sleep_min, >> + int sleep_max) >> +{ >> + int retries; >> + >> + /* check if the link is up or not */ >> + for (retries = 0; retries < max_ret; retries++) { >> + if (dw_pcie_link_up(pp)) { >> + dev_info(pp->dev, "link up\n"); >> + return 0; >> + } >> + usleep_range(sleep_min, sleep_max); >> + } >> + >> + dev_err(pp->dev, "phy link never came up\n"); >> + >> + return 1; >> +} >> + >> 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..b077fe0 100644 >> --- a/drivers/pci/host/pcie-designware.h >> +++ b/drivers/pci/host/pcie-designware.h >> @@ -76,6 +76,8 @@ 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_check_link_is_up(struct pcie_port *pp, int max_ret, int >> sleep_min, >> + int sleep_max); >> 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 b95b756..5c24595 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_check_link_is_up(pp, 10, 100000, 110000)) >> + return 0; >> >> - dev_err(pp->dev, "link Fail\n"); >> return -EINVAL; >> } >> >> -- >> 1.8.1.5 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
