From cfa41c94f0cbb3eeb11540b9b85efe9090a06f39 Mon Sep 17 00:00:00 2001 From: Jim Quinlan Date: Mon, 25 Jul 2022 11:12:51 -0400 Subject: [PATCH] PCI: brcmstb: Split post-link up initialization to brcm_pcie_start_link() Previously brcm_pcie_setup() initialized the Root Port itself as well as doing the actual link-up. Split brcm_pcie_setup() into two functions: - brcm_pcie_setup(), which initializes everything that does not require the link itself to be up, and - brcm_pcie_start_link(), which brings up the link and initializes things that depend on the link being up. [bhelgaas: condense commit log, deferring details for future changes] Link: https://lore.kernel.org/r/20220725151258.42574-3-jim2101024@gmail.com Signed-off-by: Jim Quinlan Signed-off-by: Bjorn Helgaas Tested-by: Florian Fainelli --- drivers/pci/controller/pcie-brcmstb.c | 111 +++++++++++++++----------- 1 file changed, 64 insertions(+), 47 deletions(-) diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 52a53c49c965f..56631d4b42e93 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -857,17 +857,13 @@ static inline int brcm_pcie_get_rc_bar2_size_and_offset(struct brcm_pcie *pcie, static int brcm_pcie_setup(struct brcm_pcie *pcie) { - struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie); u64 rc_bar2_offset, rc_bar2_size; void __iomem *base = pcie->base; - struct device *dev = pcie->dev; + struct pci_host_bridge *bridge; struct resource_entry *entry; - bool ssc_good = false; - struct resource *res; - int num_out_wins = 0; - u16 nlw, cls, lnksta; - int i, ret, memc; u32 tmp, burst, aspm_support; + int num_out_wins = 0; + int ret, memc; /* Reset the bridge */ pcie->bridge_sw_init_set(pcie, 1); @@ -943,6 +939,11 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie) else pcie->msi_target_addr = BRCM_MSI_TARGET_ADDR_GT_4GB; + if (!brcm_pcie_rc_mode(pcie)) { + dev_err(pcie->dev, "PCIe RC controller misconfigured as Endpoint\n"); + return -EINVAL; + } + /* disable the PCIe->GISB memory window (RC_BAR1) */ tmp = readl(base + PCIE_MISC_RC_BAR1_CONFIG_LO); tmp &= ~PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK; @@ -953,31 +954,27 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie) tmp &= ~PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK; writel(tmp, base + PCIE_MISC_RC_BAR3_CONFIG_LO); - if (pcie->gen) - brcm_pcie_set_gen(pcie, pcie->gen); - - /* Unassert the fundamental reset */ - pcie->perst_set(pcie, 0); + /* Don't advertise L0s capability if 'aspm-no-l0s' */ + aspm_support = PCIE_LINK_STATE_L1; + if (!of_property_read_bool(pcie->np, "aspm-no-l0s")) + aspm_support |= PCIE_LINK_STATE_L0S; + tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY); + u32p_replace_bits(&tmp, aspm_support, + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK); + writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY); /* - * Give the RC/EP time to wake up, before trying to configure RC. - * Intermittently check status for link-up, up to a total of 100ms. + * For config space accesses on the RC, show the right class for + * a PCIe-PCIe bridge (the default setting is to be EP mode). */ - for (i = 0; i < 100 && !brcm_pcie_link_up(pcie); i += 5) - msleep(5); - - if (!brcm_pcie_link_up(pcie)) { - dev_err(dev, "link down\n"); - return -ENODEV; - } - - if (!brcm_pcie_rc_mode(pcie)) { - dev_err(dev, "PCIe misconfigured; is in EP mode\n"); - return -EINVAL; - } + tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3); + u32p_replace_bits(&tmp, 0x060400, + PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK); + writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3); + bridge = pci_host_bridge_from_priv(pcie); resource_list_for_each_entry(entry, &bridge->windows) { - res = entry->res; + struct resource *res = entry->res; if (resource_type(res) != IORESOURCE_MEM) continue; @@ -1006,23 +1003,41 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie) num_out_wins++; } - /* Don't advertise L0s capability if 'aspm-no-l0s' */ - aspm_support = PCIE_LINK_STATE_L1; - if (!of_property_read_bool(pcie->np, "aspm-no-l0s")) - aspm_support |= PCIE_LINK_STATE_L0S; - tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY); - u32p_replace_bits(&tmp, aspm_support, - PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK); - writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY); + /* PCIe->SCB endian mode for BAR */ + tmp = readl(base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1); + u32p_replace_bits(&tmp, PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN, + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK); + writel(tmp, base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1); + + return 0; +} + +static int brcm_pcie_start_link(struct brcm_pcie *pcie) +{ + struct device *dev = pcie->dev; + void __iomem *base = pcie->base; + u16 nlw, cls, lnksta; + bool ssc_good = false; + u32 tmp; + int ret, i; + + /* Unassert the fundamental reset */ + pcie->perst_set(pcie, 0); /* - * For config space accesses on the RC, show the right class for - * a PCIe-PCIe bridge (the default setting is to be EP mode). + * Give the RC/EP time to wake up, before trying to configure RC. + * Intermittently check status for link-up, up to a total of 100ms. */ - tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3); - u32p_replace_bits(&tmp, 0x060400, - PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK); - writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3); + for (i = 0; i < 100 && !brcm_pcie_link_up(pcie); i += 5) + msleep(5); + + if (!brcm_pcie_link_up(pcie)) { + dev_err(dev, "link down\n"); + return -ENODEV; + } + + if (pcie->gen) + brcm_pcie_set_gen(pcie, pcie->gen); if (pcie->ssc) { ret = brcm_pcie_set_ssc(pcie); @@ -1039,12 +1054,6 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie) pci_speed_string(pcie_link_speed[cls]), nlw, ssc_good ? "(SSC)" : "(!SSC)"); - /* PCIe->SCB endian mode for BAR */ - tmp = readl(base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1); - u32p_replace_bits(&tmp, PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN, - PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK); - writel(tmp, base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1); - /* * Refclk from RC should be gated with CLKREQ# input when ASPM L0s,L1 * is enabled => setting the CLKREQ_DEBUG_ENABLE field to 1. @@ -1212,6 +1221,10 @@ static int brcm_pcie_resume(struct device *dev) if (ret) goto err_reset; + ret = brcm_pcie_start_link(pcie); + if (ret) + goto err_reset; + if (pcie->msi) brcm_msi_set_regs(pcie->msi); @@ -1401,6 +1414,10 @@ static int brcm_pcie_probe(struct platform_device *pdev) if (ret) goto fail; + ret = brcm_pcie_start_link(pcie); + if (ret) + goto fail; + pcie->hw_rev = readl(pcie->base + PCIE_MISC_REVISION); if (pcie->type == BCM4908 && pcie->hw_rev >= BRCM_PCIE_HW_REV_3_20) { dev_err(pcie->dev, "hardware revision with unsupported PERST# setup\n"); -- 2.39.5