diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0786-PCI-brcmstb-Add-DT-property-to-control-L1SS.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0786-PCI-brcmstb-Add-DT-property-to-control-L1SS.patch | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0786-PCI-brcmstb-Add-DT-property-to-control-L1SS.patch b/target/linux/bcm27xx/patches-5.4/950-0786-PCI-brcmstb-Add-DT-property-to-control-L1SS.patch new file mode 100644 index 0000000000..1d54cff647 --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0786-PCI-brcmstb-Add-DT-property-to-control-L1SS.patch @@ -0,0 +1,79 @@ +From faca7230ba711f7f966cd51bf46f83c5848a8623 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.com> +Date: Thu, 11 Jun 2020 09:57:03 +0100 +Subject: [PATCH] PCI: brcmstb: Add DT property to control L1SS + +The BRCM PCIe block has controls to enable control of the CLKREQ# +signal by the L1SS, and to gate the refclk with the CLKREQ# input. +These controls are mutually exclusive - the upstream code sets the +latter, but some use cases require the former. + +Add a Device Tree property - brcm,enable-l1ss - to switch to the +L1SS configuration. + +Signed-off-by: Phil Elwell <phil@raspberrypi.com> +--- + drivers/pci/controller/pcie-brcmstb.c | 30 ++++++++++++++++++++------- + 1 file changed, 23 insertions(+), 7 deletions(-) + +--- a/drivers/pci/controller/pcie-brcmstb.c ++++ b/drivers/pci/controller/pcie-brcmstb.c +@@ -102,8 +102,9 @@ + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI + ((win) * 8) + + #define PCIE_MISC_HARD_PCIE_HARD_DEBUG 0x4204 +-#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK 0x2 +-#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK 0x08000000 ++#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK BIT(1) ++#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_L1SS_ENABLE_MASK BIT(21) ++#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK BIT(27) + + #define PCIE_MSI_INTR2_STATUS 0x4500 + #define PCIE_MSI_INTR2_CLR 0x4508 +@@ -170,6 +171,7 @@ struct brcm_pcie { + struct pci_bus *root_bus; + struct device_node *np; + bool ssc; ++ bool l1ss; + int gen; + u64 msi_target_addr; + struct brcm_msi *msi; +@@ -834,12 +836,25 @@ static int brcm_pcie_setup(struct brcm_p + 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. +- */ + tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG); +- tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK; ++ if (pcie->l1ss) { ++ /* ++ * Enable CLKREQ# signalling include L1 Substate control of ++ * the CLKREQ# signal and the external reference clock buffer. ++ * meet requirement for Endpoints that require CLKREQ# ++ * assertion to clock active within 400ns. ++ */ ++ tmp &= ~PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK; ++ tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_L1SS_ENABLE_MASK; ++ } else { ++ /* ++ * Refclk from RC should be gated with CLKREQ# input when ++ * ASPM L0s,L1 is enabled => setting the CLKREQ_DEBUG_ENABLE ++ * field to 1. ++ */ ++ tmp &= ~PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_L1SS_ENABLE_MASK; ++ tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK; ++ } + writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG); + + return 0; +@@ -944,6 +959,7 @@ static int brcm_pcie_probe(struct platfo + pcie->gen = (ret < 0) ? 0 : ret; + + pcie->ssc = of_property_read_bool(np, "brcm,enable-ssc"); ++ pcie->l1ss = of_property_read_bool(np, "brcm,enable-l1ss"); + + ret = pci_parse_request_of_pci_ranges(pcie->dev, &bridge->windows, + &bridge->dma_ranges, NULL); |