diff options
Diffstat (limited to 'target/linux/ar71xx/patches-3.3/140-MIPS-pci-ar724x-avoid-data-bus-error-due-to-a-missin.patch')
| -rw-r--r-- | target/linux/ar71xx/patches-3.3/140-MIPS-pci-ar724x-avoid-data-bus-error-due-to-a-missin.patch | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/target/linux/ar71xx/patches-3.3/140-MIPS-pci-ar724x-avoid-data-bus-error-due-to-a-missin.patch b/target/linux/ar71xx/patches-3.3/140-MIPS-pci-ar724x-avoid-data-bus-error-due-to-a-missin.patch new file mode 100644 index 0000000000..a05b1e7a92 --- /dev/null +++ b/target/linux/ar71xx/patches-3.3/140-MIPS-pci-ar724x-avoid-data-bus-error-due-to-a-missin.patch @@ -0,0 +1,78 @@ +From 9cfa64ddaba49975b420ce5e5020efc3301061ac Mon Sep 17 00:00:00 2001 +From: Gabor Juhos <juhosg@openwrt.org> +Date: Tue, 26 Jun 2012 10:19:46 +0200 +Subject: [PATCH 01/34] MIPS: pci-ar724x: avoid data bus error due to a missing PCIe module + +If the controller has no PCIe module attached, +accessing of the device configuration space +causes a data bus error. Avoid this by checking +the status of the PCIe link in advance, and +indicate an error if the link is down. + +Signed-off-by: Gabor Juhos <juhosg@openwrt.org> +--- + arch/mips/pci/pci-ar724x.c | 22 ++++++++++++++++++++++ + 1 files changed, 22 insertions(+), 0 deletions(-) + +--- a/arch/mips/pci/pci-ar724x.c ++++ b/arch/mips/pci/pci-ar724x.c +@@ -23,9 +23,12 @@ + #define AR724X_PCI_MEM_BASE 0x10000000 + #define AR724X_PCI_MEM_SIZE 0x08000000 + ++#define AR724X_PCI_REG_RESET 0x18 + #define AR724X_PCI_REG_INT_STATUS 0x4c + #define AR724X_PCI_REG_INT_MASK 0x50 + ++#define AR724X_PCI_RESET_LINK_UP BIT(0) ++ + #define AR724X_PCI_INT_DEV0 BIT(14) + + #define AR724X_PCI_IRQ_COUNT 1 +@@ -38,6 +41,15 @@ static void __iomem *ar724x_pci_ctrl_bas + + static u32 ar724x_pci_bar0_value; + static bool ar724x_pci_bar0_is_cached; ++static bool ar724x_pci_link_up; ++ ++static inline bool ar724x_pci_check_link(void) ++{ ++ u32 reset; ++ ++ reset = __raw_readl(ar724x_pci_ctrl_base + AR724X_PCI_REG_RESET); ++ return reset & AR724X_PCI_RESET_LINK_UP; ++} + + static int ar724x_pci_read(struct pci_bus *bus, unsigned int devfn, int where, + int size, uint32_t *value) +@@ -46,6 +58,9 @@ static int ar724x_pci_read(struct pci_bu + void __iomem *base; + u32 data; + ++ if (!ar724x_pci_link_up) ++ return PCIBIOS_DEVICE_NOT_FOUND; ++ + if (devfn) + return PCIBIOS_DEVICE_NOT_FOUND; + +@@ -96,6 +111,9 @@ static int ar724x_pci_write(struct pci_b + u32 data; + int s; + ++ if (!ar724x_pci_link_up) ++ return PCIBIOS_DEVICE_NOT_FOUND; ++ + if (devfn) + return PCIBIOS_DEVICE_NOT_FOUND; + +@@ -280,6 +298,10 @@ int __init ar724x_pcibios_init(int irq) + if (ar724x_pci_ctrl_base == NULL) + goto err_unmap_devcfg; + ++ ar724x_pci_link_up = ar724x_pci_check_link(); ++ if (!ar724x_pci_link_up) ++ pr_warn("ar724x: PCIe link is down\n"); ++ + ar724x_pci_irq_init(irq); + register_pci_controller(&ar724x_pci_controller); + |