diff options
Diffstat (limited to 'drivers/pci/controller/pci-aardvark.c')
| -rw-r--r-- | drivers/pci/controller/pci-aardvark.c | 62 |
1 files changed, 52 insertions, 10 deletions
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 051b48bd7985..c95ebe808f92 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -57,7 +57,7 @@ #define PIO_COMPLETION_STATUS_UR 1 #define PIO_COMPLETION_STATUS_CRS 2 #define PIO_COMPLETION_STATUS_CA 4 -#define PIO_NON_POSTED_REQ BIT(0) +#define PIO_NON_POSTED_REQ BIT(10) #define PIO_ADDR_LS (PIO_BASE_ADDR + 0x8) #define PIO_ADDR_MS (PIO_BASE_ADDR + 0xc) #define PIO_WR_DATA (PIO_BASE_ADDR + 0x10) @@ -125,6 +125,7 @@ #define LTSSM_MASK 0x3f #define LTSSM_L0 0x10 #define RC_BAR_CONFIG 0x300 +#define VENDOR_ID_REG (LMI_BASE_ADDR + 0x44) /* PCIe core controller registers */ #define CTRL_CORE_BASE_ADDR 0x18000 @@ -385,6 +386,16 @@ static void advk_pcie_setup_hw(struct advk_pcie *pcie) reg |= (IS_RC_MSK << IS_RC_SHIFT); advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG); + /* + * Replace incorrect PCI vendor id value 0x1b4b by correct value 0x11ab. + * VENDOR_ID_REG contains vendor id in low 16 bits and subsystem vendor + * id in high 16 bits. Updating this register changes readback value of + * read-only vendor id bits in PCIE_CORE_DEV_ID_REG register. Workaround + * for erratum 4.1: "The value of device and vendor ID is incorrect". + */ + reg = (PCI_VENDOR_ID_MARVELL << 16) | PCI_VENDOR_ID_MARVELL; + advk_writel(pcie, reg, VENDOR_ID_REG); + /* Set Advanced Error Capabilities and Control PF0 register */ reg = PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX | PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN | @@ -514,7 +525,7 @@ static int advk_pcie_wait_pio(struct advk_pcie *pcie) udelay(PIO_RETRY_DELAY); } - dev_err(dev, "config read/write timed out\n"); + dev_err(dev, "PIO read/write transfer time out\n"); return -ETIMEDOUT; } @@ -657,6 +668,35 @@ static bool advk_pcie_valid_device(struct advk_pcie *pcie, struct pci_bus *bus, return true; } +static bool advk_pcie_pio_is_running(struct advk_pcie *pcie) +{ + struct device *dev = &pcie->pdev->dev; + + /* + * Trying to start a new PIO transfer when previous has not completed + * cause External Abort on CPU which results in kernel panic: + * + * SError Interrupt on CPU0, code 0xbf000002 -- SError + * Kernel panic - not syncing: Asynchronous SError Interrupt + * + * Functions advk_pcie_rd_conf() and advk_pcie_wr_conf() are protected + * by raw_spin_lock_irqsave() at pci_lock_config() level to prevent + * concurrent calls at the same time. But because PIO transfer may take + * about 1.5s when link is down or card is disconnected, it means that + * advk_pcie_wait_pio() does not always have to wait for completion. + * + * Some versions of ARM Trusted Firmware handles this External Abort at + * EL3 level and mask it to prevent kernel panic. Relevant TF-A commit: + * https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50 + */ + if (advk_readl(pcie, PIO_START)) { + dev_err(dev, "Previous PIO read/write transfer is still running\n"); + return true; + } + + return false; +} + static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, int size, u32 *val) { @@ -673,9 +713,10 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, return pci_bridge_emul_conf_read(&pcie->bridge, where, size, val); - /* Start PIO */ - advk_writel(pcie, 0, PIO_START); - advk_writel(pcie, 1, PIO_ISR); + if (advk_pcie_pio_is_running(pcie)) { + *val = 0xffffffff; + return PCIBIOS_SET_FAILED; + } /* Program the control register */ reg = advk_readl(pcie, PIO_CTRL); @@ -694,7 +735,8 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, /* Program the data strobe */ advk_writel(pcie, 0xf, PIO_WR_DATA_STRB); - /* Start the transfer */ + /* Clear PIO DONE ISR and start the transfer */ + advk_writel(pcie, 1, PIO_ISR); advk_writel(pcie, 1, PIO_START); ret = advk_pcie_wait_pio(pcie); @@ -734,9 +776,8 @@ static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn, if (where % size) return PCIBIOS_SET_FAILED; - /* Start PIO */ - advk_writel(pcie, 0, PIO_START); - advk_writel(pcie, 1, PIO_ISR); + if (advk_pcie_pio_is_running(pcie)) + return PCIBIOS_SET_FAILED; /* Program the control register */ reg = advk_readl(pcie, PIO_CTRL); @@ -763,7 +804,8 @@ static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn, /* Program the data strobe */ advk_writel(pcie, data_strobe, PIO_WR_DATA_STRB); - /* Start the transfer */ + /* Clear PIO DONE ISR and start the transfer */ + advk_writel(pcie, 1, PIO_ISR); advk_writel(pcie, 1, PIO_START); ret = advk_pcie_wait_pio(pcie); |