diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index cd5be284789e..efe8b5f7bf8c 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c @@ -603,6 +603,7 @@ static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u3 u32 reg; unsigned int status; char *strcomp_status, *str_posted; + int ret; reg = advk_readl(pcie, PIO_STAT); status = (reg & PIO_COMPLETION_STATUS_MASK) >> @@ -627,6 +628,7 @@ static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u3 case PIO_COMPLETION_STATUS_OK: if (reg & PIO_ERR_STATUS) { strcomp_status = "COMP_ERR"; + ret = -EFAULT; break; } /* Get the read result */ @@ -634,9 +636,11 @@ static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u3 *val = advk_readl(pcie, PIO_RD_DATA); /* No error */ strcomp_status = NULL; + ret = 0; break; case PIO_COMPLETION_STATUS_UR: strcomp_status = "UR"; + ret = -EOPNOTSUPP; break; case PIO_COMPLETION_STATUS_CRS: if (allow_crs && val) { @@ -654,6 +658,7 @@ static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u3 */ *val = CFG_RD_CRS_VAL; strcomp_status = NULL; + ret = 0; break; } /* PCIe r4.0, sec 2.3.2, says: @@ -669,21 +674,24 @@ static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u3 * Request and taking appropriate action, e.g., complete the * Request to the host as a failed transaction. * - * To simplify implementation do not re-issue the Configuration - * Request and complete the Request as a failed transaction. + * So return -EAGAIN and caller (pci-aardvark.c driver) will + * re-issue request again up to the PIO_RETRY_CNT retries. */ strcomp_status = "CRS"; + ret = -EAGAIN; break; case PIO_COMPLETION_STATUS_CA: strcomp_status = "CA"; + ret = -ECANCELED; break; default: strcomp_status = "Unknown"; + ret = -EINVAL; break; } if (!strcomp_status) - return 0; + return ret; if (reg & PIO_NON_POSTED_REQ) str_posted = "Non-posted"; @@ -693,7 +701,7 @@ static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u3 dev_dbg(dev, "%s PIO Response Status: %s, %#x @ %#x\n", str_posted, strcomp_status, reg, advk_readl(pcie, PIO_ADDR_LS)); - return -EFAULT; + return ret; } static int advk_pcie_wait_pio(struct advk_pcie *pcie) @@ -701,13 +709,13 @@ static int advk_pcie_wait_pio(struct advk_pcie *pcie) struct device *dev = &pcie->pdev->dev; int i; - for (i = 0; i < PIO_RETRY_CNT; i++) { + for (i = 1; i <= PIO_RETRY_CNT; i++) { u32 start, isr; start = advk_readl(pcie, PIO_START); isr = advk_readl(pcie, PIO_ISR); if (!start && isr) - return 0; + return i; udelay(PIO_RETRY_DELAY); } @@ -898,6 +906,7 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, int size, u32 *val) { struct advk_pcie *pcie = bus->sysdata; + int retry_count; bool allow_crs; u32 reg; int ret; @@ -940,16 +949,22 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn, /* Program the data strobe */ advk_writel(pcie, 0xf, PIO_WR_DATA_STRB); - /* Clear PIO DONE ISR and start the transfer */ - advk_writel(pcie, 1, PIO_ISR); - advk_writel(pcie, 1, PIO_START); + retry_count = 0; + do { + /* 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); - if (ret < 0) - goto try_crs; + ret = advk_pcie_wait_pio(pcie); + if (ret < 0) + goto try_crs; + + retry_count += ret; + + /* Check PIO status and get the read result */ + ret = advk_pcie_check_pio_status(pcie, allow_crs, val); + } while (ret == -EAGAIN && retry_count < PIO_RETRY_CNT); - /* Check PIO status and get the read result */ - ret = advk_pcie_check_pio_status(pcie, allow_crs, val); if (ret < 0) goto fail; @@ -981,6 +996,7 @@ static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn, struct advk_pcie *pcie = bus->sysdata; u32 reg; u32 data_strobe = 0x0; + int retry_count; int offset; int ret; @@ -1022,19 +1038,22 @@ 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); - /* Clear PIO DONE ISR and start the transfer */ - advk_writel(pcie, 1, PIO_ISR); - advk_writel(pcie, 1, PIO_START); + retry_count = 0; + do { + /* 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); - if (ret < 0) - return PCIBIOS_SET_FAILED; + ret = advk_pcie_wait_pio(pcie); + if (ret < 0) + return PCIBIOS_SET_FAILED; - ret = advk_pcie_check_pio_status(pcie, false, NULL); - if (ret < 0) - return PCIBIOS_SET_FAILED; + retry_count += ret; - return PCIBIOS_SUCCESSFUL; + ret = advk_pcie_check_pio_status(pcie, false, NULL); + } while (ret == -EAGAIN && retry_count < PIO_RETRY_CNT); + + return ret < 0 ? PCIBIOS_SET_FAILED : PCIBIOS_SUCCESSFUL; } static struct pci_ops advk_pcie_ops = {