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-rw-r--r--drivers/pci/controller/pci-aardvark.c67
1 files changed, 43 insertions, 24 deletions
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index 6eea7d5aac26..ff243be8410c 100644
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -692,6 +692,7 @@ 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) >>
@@ -716,6 +717,7 @@ 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 */
@@ -723,9 +725,11 @@ 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) {
@@ -743,6 +747,7 @@ 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:
@@ -758,21 +763,24 @@ 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";
@@ -782,7 +790,7 @@ 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)
@@ -790,13 +798,13 @@ 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);
}
@@ -1068,6 +1076,7 @@ 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;
@@ -1110,16 +1119,22 @@ 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;
@@ -1151,6 +1166,7 @@ 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;
@@ -1192,19 +1208,22 @@ 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 = {