On 01/28/2014 02:06 PM, Ben Dooks wrote:
Add option to enable interrupts to report any errors from
the AHB-PCI bridge to help find any issues with the bridge
when in use.
Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
---
Cc: Valentine Barshak <valentine.barshak@xxxxxxxxxxxxxxxxxx>
Cc: Simon Horman <horms@xxxxxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
Cc: linux-sh@xxxxxxxxxxxxxxx
---
drivers/pci/host/Kconfig | 9 ++++++
drivers/pci/host/pci-rcar-gen2.c | 60 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 69 insertions(+)
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 47d46c6..6d4c46e 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -33,4 +33,13 @@ config PCI_RCAR_GEN2
There are 3 internal PCI controllers available with a single
built-in EHCI/OHCI host controller present on each one.
+config PCI_RCAR_GEN2_ERRIRQ
I don't think we need to introduce another option.
Please, see my comments below.
+ bool "Enable error reporting interrupt support"
+ depends on PCI_RCAR_GEN2
+ help
+ Say Y here to enable support for the bus-error interrupts from
+ the PCI controller bridge.
+
+ This is here for aiding in debugging issues with the hardware.
+
endmenu
diff --git a/drivers/pci/host/pci-rcar-gen2.c b/drivers/pci/host/pci-rcar-gen2.c
index 674f7fe..01ba069 100644
--- a/drivers/pci/host/pci-rcar-gen2.c
+++ b/drivers/pci/host/pci-rcar-gen2.c
@@ -39,9 +39,26 @@
#define RCAR_PCI_INT_ENABLE_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x20)
#define RCAR_PCI_INT_STATUS_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x24)
+#define RCAR_PCI_INT_SIGTABORT (1 << 0)
+#define RCAR_PCI_INT_SIGRETABORT (1 << 1)
+#define RCAR_PCI_INT_REMABORT (1 << 2)
+#define RCAR_PCI_INT_PERR (1 << 3)
+#define RCAR_PCI_INT_SIGSERR (1 << 4)
+#define RCAR_PCI_INT_RESERR (1 << 5)
+#define RCAR_PCI_INT_WIN1ERR (1 << 12)
+#define RCAR_PCI_INT_WIN2ERR (1 << 13)
#define RCAR_PCI_INT_A (1 << 16)
#define RCAR_PCI_INT_B (1 << 17)
#define RCAR_PCI_INT_PME (1 << 19)
+#define RCAR_PCI_INT_ALLERRORS (RCAR_PCI_INT_SIGTABORT | \
+ RCAR_PCI_INT_SIGRETABORT | \
+ RCAR_PCI_INT_SIGRETABORT | \
+ RCAR_PCI_INT_REMABORT | \
+ RCAR_PCI_INT_PERR | \
+ RCAR_PCI_INT_SIGSERR | \
+ RCAR_PCI_INT_RESERR | \
+ RCAR_PCI_INT_WIN1ERR | \
+ RCAR_PCI_INT_WIN2ERR)
If you don't mind me nitpicking, please, follow the style of #define RCAR_AHB_BUS_MODE
#define RCAR_AHB_BUS_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x30)
#define RCAR_AHB_BUS_MMODE_HTRANS (1 << 0)
@@ -164,6 +181,47 @@ static int __init rcar_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
return priv->irq;
}
+#ifdef CONFIG_PCI_RCAR_GEN2_ERRIRQ
I think we could get away with #if IS_ENABLED(CONFIG_PCI_DEBUG) instead of
introducing another option here.
+static irqreturn_t rcar_pci_err_irq(int irq, void *pw)
+{
+ struct rcar_pci_priv *priv = pw;
+ u32 status = ioread32(priv->reg + RCAR_PCI_INT_STATUS_REG);
I'd do "& RCAR_PCI_INT_ALLERRORS" here once instead of doing
"status & RCAR_PCI_INT_ALLERRORS" twice below.
+
+ if (status & RCAR_PCI_INT_ALLERRORS) {
+ dev_err(priv->dev, "error irq: status %08x\n", status);
Some errors are not critical. For example, master abort may happen during probing.
You may want to use dev_dbg since this is all about debugging
+
+ /* clear the error(s) */
+ iowrite32(status & RCAR_PCI_INT_ALLERRORS,
+ priv->reg + RCAR_PCI_INT_STATUS_REG);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static void rcar_pci_setup_errirq(struct rcar_pci_priv *priv)
+{
+ int ret;
+ u32 val;
+
+ ret = devm_request_irq(priv->dev, priv->irq, rcar_pci_err_irq,
+ IRQF_SHARED, "error irq", priv);
+ if (ret) {
+ dev_err(priv->dev, "cannot claim IRQ for error handling\n");
+ return;
+ }
+
+ val = ioread32(priv->reg + RCAR_PCI_INT_ENABLE_REG);
+ val |= RCAR_PCI_INT_ALLERRORS;
+ iowrite32(val, priv->reg + RCAR_PCI_INT_ENABLE_REG);
+
+ dev_info(priv->dev, "irq mask now %08x\n", val);
+}
+#else
+static inline void rcar_pci_setup_errirq(struct rcar_pci_priv *priv) { }
+
+#endif
+
/* PCI host controller setup */
static int __init rcar_pci_setup(int nr, struct pci_sys_data *sys)
{
@@ -224,6 +282,8 @@ static int __init rcar_pci_setup(int nr, struct pci_sys_data *sys)
iowrite32(RCAR_PCI_INT_A | RCAR_PCI_INT_B | RCAR_PCI_INT_PME,
reg + RCAR_PCI_INT_ENABLE_REG);
+ rcar_pci_setup_errirq(priv);
+
Since priv->irq == 0 is valid and means no interrupt, you may want to
call rcar_pci_setup_errirq only if (irq > 0)
Besides, I'd probably setup the IRQ handler directly before enabling the interrupts
-- under #if IS_ENABLED(CONFIG_PCI_DEBUG) if you like -- instead of introducing
the rcar_pci_setup_errirq function and reading/modifying/writing the RCAR_PCI_INT_ENABLE_REG there.
/* Add PCI resources */
pci_add_resource(&sys->resources, &priv->io_res);
pci_add_resource(&sys->resources, &priv->mem_res);
Thanks,
Val.
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
