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