From 1fd24b552708544ca6233ff7ba60342e9f7e5582 Mon Sep 17 00:00:00 2001 From: Gabor Juhos Date: Wed, 14 Mar 2012 10:36:07 +0100 Subject: [PATCH 16/47] MIPS: ath79: add PCI IRQ handling code for AR724X SoCs The PCI Host Controller of the AR724x SoC has a built-in IRQ controller. The current code does not supports that, so the IRQ lines wired to this controller are not usable. This leads to failed 'request_irq' calls: ath9k 0000:00:00.0: request_irq failed ath9k: probe of 0000:00:00.0 failed with error -89 This patch adds support for the IRQ controller in order to make PCI IRQs work. Signed-off-by: Gabor Juhos Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/3496/ Signed-off-by: Ralf Baechle --- arch/mips/ath79/pci.c | 3 +- arch/mips/include/asm/mach-ath79/pci.h | 4 +- arch/mips/pci/pci-ar724x.c | 118 +++++++++++++++++++++++++++++++- 3 files changed, 120 insertions(+), 5 deletions(-) --- a/arch/mips/ath79/pci.c +++ b/arch/mips/ath79/pci.c @@ -10,6 +10,7 @@ #include #include +#include #include #include "pci.h" @@ -50,7 +51,7 @@ int pcibios_plat_dev_init(struct pci_dev int __init ath79_register_pci(void) { if (soc_is_ar724x()) - return ar724x_pcibios_init(); + return ar724x_pcibios_init(ATH79_CPU_IRQ_IP2); return -ENODEV; } --- a/arch/mips/include/asm/mach-ath79/pci.h +++ b/arch/mips/include/asm/mach-ath79/pci.h @@ -12,9 +12,9 @@ #define __ASM_MACH_ATH79_PCI_H #if defined(CONFIG_PCI) && defined(CONFIG_SOC_AR724X) -int ar724x_pcibios_init(void); +int ar724x_pcibios_init(int irq); #else -static inline int ar724x_pcibios_init(void) { return 0; } +static inline int ar724x_pcibios_init(int irq) { return 0; } #endif #endif /* __ASM_MACH_ATH79_PCI_H */ --- a/arch/mips/pci/pci-ar724x.c +++ b/arch/mips/pci/pci-ar724x.c @@ -8,19 +8,32 @@ * by the Free Software Foundation. */ +#include #include #include +#include #include #define AR724X_PCI_CFG_BASE 0x14000000 #define AR724X_PCI_CFG_SIZE 0x1000 +#define AR724X_PCI_CTRL_BASE (AR71XX_APB_BASE + 0x000f0000) +#define AR724X_PCI_CTRL_SIZE 0x100 + #define AR724X_PCI_MEM_BASE 0x10000000 #define AR724X_PCI_MEM_SIZE 0x08000000 +#define AR724X_PCI_REG_INT_STATUS 0x4c +#define AR724X_PCI_REG_INT_MASK 0x50 + +#define AR724X_PCI_INT_DEV0 BIT(14) + +#define AR724X_PCI_IRQ_COUNT 1 + #define AR7240_BAR0_WAR_VALUE 0xffff static DEFINE_SPINLOCK(ar724x_pci_lock); static void __iomem *ar724x_pci_devcfg_base; +static void __iomem *ar724x_pci_ctrl_base; static u32 ar724x_pci_bar0_value; static bool ar724x_pci_bar0_is_cached; @@ -164,14 +177,115 @@ static struct pci_controller ar724x_pci_ .mem_resource = &ar724x_mem_resource, }; -int __init ar724x_pcibios_init(void) +static void ar724x_pci_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + void __iomem *base; + u32 pending; + + base = ar724x_pci_ctrl_base; + + pending = __raw_readl(base + AR724X_PCI_REG_INT_STATUS) & + __raw_readl(base + AR724X_PCI_REG_INT_MASK); + + if (pending & AR724X_PCI_INT_DEV0) + generic_handle_irq(ATH79_PCI_IRQ(0)); + + else + spurious_interrupt(); +} + +static void ar724x_pci_irq_unmask(struct irq_data *d) +{ + void __iomem *base; + u32 t; + + base = ar724x_pci_ctrl_base; + + switch (d->irq) { + case ATH79_PCI_IRQ(0): + t = __raw_readl(base + AR724X_PCI_REG_INT_MASK); + __raw_writel(t | AR724X_PCI_INT_DEV0, + base + AR724X_PCI_REG_INT_MASK); + /* flush write */ + __raw_readl(base + AR724X_PCI_REG_INT_MASK); + } +} + +static void ar724x_pci_irq_mask(struct irq_data *d) +{ + void __iomem *base; + u32 t; + + base = ar724x_pci_ctrl_base; + + switch (d->irq) { + case ATH79_PCI_IRQ(0): + t = __raw_readl(base + AR724X_PCI_REG_INT_MASK); + __raw_writel(t & ~AR724X_PCI_INT_DEV0, + base + AR724X_PCI_REG_INT_MASK); + + /* flush write */ + __raw_readl(base + AR724X_PCI_REG_INT_MASK); + + t = __raw_readl(base + AR724X_PCI_REG_INT_STATUS); + __raw_writel(t | AR724X_PCI_INT_DEV0, + base + AR724X_PCI_REG_INT_STATUS); + + /* flush write */ + __raw_readl(base + AR724X_PCI_REG_INT_STATUS); + } +} + +static struct irq_chip ar724x_pci_irq_chip = { + .name = "AR724X PCI ", + .irq_mask = ar724x_pci_irq_mask, + .irq_unmask = ar724x_pci_irq_unmask, + .irq_mask_ack = ar724x_pci_irq_mask, +}; + +static void __init ar724x_pci_irq_init(int irq) +{ + void __iomem *base; + int i; + + base = ar724x_pci_ctrl_base; + + __raw_writel(0, base + AR724X_PCI_REG_INT_MASK); + __raw_writel(0, base + AR724X_PCI_REG_INT_STATUS); + + BUILD_BUG_ON(ATH79_PCI_IRQ_COUNT < AR724X_PCI_IRQ_COUNT); + + for (i = ATH79_PCI_IRQ_BASE; + i < ATH79_PCI_IRQ_BASE + AR724X_PCI_IRQ_COUNT; i++) + irq_set_chip_and_handler(i, &ar724x_pci_irq_chip, + handle_level_irq); + + irq_set_chained_handler(irq, ar724x_pci_irq_handler); +} + +int __init ar724x_pcibios_init(int irq) { + int ret; + + ret = -ENOMEM; + ar724x_pci_devcfg_base = ioremap(AR724X_PCI_CFG_BASE, AR724X_PCI_CFG_SIZE); if (ar724x_pci_devcfg_base == NULL) - return -ENOMEM; + goto err; + ar724x_pci_ctrl_base = ioremap(AR724X_PCI_CTRL_BASE, + AR724X_PCI_CTRL_SIZE); + if (ar724x_pci_ctrl_base == NULL) + goto err_unmap_devcfg; + + ar724x_pci_irq_init(irq); register_pci_controller(&ar724x_pci_controller); return PCIBIOS_SUCCESSFUL; + +err_unmap_devcfg: + iounmap(ar724x_pci_devcfg_base); +err: + return ret; }