diff options
Diffstat (limited to 'arch/mips/pci/pci-ar724x.c')
| -rw-r--r-- | arch/mips/pci/pci-ar724x.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/arch/mips/pci/pci-ar724x.c b/arch/mips/pci/pci-ar724x.c new file mode 100644 index 00000000000..414a7459858 --- /dev/null +++ b/arch/mips/pci/pci-ar724x.c @@ -0,0 +1,292 @@ +/* + * Atheros AR724X PCI host controller driver + * + * Copyright (C) 2011 René Bolldorf <xsecute@googlemail.com> + * Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include <linux/irq.h> +#include <linux/pci.h> +#include <asm/mach-ath79/ath79.h> +#include <asm/mach-ath79/ar71xx_regs.h> +#include <asm/mach-ath79/pci.h> + +#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; + +static int ar724x_pci_read(struct pci_bus *bus, unsigned int devfn, int where, + int size, uint32_t *value) +{ + unsigned long flags; + void __iomem *base; + u32 data; + + if (devfn) + return PCIBIOS_DEVICE_NOT_FOUND; + + base = ar724x_pci_devcfg_base; + + spin_lock_irqsave(&ar724x_pci_lock, flags); + data = __raw_readl(base + (where & ~3)); + + switch (size) { + case 1: + if (where & 1) + data >>= 8; + if (where & 2) + data >>= 16; + data &= 0xff; + break; + case 2: + if (where & 2) + data >>= 16; + data &= 0xffff; + break; + case 4: + break; + default: + spin_unlock_irqrestore(&ar724x_pci_lock, flags); + + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + spin_unlock_irqrestore(&ar724x_pci_lock, flags); + + if (where == PCI_BASE_ADDRESS_0 && size == 4 && + ar724x_pci_bar0_is_cached) { + /* use the cached value */ + *value = ar724x_pci_bar0_value; + } else { + *value = data; + } + + return PCIBIOS_SUCCESSFUL; +} + +static int ar724x_pci_write(struct pci_bus *bus, unsigned int devfn, int where, + int size, uint32_t value) +{ + unsigned long flags; + void __iomem *base; + u32 data; + int s; + + if (devfn) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (soc_is_ar7240() && where == PCI_BASE_ADDRESS_0 && size == 4) { + if (value != 0xffffffff) { + /* + * WAR for a hw issue. If the BAR0 register of the + * device is set to the proper base address, the + * memory space of the device is not accessible. + * + * Cache the intended value so it can be read back, + * and write a SoC specific constant value to the + * BAR0 register in order to make the device memory + * accessible. + */ + ar724x_pci_bar0_is_cached = true; + ar724x_pci_bar0_value = value; + + value = AR7240_BAR0_WAR_VALUE; + } else { + ar724x_pci_bar0_is_cached = false; + } + } + + base = ar724x_pci_devcfg_base; + + spin_lock_irqsave(&ar724x_pci_lock, flags); + data = __raw_readl(base + (where & ~3)); + + switch (size) { + case 1: + s = ((where & 3) * 8); + data &= ~(0xff << s); + data |= ((value & 0xff) << s); + break; + case 2: + s = ((where & 2) * 8); + data &= ~(0xffff << s); + data |= ((value & 0xffff) << s); + break; + case 4: + data = value; + break; + default: + spin_unlock_irqrestore(&ar724x_pci_lock, flags); + + return PCIBIOS_BAD_REGISTER_NUMBER; + } + + __raw_writel(data, base + (where & ~3)); + /* flush write */ + __raw_readl(base + (where & ~3)); + spin_unlock_irqrestore(&ar724x_pci_lock, flags); + + return PCIBIOS_SUCCESSFUL; +} + +static struct pci_ops ar724x_pci_ops = { + .read = ar724x_pci_read, + .write = ar724x_pci_write, +}; + +static struct resource ar724x_io_resource = { + .name = "PCI IO space", + .start = 0, + .end = 0, + .flags = IORESOURCE_IO, +}; + +static struct resource ar724x_mem_resource = { + .name = "PCI memory space", + .start = AR724X_PCI_MEM_BASE, + .end = AR724X_PCI_MEM_BASE + AR724X_PCI_MEM_SIZE - 1, + .flags = IORESOURCE_MEM, +}; + +static struct pci_controller ar724x_pci_controller = { + .pci_ops = &ar724x_pci_ops, + .io_resource = &ar724x_io_resource, + .mem_resource = &ar724x_mem_resource, +}; + +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) + 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; +} |