| /* |
| * 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/spinlock.h> |
| #include <linux/irq.h> |
| #include <linux/pci.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <asm/mach-ath79/ath79.h> |
| #include <asm/mach-ath79/ar71xx_regs.h> |
| |
| #define AR724X_PCI_REG_RESET 0x18 |
| #define AR724X_PCI_REG_INT_STATUS 0x4c |
| #define AR724X_PCI_REG_INT_MASK 0x50 |
| |
| #define AR724X_PCI_RESET_LINK_UP BIT(0) |
| |
| #define AR724X_PCI_INT_DEV0 BIT(14) |
| |
| #define AR724X_PCI_IRQ_COUNT 1 |
| |
| #define AR7240_BAR0_WAR_VALUE 0xffff |
| |
| #define AR724X_PCI_CMD_INIT (PCI_COMMAND_MEMORY | \ |
| PCI_COMMAND_MASTER | \ |
| PCI_COMMAND_INVALIDATE | \ |
| PCI_COMMAND_PARITY | \ |
| PCI_COMMAND_SERR | \ |
| PCI_COMMAND_FAST_BACK) |
| |
| struct ar724x_pci_controller { |
| void __iomem *devcfg_base; |
| void __iomem *ctrl_base; |
| void __iomem *crp_base; |
| |
| int irq; |
| int irq_base; |
| |
| bool link_up; |
| bool bar0_is_cached; |
| u32 bar0_value; |
| |
| spinlock_t lock; |
| |
| struct pci_controller pci_controller; |
| struct resource io_res; |
| struct resource mem_res; |
| }; |
| |
| static inline bool ar724x_pci_check_link(struct ar724x_pci_controller *apc) |
| { |
| u32 reset; |
| |
| reset = __raw_readl(apc->ctrl_base + AR724X_PCI_REG_RESET); |
| return reset & AR724X_PCI_RESET_LINK_UP; |
| } |
| |
| static inline struct ar724x_pci_controller * |
| pci_bus_to_ar724x_controller(struct pci_bus *bus) |
| { |
| struct pci_controller *hose; |
| |
| hose = (struct pci_controller *) bus->sysdata; |
| return container_of(hose, struct ar724x_pci_controller, pci_controller); |
| } |
| |
| static int ar724x_pci_local_write(struct ar724x_pci_controller *apc, |
| int where, int size, u32 value) |
| { |
| unsigned long flags; |
| void __iomem *base; |
| u32 data; |
| int s; |
| |
| WARN_ON(where & (size - 1)); |
| |
| if (!apc->link_up) |
| return PCIBIOS_DEVICE_NOT_FOUND; |
| |
| base = apc->crp_base; |
| |
| spin_lock_irqsave(&apc->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(&apc->lock, flags); |
| return PCIBIOS_BAD_REGISTER_NUMBER; |
| } |
| |
| __raw_writel(data, base + (where & ~3)); |
| /* flush write */ |
| __raw_readl(base + (where & ~3)); |
| spin_unlock_irqrestore(&apc->lock, flags); |
| |
| return PCIBIOS_SUCCESSFUL; |
| } |
| |
| static int ar724x_pci_read(struct pci_bus *bus, unsigned int devfn, int where, |
| int size, uint32_t *value) |
| { |
| struct ar724x_pci_controller *apc; |
| unsigned long flags; |
| void __iomem *base; |
| u32 data; |
| |
| apc = pci_bus_to_ar724x_controller(bus); |
| if (!apc->link_up) |
| return PCIBIOS_DEVICE_NOT_FOUND; |
| |
| if (devfn) |
| return PCIBIOS_DEVICE_NOT_FOUND; |
| |
| base = apc->devcfg_base; |
| |
| spin_lock_irqsave(&apc->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(&apc->lock, flags); |
| |
| return PCIBIOS_BAD_REGISTER_NUMBER; |
| } |
| |
| spin_unlock_irqrestore(&apc->lock, flags); |
| |
| if (where == PCI_BASE_ADDRESS_0 && size == 4 && |
| apc->bar0_is_cached) { |
| /* use the cached value */ |
| *value = apc->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) |
| { |
| struct ar724x_pci_controller *apc; |
| unsigned long flags; |
| void __iomem *base; |
| u32 data; |
| int s; |
| |
| apc = pci_bus_to_ar724x_controller(bus); |
| if (!apc->link_up) |
| return PCIBIOS_DEVICE_NOT_FOUND; |
| |
| 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. |
| */ |
| apc->bar0_is_cached = true; |
| apc->bar0_value = value; |
| |
| value = AR7240_BAR0_WAR_VALUE; |
| } else { |
| apc->bar0_is_cached = false; |
| } |
| } |
| |
| base = apc->devcfg_base; |
| |
| spin_lock_irqsave(&apc->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(&apc->lock, flags); |
| |
| return PCIBIOS_BAD_REGISTER_NUMBER; |
| } |
| |
| __raw_writel(data, base + (where & ~3)); |
| /* flush write */ |
| __raw_readl(base + (where & ~3)); |
| spin_unlock_irqrestore(&apc->lock, flags); |
| |
| return PCIBIOS_SUCCESSFUL; |
| } |
| |
| static struct pci_ops ar724x_pci_ops = { |
| .read = ar724x_pci_read, |
| .write = ar724x_pci_write, |
| }; |
| |
| static void ar724x_pci_irq_handler(unsigned int irq, struct irq_desc *desc) |
| { |
| struct ar724x_pci_controller *apc; |
| void __iomem *base; |
| u32 pending; |
| |
| apc = irq_get_handler_data(irq); |
| base = apc->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(apc->irq_base + 0); |
| |
| else |
| spurious_interrupt(); |
| } |
| |
| static void ar724x_pci_irq_unmask(struct irq_data *d) |
| { |
| struct ar724x_pci_controller *apc; |
| void __iomem *base; |
| int offset; |
| u32 t; |
| |
| apc = irq_data_get_irq_chip_data(d); |
| base = apc->ctrl_base; |
| offset = apc->irq_base - d->irq; |
| |
| switch (offset) { |
| case 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) |
| { |
| struct ar724x_pci_controller *apc; |
| void __iomem *base; |
| int offset; |
| u32 t; |
| |
| apc = irq_data_get_irq_chip_data(d); |
| base = apc->ctrl_base; |
| offset = apc->irq_base - d->irq; |
| |
| switch (offset) { |
| case 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 ar724x_pci_irq_init(struct ar724x_pci_controller *apc, |
| int id) |
| { |
| void __iomem *base; |
| int i; |
| |
| base = apc->ctrl_base; |
| |
| __raw_writel(0, base + AR724X_PCI_REG_INT_MASK); |
| __raw_writel(0, base + AR724X_PCI_REG_INT_STATUS); |
| |
| apc->irq_base = ATH79_PCI_IRQ_BASE + (id * AR724X_PCI_IRQ_COUNT); |
| |
| for (i = apc->irq_base; |
| i < apc->irq_base + AR724X_PCI_IRQ_COUNT; i++) { |
| irq_set_chip_and_handler(i, &ar724x_pci_irq_chip, |
| handle_level_irq); |
| irq_set_chip_data(i, apc); |
| } |
| |
| irq_set_handler_data(apc->irq, apc); |
| irq_set_chained_handler(apc->irq, ar724x_pci_irq_handler); |
| } |
| |
| static int ar724x_pci_probe(struct platform_device *pdev) |
| { |
| struct ar724x_pci_controller *apc; |
| struct resource *res; |
| int id; |
| |
| id = pdev->id; |
| if (id == -1) |
| id = 0; |
| |
| apc = devm_kzalloc(&pdev->dev, sizeof(struct ar724x_pci_controller), |
| GFP_KERNEL); |
| if (!apc) |
| return -ENOMEM; |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl_base"); |
| if (!res) |
| return -EINVAL; |
| |
| apc->ctrl_base = devm_request_and_ioremap(&pdev->dev, res); |
| if (apc->ctrl_base == NULL) |
| return -EBUSY; |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg_base"); |
| if (!res) |
| return -EINVAL; |
| |
| apc->devcfg_base = devm_request_and_ioremap(&pdev->dev, res); |
| if (!apc->devcfg_base) |
| return -EBUSY; |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "crp_base"); |
| if (!res) |
| return -EINVAL; |
| |
| apc->crp_base = devm_request_and_ioremap(&pdev->dev, res); |
| if (apc->crp_base == NULL) |
| return -EBUSY; |
| |
| apc->irq = platform_get_irq(pdev, 0); |
| if (apc->irq < 0) |
| return -EINVAL; |
| |
| spin_lock_init(&apc->lock); |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_IO, "io_base"); |
| if (!res) |
| return -EINVAL; |
| |
| apc->io_res.parent = res; |
| apc->io_res.name = "PCI IO space"; |
| apc->io_res.start = res->start; |
| apc->io_res.end = res->end; |
| apc->io_res.flags = IORESOURCE_IO; |
| |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem_base"); |
| if (!res) |
| return -EINVAL; |
| |
| apc->mem_res.parent = res; |
| apc->mem_res.name = "PCI memory space"; |
| apc->mem_res.start = res->start; |
| apc->mem_res.end = res->end; |
| apc->mem_res.flags = IORESOURCE_MEM; |
| |
| apc->pci_controller.pci_ops = &ar724x_pci_ops; |
| apc->pci_controller.io_resource = &apc->io_res; |
| apc->pci_controller.mem_resource = &apc->mem_res; |
| |
| apc->link_up = ar724x_pci_check_link(apc); |
| if (!apc->link_up) |
| dev_warn(&pdev->dev, "PCIe link is down\n"); |
| |
| ar724x_pci_irq_init(apc, id); |
| |
| ar724x_pci_local_write(apc, PCI_COMMAND, 4, AR724X_PCI_CMD_INIT); |
| |
| register_pci_controller(&apc->pci_controller); |
| |
| return 0; |
| } |
| |
| static struct platform_driver ar724x_pci_driver = { |
| .probe = ar724x_pci_probe, |
| .driver = { |
| .name = "ar724x-pci", |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| static int __init ar724x_pci_init(void) |
| { |
| return platform_driver_register(&ar724x_pci_driver); |
| } |
| |
| postcore_initcall(ar724x_pci_init); |