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-rw-r--r--arch/mips/pci/pci-ar724x.c292
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 0000000..414a745
--- /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;
+}