Add PCI host controller driver and DMA address calculation hook.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@xxxxxxxxx>
---
arch/mips/ar231x/Kconfig | 7 +
arch/mips/ar231x/ar2315.c | 19 ++
arch/mips/include/asm/mach-ar231x/ar2315_regs.h | 24 ++
arch/mips/include/asm/mach-ar231x/dma-coherence.h | 18 +-
arch/mips/pci/Makefile | 1 +
arch/mips/pci/pci-ar2315.c | 345 ++++++++++++++++++++++
6 files changed, 411 insertions(+), 3 deletions(-)
create mode 100644 arch/mips/pci/pci-ar2315.c
diff --git a/arch/mips/ar231x/Kconfig b/arch/mips/ar231x/Kconfig
index 88ca061..f4bf354 100644
--- a/arch/mips/ar231x/Kconfig
+++ b/arch/mips/ar231x/Kconfig
@@ -9,3 +9,10 @@ config SOC_AR2315
depends on AR231X
select GPIO_AR2315
default y
+
+config PCI_AR2315
+ bool "Atheros AR2315 PCI controller support"
+ depends on SOC_AR2315
+ select HW_HAS_PCI
+ select PCI
+ default y
diff --git a/arch/mips/ar231x/ar2315.c b/arch/mips/ar231x/ar2315.c
index 62cf548..a9fbe4b 100644
--- a/arch/mips/ar231x/ar2315.c
+++ b/arch/mips/ar231x/ar2315.c
@@ -103,6 +103,11 @@ static void ar2315_irq_dispatch(void)
{
u32 pending = read_c0_status() & read_c0_cause();
+#ifdef CONFIG_PCI_AR2315
+ if (pending & CAUSEF_IP5)
+ do_IRQ(AR2315_IRQ_LCBUS_PCI);
+ else
+#endif
if (pending & CAUSEF_IP2)
do_IRQ(AR2315_IRQ_MISC);
else if (pending & CAUSEF_IP7)
@@ -355,3 +360,17 @@ void __init ar2315_prom_init(void)
ar231x_board.devid = devid;
}
+#ifdef CONFIG_PCI_AR2315
+static int __init ar2315_pci_init(void)
+{
+ struct platform_device *pdev;
+
+ if (!is_2315() || ar231x_devtype != DEV_TYPE_AR2315)
+ return -ENODEV;
+
+ pdev = platform_device_register_simple("ar2315-pci", -1, NULL, 0);
+
+ return pdev ? 0 : -ENODEV;
+}
+arch_initcall(ar2315_pci_init);
+#endif
diff --git a/arch/mips/include/asm/mach-ar231x/ar2315_regs.h b/arch/mips/include/asm/mach-ar231x/ar2315_regs.h
index dd7df42..5dcc1dc 100644
--- a/arch/mips/include/asm/mach-ar231x/ar2315_regs.h
+++ b/arch/mips/include/asm/mach-ar231x/ar2315_regs.h
@@ -38,6 +38,16 @@
#define AR2315_MISC_IRQ_COUNT 9
/*
+ * PCI interrupts, which share IP5
+ * Keep ordered according to AR2315_PCI_INT_XXX bits
+ */
+#define AR2315_PCI_IRQ_BASE 0x50
+#define AR2315_PCI_IRQ_EXT (AR2315_PCI_IRQ_BASE+0)
+#define AR2315_PCI_IRQ_ABORT (AR2315_PCI_IRQ_BASE+1)
+#define AR2315_PCI_IRQ_COUNT 2
+#define AR2315_PCI_IRQ_SHIFT 25 /* in AR2315_PCI_INT_STATUS */
+
+/*
* Address map
*/
#define AR2315_SPI_READ 0x08000000 /* SPI flash */
@@ -554,4 +564,18 @@
#define AR2315_IRCFG_SEQ_END_WIN_THRESH 0x001f0000
#define AR2315_IRCFG_NUM_BACKOFF_WORDS 0x01e00000
+/*
+ * We need some arbitrary non-zero value to be programmed to the BAR1 register
+ * of PCI host controller to enable DMA. The same value should be used as the
+ * offset to calculate the physical address of DMA buffer for PCI devices.
+ */
+#define AR2315_PCI_HOST_SDRAM_BASEADDR 0x20000000
+
+/* ??? access BAR */
+#define AR2315_PCI_HOST_MBAR0 0x10000000
+/* RAM access BAR */
+#define AR2315_PCI_HOST_MBAR1 AR2315_PCI_HOST_SDRAM_BASEADDR
+/* ??? access BAR */
+#define AR2315_PCI_HOST_MBAR2 0x30000000
+
#endif /* __ASM_MACH_AR231X_AR2315_REGS_H */
diff --git a/arch/mips/include/asm/mach-ar231x/dma-coherence.h b/arch/mips/include/asm/mach-ar231x/dma-coherence.h
index ed32240..90065c1 100644
--- a/arch/mips/include/asm/mach-ar231x/dma-coherence.h
+++ b/arch/mips/include/asm/mach-ar231x/dma-coherence.h
@@ -11,23 +11,35 @@
#define __ASM_MACH_AR231X_DMA_COHERENCE_H
#include <linux/device.h>
+#include <ar2315_regs.h>
+
+static inline dma_addr_t ar231x_dev_offset(struct device *dev)
+{
+#ifdef CONFIG_PCI
+ extern struct bus_type pci_bus_type;
+
+ if (dev && dev->bus == &pci_bus_type)
+ return AR2315_PCI_HOST_SDRAM_BASEADDR;
+#endif
+ return 0;
+}
static inline dma_addr_t
plat_map_dma_mem(struct device *dev, void *addr, size_t size)
{
- return virt_to_phys(addr);
+ return virt_to_phys(addr) + ar231x_dev_offset(dev);
}
static inline dma_addr_t
plat_map_dma_mem_page(struct device *dev, struct page *page)
{
- return page_to_phys(page);
+ return page_to_phys(page) + ar231x_dev_offset(dev);
}
static inline unsigned long
plat_dma_addr_to_phys(struct device *dev, dma_addr_t dma_addr)
{
- return dma_addr;
+ return dma_addr - ar231x_dev_offset(dev);
}
static inline void
diff --git a/arch/mips/pci/Makefile b/arch/mips/pci/Makefile
index 6523d55..ab6c857 100644
--- a/arch/mips/pci/Makefile
+++ b/arch/mips/pci/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_BCM47XX) += pci-bcm47xx.o
obj-$(CONFIG_BCM63XX) += pci-bcm63xx.o fixup-bcm63xx.o \
ops-bcm63xx.o
obj-$(CONFIG_MIPS_ALCHEMY) += pci-alchemy.o
+obj-$(CONFIG_PCI_AR2315) += pci-ar2315.o
obj-$(CONFIG_SOC_AR71XX) += pci-ar71xx.o
obj-$(CONFIG_PCI_AR724X) += pci-ar724x.o
obj-$(CONFIG_MIPS_PCI_VIRTIO) += pci-virtio-guest.o
diff --git a/arch/mips/pci/pci-ar2315.c b/arch/mips/pci/pci-ar2315.c
new file mode 100644
index 0000000..f53d2e8
--- /dev/null
+++ b/arch/mips/pci/pci-ar2315.c
@@ -0,0 +1,345 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * Both AR2315 and AR2316 chips have PCI interface unit, which supports DMA
+ * and interrupt. PCI interface supports MMIO access method, but does not
+ * seem to support I/O ports.
+ *
+ * Read/write operation in the region 0x80000000-0xBFFFFFFF causes
+ * a memory read/write command on the PCI bus. 30 LSBs of address on
+ * the bus are taken from memory read/write request and 2 MSBs are
+ * determined by PCI unit configuration.
+ *
+ * To work with the configuration space instead of memory is necessary set
+ * the CFG_SEL bit in the PCI_MISC_CONFIG register.
+ *
+ * Devices on the bus can perform DMA requests via chip BAR1. PCI host
+ * controller BARs are programmend as if an external device is programmed.
+ * Which means that during configuration, IDSEL pin of the chip should be
+ * asserted.
+ *
+ * We know (and support) only one board that uses the PCI interface -
+ * Fonera 2.0g (FON2202). It has a USB EHCI controller connected to the
+ * AR2315 PCI bus. IDSEL pin of USB controller is connected to AD[13] line
+ * and IDSEL pin of AR125 is connected to AD[16] line.
+ */
+
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <asm/paccess.h>
+#include <ar231x_platform.h>
+#include <ar231x.h>
+#include <ar2315_regs.h>
+
+/* Arbitrary size of memory region to access the configuration space */
+#define AR2315_PCI_CFG_SIZE 0x00100000
+
+#define AR2315_PCI_HOST_SLOT 3
+#define AR2315_PCI_HOST_DEVID ((0xff18 << 16) | PCI_VENDOR_ID_ATHEROS)
+
+static void __iomem *ar2315_pci_cfg_mem;
+
+static int ar2315_pci_cfg_access(int devfn, int where, int size, u32 *ptr,
+ bool write)
+{
+ int func = PCI_FUNC(devfn);
+ int dev = PCI_SLOT(devfn);
+ u32 addr = (1 << (13 + dev)) | (func << 8) | (where & ~3);
+ u32 mask = 0xffffffff >> 8 * (4 - size);
+ u32 sh = (where & 3) * 8;
+ u32 value, isr;
+
+ /* Prevent access past the remapped area */
+ if (addr >= AR2315_PCI_CFG_SIZE || dev > 18)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ /* Clear pending errors */
+ ar231x_write_reg(AR2315_PCI_ISR, AR2315_PCI_INT_ABORT);
+ /* Select Configuration access */
+ ar231x_mask_reg(AR2315_PCI_MISC_CONFIG, 0, AR2315_PCIMISC_CFG_SEL);
+
+ mb(); /* PCI must see space change before we begin */
+
+ value = __raw_readl(ar2315_pci_cfg_mem + addr);
+
+ isr = ar231x_read_reg(AR2315_PCI_ISR);
+ if (isr & AR2315_PCI_INT_ABORT)
+ goto exit_err;
+
+ if (write) {
+ value = (value & ~(mask << sh)) | *ptr << sh;
+ __raw_writel(value, ar2315_pci_cfg_mem + addr);
+ isr = ar231x_read_reg(AR2315_PCI_ISR);
+ if (isr & AR2315_PCI_INT_ABORT)
+ goto exit_err;
+ } else {
+ *ptr = (value >> sh) & mask;
+ }
+
+ goto exit;
+
+exit_err:
+ ar231x_write_reg(AR2315_PCI_ISR, AR2315_PCI_INT_ABORT);
+ if (!write)
+ *ptr = 0xffffffff;
+
+exit:
+ /* Select Memory access */
+ ar231x_mask_reg(AR2315_PCI_MISC_CONFIG, AR2315_PCIMISC_CFG_SEL, 0);
+
+ return isr & AR2315_PCI_INT_ABORT ? PCIBIOS_DEVICE_NOT_FOUND :
+ PCIBIOS_SUCCESSFUL;
+}
+
+static inline int ar2315_pci_local_cfg_rd(unsigned devfn, int where, u32 *val)
+{
+ return ar2315_pci_cfg_access(devfn, where, sizeof(u32), val, false);
+}
+
+static inline int ar2315_pci_local_cfg_wr(unsigned devfn, int where, u32 val)
+{
+ return ar2315_pci_cfg_access(devfn, where, sizeof(u32), &val, true);
+}
+
+static int ar2315_pci_cfg_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *value)
+{
+ if (PCI_SLOT(devfn) == AR2315_PCI_HOST_SLOT)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return ar2315_pci_cfg_access(devfn, where, size, value, 0);
+}
+
+static int ar2315_pci_cfg_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 value)
+{
+ if (PCI_SLOT(devfn) == AR2315_PCI_HOST_SLOT)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return ar2315_pci_cfg_access(devfn, where, size, &value, 1);
+}
+
+static struct pci_ops ar2315_pci_ops = {
+ .read = ar2315_pci_cfg_read,
+ .write = ar2315_pci_cfg_write,
+};
+
+static struct resource ar2315_mem_resource = {
+ .name = "ar2315-pci-mem",
+ .start = AR2315_PCIEXT,
+ .end = AR2315_PCIEXT + AR2315_PCIEXT_SZ - 1,
+ .flags = IORESOURCE_MEM,
+};
+
+/* PCI controller does not support I/O ports */
+static struct resource ar2315_io_resource = {
+ .name = "ar2315-pci-io",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_IO,
+};
+
+static struct pci_controller ar2315_pci_controller = {
+ .pci_ops = &ar2315_pci_ops,
+ .mem_resource = &ar2315_mem_resource,
+ .io_resource = &ar2315_io_resource,
+ .mem_offset = 0x00000000UL,
+ .io_offset = 0x00000000UL,
+};
+
+static int ar2315_pci_host_setup(void)
+{
+ unsigned devfn = PCI_DEVFN(AR2315_PCI_HOST_SLOT, 0);
+ int res;
+ u32 id;
+
+ res = ar2315_pci_local_cfg_rd(devfn, PCI_VENDOR_ID, &id);
+ if (res != PCIBIOS_SUCCESSFUL || id != AR2315_PCI_HOST_DEVID)
+ return -ENODEV;
+
+ /* Program MBARs */
+ ar2315_pci_local_cfg_wr(devfn, PCI_BASE_ADDRESS_0,
+ AR2315_PCI_HOST_MBAR0);
+ ar2315_pci_local_cfg_wr(devfn, PCI_BASE_ADDRESS_1,
+ AR2315_PCI_HOST_MBAR1);
+ ar2315_pci_local_cfg_wr(devfn, PCI_BASE_ADDRESS_2,
+ AR2315_PCI_HOST_MBAR2);
+
+ /* Run */
+ ar2315_pci_local_cfg_wr(devfn, PCI_COMMAND, PCI_COMMAND_MEMORY |
+ PCI_COMMAND_MASTER | PCI_COMMAND_SPECIAL |
+ PCI_COMMAND_INVALIDATE | PCI_COMMAND_PARITY |
+ PCI_COMMAND_SERR | PCI_COMMAND_FAST_BACK);
+
+ return 0;
+}
+
+static void ar2315_pci_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+ u32 pending = ar231x_read_reg(AR2315_PCI_ISR) &
+ ar231x_read_reg(AR2315_PCI_IMR);
+
+ if (pending & AR2315_PCI_INT_EXT)
+ generic_handle_irq(AR2315_PCI_IRQ_EXT);
+ else if (pending & AR2315_PCI_INT_ABORT)
+ generic_handle_irq(AR2315_PCI_IRQ_ABORT);
+ else
+ spurious_interrupt();
+}
+
+static void ar2315_pci_irq_mask(struct irq_data *d)
+{
+ u32 m = 1 << (d->irq - AR2315_PCI_IRQ_BASE + AR2315_PCI_IRQ_SHIFT);
+
+ ar231x_mask_reg(AR2315_PCI_IMR, m, 0);
+}
+
+static void ar2315_pci_irq_mask_ack(struct irq_data *d)
+{
+ u32 m = 1 << (d->irq - AR2315_PCI_IRQ_BASE + AR2315_PCI_IRQ_SHIFT);
+
+ ar231x_mask_reg(AR2315_PCI_IMR, m, 0);
+ ar231x_write_reg(AR2315_PCI_ISR, m);
+}
+
+static void ar2315_pci_irq_unmask(struct irq_data *d)
+{
+ u32 m = 1 << (d->irq - AR2315_PCI_IRQ_BASE + AR2315_PCI_IRQ_SHIFT);
+
+ ar231x_mask_reg(AR2315_PCI_IMR, 0, m);
+}
+
+static struct irq_chip ar2315_pci_irq_chip = {
+ .name = "AR2315-PCI",
+ .irq_mask = ar2315_pci_irq_mask,
+ .irq_mask_ack = ar2315_pci_irq_mask_ack,
+ .irq_unmask = ar2315_pci_irq_unmask,
+};
+
+static void ar2315_pci_irq_init(void)
+{
+ int i;
+
+ ar231x_mask_reg(AR2315_PCI_IER, AR2315_PCI_IER_ENABLE, 0);
+ ar231x_mask_reg(AR2315_PCI_IMR, (AR2315_PCI_INT_ABORT |
+ AR2315_PCI_INT_EXT), 0);
+
+ for (i = 0; i < AR2315_PCI_IRQ_COUNT; ++i) {
+ int irq = AR2315_PCI_IRQ_BASE + i;
+
+ irq_set_chip_and_handler(irq, &ar2315_pci_irq_chip,
+ handle_level_irq);
+ }
+
+ irq_set_chained_handler(AR2315_IRQ_LCBUS_PCI, ar2315_pci_irq_handler);
+
+ /* Clear any pending Abort or external Interrupts
+ * and enable interrupt processing */
+ ar231x_write_reg(AR2315_PCI_ISR, (AR2315_PCI_INT_ABORT |
+ AR2315_PCI_INT_EXT));
+ ar231x_mask_reg(AR2315_PCI_IER, 0, AR2315_PCI_IER_ENABLE);
+}
+
+static int ar2315_pci_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ u32 reg;
+ int res;
+
+ /* Remap PCI config space */
+ ar2315_pci_cfg_mem = devm_ioremap_nocache(dev, AR2315_PCIEXT,
+ AR2315_PCI_CFG_SIZE);
+ if (!ar2315_pci_cfg_mem) {
+ dev_err(dev, "failed to remap PCI config space\n");
+ return -ENOMEM;
+ }
+
+ /* Reset PCI DMA logic */
+ reg = ar231x_mask_reg(AR2315_RESET, 0, AR2315_RESET_PCIDMA);
+ msleep(20);
+ reg &= ~AR2315_RESET_PCIDMA;
+ ar231x_write_reg(AR2315_RESET, reg);
+ msleep(20);
+
+ ar231x_mask_reg(AR2315_ENDIAN_CTL, 0,
+ AR2315_CONFIG_PCIAHB | AR2315_CONFIG_PCIAHB_BRIDGE);
+
+ ar231x_write_reg(AR2315_PCICLK, AR2315_PCICLK_PLLC_CLKM |
+ (AR2315_PCICLK_IN_FREQ_DIV_6 << AR2315_PCICLK_DIV_S));
+ ar231x_mask_reg(AR2315_AHB_ARB_CTL, 0, AR2315_ARB_PCI);
+ ar231x_mask_reg(AR2315_IF_CTL, AR2315_IF_PCI_CLK_MASK | AR2315_IF_MASK,
+ AR2315_IF_PCI | AR2315_IF_PCI_HOST |
+ AR2315_IF_PCI_INTR | (AR2315_IF_PCI_CLK_OUTPUT_CLK <<
+ AR2315_IF_PCI_CLK_SHIFT));
+
+ /* Reset the PCI bus by setting bits 5-4 in PCI_MCFG */
+ ar231x_mask_reg(AR2315_PCI_MISC_CONFIG, AR2315_PCIMISC_RST_MODE,
+ AR2315_PCIRST_LOW);
+ msleep(100);
+
+ /* Bring the PCI out of reset */
+ ar231x_mask_reg(AR2315_PCI_MISC_CONFIG, AR2315_PCIMISC_RST_MODE,
+ AR2315_PCIRST_HIGH | AR2315_PCICACHE_DIS | 0x8);
+
+ ar231x_write_reg(AR2315_PCI_UNCACHE_CFG,
+ 0x1E | /* 1GB uncached */
+ (1 << 5) | /* Enable uncached */
+ (0x2 << 30) /* Base: 0x80000000 */);
+ ar231x_read_reg(AR2315_PCI_UNCACHE_CFG);
+
+ msleep(500);
+
+ res = ar2315_pci_host_setup();
+ if (res)
+ return res;
+
+ ar2315_pci_irq_init();
+
+ register_pci_controller(&ar2315_pci_controller);
+
+ return 0;
+}
+
+static struct platform_driver ar2315_pci_driver = {
+ .probe = ar2315_pci_probe,
+ .driver = {
+ .name = "ar2315-pci",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init ar2315_pci_init(void)
+{
+ return platform_driver_register(&ar2315_pci_driver);
+}
+arch_initcall(ar2315_pci_init);
+
+int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+ return AR2315_PCI_IRQ_EXT;
+}
+
+int pcibios_plat_dev_init(struct pci_dev *dev)
+{
+ return 0;
+}
--
1.8.1.5
