openwrtv3/target/linux/atheros/patches-3.14/105-ar2315_pci.patch
John Crispin dbdd8906ac atheros: ar2315-pci: rework interrupt handling
Add PCI IRQ controller to facilitate interrupt handling, move interrupts
initialization to the IRQ controller initialization from
pcibios_plat_dev_init() callback.

Also remove odd PCI dev configuration manipulation from pcibios_plat_dev_init()
callback.

Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

SVN-Revision: 42501
2014-09-12 06:53:00 +00:00

372 lines
11 KiB
Diff

--- a/arch/mips/ar231x/Makefile
+++ b/arch/mips/ar231x/Makefile
@@ -14,3 +14,4 @@ obj-$(CONFIG_EARLY_PRINTK) += early_prin
obj-$(CONFIG_ATHEROS_AR5312) += ar5312.o
obj-$(CONFIG_ATHEROS_AR2315) += ar2315.o
+obj-$(CONFIG_ATHEROS_AR2315_PCI) += pci.o
--- /dev/null
+++ b/arch/mips/ar231x/pci.c
@@ -0,0 +1,336 @@
+/*
+ * 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/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>
+#include "devices.h"
+
+#define AR2315_MEM_BASE 0x80800000UL
+#define AR2315_MEM_SIZE 0x00ffffffUL
+#define AR2315_IO_SIZE 0x00007fffUL
+
+#define AR2315_PCI_HOST_SLOT 3
+#define AR2315_PCI_HOST_DEVID ((0xff18 << 16) | PCI_VENDOR_ID_ATHEROS)
+
+static unsigned long configspace;
+
+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 value = 0;
+ int err = 0;
+ u32 addr;
+
+ /* Select Configuration access */
+ ar231x_mask_reg(AR2315_PCI_MISC_CONFIG, 0, AR2315_PCIMISC_CFG_SEL);
+ mb();
+
+ addr = (u32)configspace + (1 << (13 + dev)) + (func << 8) + where;
+ if (size == 1)
+ addr ^= 0x3;
+ else if (size == 2)
+ addr ^= 0x2;
+
+ if (write) {
+ value = *ptr;
+ if (size == 1)
+ err = put_dbe(value, (u8 *)addr);
+ else if (size == 2)
+ err = put_dbe(value, (u16 *)addr);
+ else if (size == 4)
+ err = put_dbe(value, (u32 *)addr);
+ } else {
+ if (size == 1)
+ err = get_dbe(value, (u8 *)addr);
+ else if (size == 2)
+ err = get_dbe(value, (u16 *)addr);
+ else if (size == 4)
+ err = get_dbe(value, (u32 *)addr);
+ if (err)
+ *ptr = 0xffffffff;
+ else
+ *ptr = value;
+ }
+
+ /* Select Memory access */
+ ar231x_mask_reg(AR2315_PCI_MISC_CONFIG, AR2315_PCIMISC_CFG_SEL, 0);
+
+ return err ? 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) != 0) || (PCI_FUNC(devfn) > 2))
+ 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) != 0) || (PCI_FUNC(devfn) > 2))
+ 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_MEM_BASE,
+ .end = AR2315_MEM_BASE + AR2315_MEM_SIZE - AR2315_IO_SIZE - 1 +
+ 0x4000000,
+ .flags = IORESOURCE_MEM,
+};
+
+static struct resource ar2315_io_resource = {
+ .name = "ar2315-pci-io",
+ .start = AR2315_MEM_BASE + AR2315_MEM_SIZE - AR2315_IO_SIZE,
+ .end = AR2315_MEM_BASE + AR2315_MEM_SIZE - 1,
+ .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,
+};
+
+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;
+}
+
+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, HOST_PCI_MBAR0);
+ ar2315_pci_local_cfg_wr(devfn, PCI_BASE_ADDRESS_1, HOST_PCI_MBAR1);
+ ar2315_pci_local_cfg_wr(devfn, PCI_BASE_ADDRESS_2, HOST_PCI_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 __init
+ar2315_pci_init(void)
+{
+ u32 reg;
+ int res;
+
+ if (ar231x_devtype != DEV_TYPE_AR2315)
+ return -ENODEV;
+
+ /* Remap PCI config space */
+ configspace = (unsigned long)ioremap_nocache(AR2315_PCIEXT,
+ 1 * 1024 * 1024);
+ ar2315_pci_controller.io_map_base =
+ (unsigned long)ioremap_nocache(AR2315_MEM_BASE +
+ AR2315_MEM_SIZE, AR2315_IO_SIZE);
+ set_io_port_base(ar2315_pci_controller.io_map_base); /* PCI I/O space*/
+
+ /* 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);
+
+ /* dirty hack - anyone with a datasheet that knows the memory map ? */
+ ioport_resource.start = 0x10000000;
+ ioport_resource.end = 0xffffffff;
+
+ res = ar2315_pci_host_setup();
+ if (res)
+ goto error;
+
+ ar2315_pci_irq_init();
+
+ register_pci_controller(&ar2315_pci_controller);
+
+ return 0;
+
+error:
+ iounmap((void __iomem *)configspace);
+ return res;
+}
+
+arch_initcall(ar2315_pci_init);
--- a/arch/mips/ar231x/Kconfig
+++ b/arch/mips/ar231x/Kconfig
@@ -7,3 +7,10 @@ config ATHEROS_AR2315
bool "Atheros 2315+ support"
depends on ATHEROS_AR231X
default y
+
+config ATHEROS_AR2315_PCI
+ bool "PCI support"
+ depends on ATHEROS_AR2315
+ select HW_HAS_PCI
+ select PCI
+ default y
--- a/arch/mips/ar231x/ar2315.c
+++ b/arch/mips/ar231x/ar2315.c
@@ -104,6 +104,10 @@ ar2315_irq_dispatch(void)
do_IRQ(AR2315_IRQ_WLAN0_INTRS);
else if (pending & CAUSEF_IP4)
do_IRQ(AR2315_IRQ_ENET0_INTRS);
+#ifdef CONFIG_ATHEROS_AR2315_PCI
+ else if (pending & CAUSEF_IP5)
+ do_IRQ(AR2315_IRQ_LCBUS_PCI);
+#endif
else if (pending & CAUSEF_IP2)
do_IRQ(AR2315_IRQ_MISC_INTRS);
else if (pending & CAUSEF_IP7)