[ARM] 4577/1: ITE 8152 PCI bridge support

This patch provides driver for ITE 8152 PCI bridge.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 387 insertions, 0 deletions

diff --git a/arch/arm/common/it8152.c b/arch/arm/common/it8152.c
new file mode 100644
index 000000000000..c03de9bfd76b
--- /dev/null
+++ b/arch/arm/common/it8152.c
@@ -0,0 +1,387 @@
+/*
+ * linux/arch/arm/common/it8152.c
+ *
+ * Copyright Compulab Ltd, 2002-2007
+ * Mike Rapoport <mike@compulab.co.il>
+ *
+ * The DMA bouncing part is taken from arch/arm/mach-ixp4xx/common-pci.c
+ * (see this file for respective copyrights)
+ *
+ * Thanks to Guennadi Liakhovetski <gl@dsa-ac.de> for IRQ enumberation
+ * and demux code.
+ *
+ * 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/sched.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/ptrace.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <asm/mach/pci.h>
+#include <asm/hardware/it8152.h>
+
+#define MAX_SLOTS               21
+
+static void it8152_mask_irq(unsigned int irq)
+{
+       if (irq >= IT8152_LD_IRQ(0)) {
+               __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) |
+                            (1 << (irq - IT8152_LD_IRQ(0)))),
+                            IT8152_INTC_LDCNIMR);
+       } else if (irq >= IT8152_LP_IRQ(0)) {
+               __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) |
+                            (1 << (irq - IT8152_LP_IRQ(0)))),
+                            IT8152_INTC_LPCNIMR);
+       } else if (irq >= IT8152_PD_IRQ(0)) {
+               __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) |
+                            (1 << (irq - IT8152_PD_IRQ(0)))),
+                            IT8152_INTC_PDCNIMR);
+       }
+}
+
+static void it8152_unmask_irq(unsigned int irq)
+{
+       if (irq >= IT8152_LD_IRQ(0)) {
+               __raw_writel((__raw_readl(IT8152_INTC_LDCNIMR) &
+                             ~(1 << (irq - IT8152_LD_IRQ(0)))),
+                            IT8152_INTC_LDCNIMR);
+       } else if (irq >= IT8152_LP_IRQ(0)) {
+               __raw_writel((__raw_readl(IT8152_INTC_LPCNIMR) &
+                             ~(1 << (irq - IT8152_LP_IRQ(0)))),
+                            IT8152_INTC_LPCNIMR);
+       } else if (irq >= IT8152_PD_IRQ(0)) {
+               __raw_writel((__raw_readl(IT8152_INTC_PDCNIMR) &
+                             ~(1 << (irq - IT8152_PD_IRQ(0)))),
+                            IT8152_INTC_PDCNIMR);
+       }
+}
+
+static inline void it8152_irq(int irq)
+{
+        struct irq_desc *desc;
+
+        printk(KERN_DEBUG "===> %s: irq=%d\n", __FUNCTION__, irq);
+
+        desc = irq_desc + irq;
+        desc_handle_irq(irq, desc);
+}
+
+static struct irq_chip it8152_irq_chip = {
+        .name           = "it8152",
+        .ack            = it8152_mask_irq,
+        .mask           = it8152_mask_irq,
+        .unmask         = it8152_unmask_irq,
+};
+
+void it8152_init_irq(void)
+{
+        int irq;
+
+        __raw_writel((0xffff), IT8152_INTC_PDCNIMR);
+        __raw_writel((0), IT8152_INTC_PDCNIRR);
+        __raw_writel((0xffff), IT8152_INTC_LPCNIMR);
+        __raw_writel((0), IT8152_INTC_LPCNIRR);
+        __raw_writel((0xffff), IT8152_INTC_LDCNIMR);
+        __raw_writel((0), IT8152_INTC_LDCNIRR);
+
+        for (irq = IT8152_IRQ(0); irq <= IT8152_LAST_IRQ; irq++) {
+                set_irq_chip(irq, &it8152_irq_chip);
+                set_irq_handler(irq, handle_level_irq);
+                set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+        }
+}
+
+void it8152_irq_demux(unsigned int irq, struct irq_desc *desc)
+{
+       int bits_pd, bits_lp, bits_ld;
+       int i;
+
+       printk(KERN_DEBUG "=> %s: irq = %d\n", __FUNCTION__, irq);
+
+       while (1) {
+               /* Read all */
+               bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
+               bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
+               bits_ld = __raw_readl(IT8152_INTC_LDCNIRR);
+
+               /* Ack */
+               __raw_writel((~bits_pd), IT8152_INTC_PDCNIRR);
+               __raw_writel((~bits_lp), IT8152_INTC_LPCNIRR);
+               __raw_writel((~bits_ld), IT8152_INTC_LDCNIRR);
+
+               if (!(bits_ld | bits_lp | bits_pd)) {
+                       /* Re-read to guarantee, that there was a moment of
+                          time, when they all three were 0. */
+                       bits_pd = __raw_readl(IT8152_INTC_PDCNIRR);
+                       bits_lp = __raw_readl(IT8152_INTC_LPCNIRR);
+                       if (!(bits_ld | bits_lp | bits_pd))
+                               return;
+               }
+
+               bits_pd &= ((1 << IT8152_PD_IRQ_COUNT) - 1);
+               while (bits_pd) {
+                       i = __ffs(bits_pd);
+                       it8152_irq(IT8152_PD_IRQ(i));
+                       bits_pd &= ~(1 << i);
+               }
+
+               bits_lp &= ((1 << IT8152_LP_IRQ_COUNT) - 1);
+               while (bits_lp) {
+                       i = __ffs(bits_pd);
+                       it8152_irq(IT8152_LP_IRQ(i));
+                       bits_lp &= ~(1 << i);
+               }
+
+               bits_ld &= ((1 << IT8152_LD_IRQ_COUNT) - 1);
+               while (bits_ld) {
+                       i = __ffs(bits_pd);
+                       it8152_irq(IT8152_LD_IRQ(i));
+                       bits_ld &= ~(1 << i);
+               }
+       }
+}
+
+/* mapping for on-chip devices */
+int __init it8152_pci_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
+{
+        if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
+            (dev->device == PCI_DEVICE_ID_ITE_8152)) {
+                if ((dev->class >> 8) == PCI_CLASS_MULTIMEDIA_AUDIO)
+                        return IT8152_AUDIO_INT;
+                if ((dev->class >> 8) == PCI_CLASS_SERIAL_USB)
+                        return IT8152_USB_INT;
+                if ((dev->class >> 8) == PCI_CLASS_SYSTEM_DMA)
+                        return IT8152_CDMA_INT;
+        }
+
+        return 0;
+}
+
+static unsigned long it8152_pci_dev_base_address(struct pci_bus *bus,
+                                                 unsigned int devfn)
+{
+        unsigned long addr = 0;
+
+        if (bus->number == 0) {
+                        if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
+                                addr = (devfn << 8);
+        } else
+                addr = (bus->number << 16) | (devfn << 8);
+
+        return addr;
+}
+
+static int it8152_pci_read_config(struct pci_bus *bus,
+                                  unsigned int devfn, int where,
+                                  int size, u32 *value)
+{
+        unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
+        u32 v;
+        int shift;
+
+        shift = (where & 3);
+
+        __raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
+        v = (__raw_readl(IT8152_PCI_CFG_DATA)  >> (8 * (shift)));
+
+        *value = v;
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+static int it8152_pci_write_config(struct pci_bus *bus,
+                                   unsigned int devfn, int where,
+                                   int size, u32 value)
+{
+        unsigned long addr = it8152_pci_dev_base_address(bus, devfn);
+        u32 v, vtemp, mask = 0;
+        int shift;
+
+        if (size == 1)
+                mask = 0xff;
+        if (size == 2)
+                mask = 0xffff;
+
+        shift = (where & 3);
+
+        __raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
+        vtemp = __raw_readl(IT8152_PCI_CFG_DATA);
+
+        if (mask)
+                vtemp &= ~(mask << (8 * shift));
+        else
+                vtemp = 0;
+
+        v = (value << (8 * shift));
+        __raw_writel((addr + where), IT8152_PCI_CFG_ADDR);
+        __raw_writel((v | vtemp), IT8152_PCI_CFG_DATA);
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops it8152_ops = {
+        .read = it8152_pci_read_config,
+        .write = it8152_pci_write_config,
+};
+
+static struct resource it8152_io = {
+        .name   = "IT8152 PCI I/O region",
+        .flags  = IORESOURCE_IO,
+};
+
+static struct resource it8152_mem = {
+        .name   = "IT8152 PCI memory region",
+        .start  = 0x10000000,
+        .end    = 0x13e00000,
+        .flags  = IORESOURCE_MEM,
+};
+
+/*
+ * The following functions are needed for DMA bouncing.
+ * ITE8152 chip can addrees up to 64MByte, so all the devices
+ * connected to ITE8152 (PCI and USB) should have limited DMA window
+ */
+
+/*
+ * Setup DMA mask to 64MB on devices connected to ITE8152. Ignore all
+ * other devices.
+ */
+static int it8152_pci_platform_notify(struct device *dev)
+{
+        if (dev->bus == &pci_bus_type) {
+                if (dev->dma_mask)
+                        *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
+                dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
+                dmabounce_register_dev(dev, 2048, 4096);
+        }
+        return 0;
+}
+
+static int it8152_pci_platform_notify_remove(struct device *dev)
+{
+        if (dev->bus == &pci_bus_type)
+                dmabounce_unregister_dev(dev);
+
+        return 0;
+}
+
+int dma_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
+{
+        dev_dbg(dev, "%s: dma_addr %08x, size %08x\n",
+                __FUNCTION__, dma_addr, size);
+        return (dev->bus == &pci_bus_type) &&
+                ((dma_addr + size - PHYS_OFFSET) >= SZ_64M);
+}
+
+/*
+ * We override these so we properly do dmabounce otherwise drivers
+ * are able to set the dma_mask to 0xffffffff and we can no longer
+ * trap bounces. :(
+ *
+ * We just return true on everyhing except for < 64MB in which case
+ * we will fail miseralby and die since we can't handle that case.
+ */
+int pci_set_dma_mask(struct pci_dev *dev, u64 mask)
+{
+        printk(KERN_DEBUG "%s: %s %llx\n",
+               __FUNCTION__, dev->dev.bus_id, mask);
+        if (mask >= PHYS_OFFSET + SZ_64M - 1)
+                return 0;
+
+        return -EIO;
+}
+
+int
+pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
+{
+        printk(KERN_DEBUG "%s: %s %llx\n",
+               __FUNCTION__, dev->dev.bus_id, mask);
+        if (mask >= PHYS_OFFSET + SZ_64M - 1)
+                return 0;
+
+        return -EIO;
+}
+
+int __init it8152_pci_setup(int nr, struct pci_sys_data *sys)
+{
+        it8152_io.start = IT8152_IO_BASE + 0x12000;
+        it8152_io.end   = IT8152_IO_BASE + 0x12000 + 0x100000;
+
+        sys->mem_offset = 0x10000000;
+        sys->io_offset  = IT8152_IO_BASE;
+
+        if (request_resource(&ioport_resource, &it8152_io)) {
+                printk(KERN_ERR "PCI: unable to allocate IO region\n");
+                goto err0;
+        }
+        if (request_resource(&iomem_resource, &it8152_mem)) {
+                printk(KERN_ERR "PCI: unable to allocate memory region\n");
+                goto err1;
+        }
+
+        sys->resource[0] = &it8152_io;
+        sys->resource[1] = &it8152_mem;
+
+        if (platform_notify || platform_notify_remove) {
+                printk(KERN_ERR "PCI: Can't use platform_notify\n");
+                goto err2;
+        }
+
+        platform_notify = it8152_pci_platform_notify;
+        platform_notify_remove = it8152_pci_platform_notify_remove;
+
+        return 1;
+
+err2:
+        release_resource(&it8152_io);
+err1:
+        release_resource(&it8152_mem);
+err0:
+        return -EBUSY;
+}
+
+/*
+ * If we set up a device for bus mastering, we need to check the latency
+ * timer as we don't have even crappy BIOSes to set it properly.
+ * The implementation is from arch/i386/pci/i386.c
+ */
+unsigned int pcibios_max_latency = 255;
+
+void pcibios_set_master(struct pci_dev *dev)
+{
+        u8 lat;
+
+        /* no need to update on-chip OHCI controller */
+        if ((dev->vendor == PCI_VENDOR_ID_ITE) &&
+            (dev->device == PCI_DEVICE_ID_ITE_8152) &&
+            ((dev->class >> 8) == PCI_CLASS_SERIAL_USB))
+                return;
+
+        pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
+        if (lat < 16)
+                lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
+        else if (lat > pcibios_max_latency)
+                lat = pcibios_max_latency;
+        else
+                return;
+        printk(KERN_DEBUG "PCI: Setting latency timer of device %s to %d\n",
+               pci_name(dev), lat);
+        pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
+}
+
+
+struct pci_bus * __init it8152_pci_scan_bus(int nr, struct pci_sys_data *sys)
+{
+        return pci_scan_bus(nr, &it8152_ops, sys);
+}
+