[MIPS] Add back support for LASAT platforms

Signed-off-by: Brian Murphy <brian@murphy.dk>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 147 insertions, 0 deletions

diff --git a/arch/mips/pci/ops-nile4.c b/arch/mips/pci/ops-nile4.c
new file mode 100644
index 000000000000..b7f0fb0210f4
--- /dev/null
+++ b/arch/mips/pci/ops-nile4.c
@@ -0,0 +1,147 @@
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <asm/bootinfo.h>
+
+#include <asm/lasat/lasat.h>
+#include <asm/gt64120.h>
+#include <asm/nile4.h>
+
+#define PCI_ACCESS_READ  0
+#define PCI_ACCESS_WRITE 1
+
+#define LO(reg) (reg / 4)
+#define HI(reg) (reg / 4 + 1)
+
+volatile unsigned long *const vrc_pciregs = (void *) Vrc5074_BASE;
+
+static DEFINE_SPINLOCK(nile4_pci_lock);
+
+static int nile4_pcibios_config_access(unsigned char access_type,
+        struct pci_bus *bus, unsigned int devfn, int where, u32 *val)
+{
+        unsigned char busnum = bus->number;
+        u32 adr, mask, err;
+
+        if ((busnum == 0) && (PCI_SLOT(devfn) > 8))
+                /* The addressing scheme chosen leaves room for just
+                 * 8 devices on the first busnum (besides the PCI
+                 * controller itself) */
+                return PCIBIOS_DEVICE_NOT_FOUND;
+
+        if ((busnum == 0) && (devfn == PCI_DEVFN(0, 0))) {
+                /* Access controller registers directly */
+                if (access_type == PCI_ACCESS_WRITE) {
+                        vrc_pciregs[(0x200 + where) >> 2] = *val;
+                } else {
+                        *val = vrc_pciregs[(0x200 + where) >> 2];
+                }
+                return PCIBIOS_SUCCESSFUL;
+        }
+
+        /* Temporarily map PCI Window 1 to config space */
+        mask = vrc_pciregs[LO(NILE4_PCIINIT1)];
+        vrc_pciregs[LO(NILE4_PCIINIT1)] = 0x0000001a | (busnum ? 0x200 : 0);
+
+        /* Clear PCI Error register. This also clears the Error Type
+         * bits in the Control register */
+        vrc_pciregs[LO(NILE4_PCIERR)] = 0;
+        vrc_pciregs[HI(NILE4_PCIERR)] = 0;
+
+        /* Setup address */
+        if (busnum == 0)
+                adr =
+                    KSEG1ADDR(PCI_WINDOW1) +
+                    ((1 << (PCI_SLOT(devfn) + 15)) | (PCI_FUNC(devfn) << 8)
+                     | (where & ~3));
+        else
+                adr = KSEG1ADDR(PCI_WINDOW1) | (busnum << 16) | (devfn << 8) |
+                      (where & ~3);
+
+        if (access_type == PCI_ACCESS_WRITE)
+                *(u32 *) adr = *val;
+        else
+                *val = *(u32 *) adr;
+
+        /* Check for master or target abort */
+        err = (vrc_pciregs[HI(NILE4_PCICTRL)] >> 5) & 0x7;
+
+        /* Restore PCI Window 1 */
+        vrc_pciregs[LO(NILE4_PCIINIT1)] = mask;
+
+        if (err)
+                return PCIBIOS_DEVICE_NOT_FOUND;
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+static int nile4_pcibios_read(struct pci_bus *bus, unsigned int devfn,
+        int where, int size, u32 *val)
+{
+        unsigned long flags;
+        u32 data = 0;
+        int err;
+
+        if ((size == 2) && (where & 1))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+        else if ((size == 4) && (where & 3))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+
+        spin_lock_irqsave(&nile4_pci_lock, flags);
+        err = nile4_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
+                                        &data);
+        spin_unlock_irqrestore(&nile4_pci_lock, flags);
+
+        if (err)
+                return err;
+
+        if (size == 1)
+                *val = (data >> ((where & 3) << 3)) & 0xff;
+        else if (size == 2)
+                *val = (data >> ((where & 3) << 3)) & 0xffff;
+        else
+                *val = data;
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+static int nile4_pcibios_write(struct pci_bus *bus, unsigned int devfn,
+        int where, int size, u32 val)
+{
+        unsigned long flags;
+        u32 data = 0;
+        int err;
+
+        if ((size == 2) && (where & 1))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+        else if ((size == 4) && (where & 3))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+
+        spin_lock_irqsave(&nile4_pci_lock, flags);
+        err = nile4_pcibios_config_access(PCI_ACCESS_READ, bus, devfn, where,
+                                          &data);
+        spin_unlock_irqrestore(&nile4_pci_lock, flags);
+
+        if (err)
+                return err;
+
+        if (size == 1)
+                data = (data & ~(0xff << ((where & 3) << 3))) |
+                    (val << ((where & 3) << 3));
+        else if (size == 2)
+                data = (data & ~(0xffff << ((where & 3) << 3))) |
+                    (val << ((where & 3) << 3));
+        else
+                data = val;
+
+        if (nile4_pcibios_config_access
+            (PCI_ACCESS_WRITE, bus, devfn, where, &data))
+                return -1;
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops nile4_pci_ops = {
+        .read = nile4_pcibios_read,
+        .write = nile4_pcibios_write,
+};