sh: pci: Rework SH7780 host controller detection.

This reworks how the host controller is probed, and makes it a bit more
verbose in the event a new type of controller is detected. Additionally,
we also log the revision information.

This now uses the proper access sizes for the vendor/device registers,
rather than relying on a larger access that encapsulated both of them.
Not all devices support 32-bit read cycles for these registers.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 26 insertions, 21 deletions

diff --git a/arch/sh/drivers/pci/pci-sh7780.c b/arch/sh/drivers/pci/pci-sh7780.c
index 7f4f5903754..63b5151e9aa 100644
--- a/arch/sh/drivers/pci/pci-sh7780.c
+++ b/arch/sh/drivers/pci/pci-sh7780.c
@@ -34,33 +34,39 @@
 int __init sh7780_pci_init(struct pci_channel *chan)
 {
         unsigned int id;
-        int ret, match = 0;
+        const char *type = NULL;
+        int ret;
 
-        pr_debug("PCI: Starting intialization.\n");
+        printk(KERN_NOTICE "PCI: Starting intialization.\n");
 
         chan->reg_base = 0xfe040000;
         chan->io_base = 0xfe200000;
 
-        ctrl_outl(0x00000001, SH7780_PCI_VCR2); /* Enable PCIC */
-
-        /* check for SH7780/SH7780R hardware */
-        id = pci_read_reg(chan, SH7780_PCIVID);
-        if ((id & 0xffff) == SH7780_VENDOR_ID) {
-                switch ((id >> 16) & 0xffff) {
-                case SH7763_DEVICE_ID:
-                case SH7780_DEVICE_ID:
-                case SH7781_DEVICE_ID:
-                case SH7785_DEVICE_ID:
-                        match = 1;
-                        break;
-                }
-        }
+        /* Enable CPU access to the PCIC registers. */
+        __raw_writel(PCIECR_ENBL, PCIECR);
 
-        if (unlikely(!match)) {
-                printk(KERN_ERR "PCI: This is not an SH7780 (%x)\n", id);
+        id = __raw_readw(chan->reg_base + SH7780_PCIVID);
+        if (id != SH7780_VENDOR_ID) {
+                printk(KERN_ERR "PCI: Unknown vendor ID 0x%04x.\n", id);
                 return -ENODEV;
         }
 
+        id = __raw_readw(chan->reg_base + SH7780_PCIDID);
+        type = (id == SH7763_DEVICE_ID) ? "SH7763" :
+               (id == SH7780_DEVICE_ID) ? "SH7780" :
+               (id == SH7781_DEVICE_ID) ? "SH7781" :
+               (id == SH7785_DEVICE_ID) ? "SH7785" :
+                                          NULL;
+        if (unlikely(!type)) {
+                printk(KERN_ERR "PCI: Found an unsupported Renesas host "
+                       "controller, device id 0x%04x.\n", id);
+                return -EINVAL;
+        }
+
+        printk(KERN_NOTICE "PCI: Found a Renesas %s host "
+               "controller, revision %d.\n", type,
+               __raw_readb(chan->reg_base + SH7780_PCIRID));
+
         if ((ret = sh4_pci_check_direct(chan)) != 0)
                 return ret;
 
diff --git a/arch/sh/drivers/pci/pci-sh7780.h b/arch/sh/drivers/pci/pci-sh7780.h
index fffcf1dcfed..213f1d8c9ca 100644
--- a/arch/sh/drivers/pci/pci-sh7780.h
+++ b/arch/sh/drivers/pci/pci-sh7780.h
@@ -20,9 +20,8 @@
 #define SH7785_DEVICE_ID        0x0007
 
 /* SH7780 Control Registers */
-#define SH7780_PCI_VCR0         0xFE000000
-#define SH7780_PCI_VCR1         0xFE000004
-#define SH7780_PCI_VCR2         0xFE000008
+#define PCIECR                  0xFE000008
+#define PCIECR_ENBL             0x01
 
 /* SH7780 Specific Values */
 #define SH7780_PCI_CONFIG_BASE  0xFD000000      /* Config space base addr */