[PATCH] advertise correct IDE mode on Pegasos2

[Olaf Hering <olaf@aepfle.de>]

The built-in IDE controller is configured in legacy mode,
but the PCI registers advertise native mode.
Force the PCI class into legacy mode. This allows pata_via to access
two drives.
The Pegasos specific irq enforcement in the via82cxxx driver
can be removed.

Tested on Pegasos2 with firmware version 20040810, and two IDE disks.


Signed-off-by: Olaf Hering <olaf@aepfle.de>

---
 arch/powerpc/kernel/prom_init.c   |   11 ++++++++---
 arch/powerpc/platforms/chrp/pci.c |   28 ++++++++++++++++++++++++++++
 drivers/ide/pci/via82cxxx.c       |    7 -------
 3 files changed, 36 insertions(+), 10 deletions(-)

--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -2041,6 +2041,7 @@ static void __init fixup_device_tree_map
 /*
  * Pegasos and BriQ lacks the "ranges" property in the isa node
  * Pegasos needs decimal IRQ 14/15, not hexadecimal
+ * Pegasos has the IDE configured in legacy mode, but advertised as native
  */
 static void __init fixup_device_tree_chrp(void)
 {
@@ -2078,9 +2079,13 @@ static void __init fixup_device_tree_chr
 		prom_printf("Fixing up IDE interrupt on Pegasos...\n");
 		prop[0] = 14;
 		prop[1] = 0x0;
-		prop[2] = 15;
-		prop[3] = 0x0;
-		prom_setprop(ph, name, "interrupts", prop, 4*sizeof(u32));
+		prom_setprop(ph, name, "interrupts", prop, 2*sizeof(u32));
+		prom_printf("Fixing up IDE class-code on Pegasos...\n");
+		rc = prom_getprop(ph, "class-code", prop, sizeof(u32));
+		if (rc == sizeof(u32)) {
+			prop[0] &= ~0x5;
+			prom_setprop(ph, name, "class-code", prop, sizeof(u32));
+		}
 	}
 }
 #else
--- a/arch/powerpc/platforms/chrp/pci.c
+++ b/arch/powerpc/platforms/chrp/pci.c
@@ -338,3 +338,31 @@ void chrp_pci_fixup_winbond_ata(struct p
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_WINBOND, PCI_DEVICE_ID_WINBOND_82C105,
 		chrp_pci_fixup_winbond_ata);
+
+/* Pegasos2 firmware version 20040810 configures the built-in IDE controller
+ * in legacy mode, but sets the PCI registers to PCI native mode.
+ * The chip can only operate in legacy mode, so force the PCI class into legacy
+ * mode as well. The same fixup must be done to the class-code property in
+ * the IDE node /pci@80000000/ide@C,1
+ */
+static void chrp_pci_fixup_vt8231_ata(struct pci_dev *viaide)
+{
+	u8 progif;
+	struct pci_dev *viaisa;
+
+	if (!machine_is(chrp) || _chrp_type != _CHRP_Pegasos)
+		return;
+	if (viaide->irq != 14)
+		return;
+
+	viaisa = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231, NULL);
+	if (!viaisa)
+		return;
+	printk("Fixing VIA IDE, force legacy mode on '%s'\n", viaide->dev.bus_id);
+
+	pci_read_config_byte(viaide, PCI_CLASS_PROG, &progif);
+	pci_write_config_byte(viaide, PCI_CLASS_PROG, progif & ~0x5);
+
+	pci_dev_put(viaisa);
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_1, chrp_pci_fixup_vt8231_ata);
--- a/drivers/ide/pci/via82cxxx.c
+++ b/drivers/ide/pci/via82cxxx.c
@@ -436,13 +436,6 @@ static void __devinit init_hwif_via82cxx
 	hwif->tuneproc = &via82cxxx_tune_drive;
 	hwif->speedproc = &via_set_drive;
 
-
-#ifdef CONFIG_PPC_CHRP
-	if(machine_is(chrp) && _chrp_type == _CHRP_Pegasos) {
-		hwif->irq = hwif->channel ? 15 : 14;
-	}
-#endif
-
 	for (i = 0; i < 2; i++) {
 		hwif->drives[i].io_32bit = 1;
 		hwif->drives[i].unmask = (vdev->via_config->flags & VIA_NO_UNMASK) ? 0 : 1;