[PATCH] ide-cd: Handle strange interrupt on the Intel ESB2

[powerpc.git] / drivers / ide / pci / piix.c

diff --git a/drivers/ide/pci/piix.c b/drivers/ide/pci/piix.c
index eb5bab1..b1e9a8e 100644 (file)
--- a/drivers/ide/pci/piix.c
+++ b/drivers/ide/pci/piix.c
@@ -222,13 +222,15 @@ static void piix_tune_drive (ide_drive_t *drive, u8 pio)
        u16 master_data;
        u8 slave_data;
        static DEFINE_SPINLOCK(tune_lock);
+       int control = 0;
 
                                 /* ISP  RTC */
-       u8 timings[][2] = { { 0, 0 },
-                           { 0, 0 },
-                           { 1, 0 },
-                           { 2, 1 },
-                           { 2, 3 }, };
+       static const u8 timings[][2]= {
+                                       { 0, 0 },
+                                       { 0, 0 },
+                                       { 1, 0 },
+                                       { 2, 1 },
+                                       { 2, 3 }, };
 
        pio = ide_get_best_pio_mode(drive, pio, 5, NULL);
 
@@ -239,19 +241,30 @@ static void piix_tune_drive (ide_drive_t *drive, u8 pio)
         */
        spin_lock_irqsave(&tune_lock, flags);
        pci_read_config_word(dev, master_port, &master_data);
+
+       if (pio >= 2)
+               control |= 1;   /* Programmable timing on */
+       if (drive->media == ide_disk)
+               control |= 4;   /* Prefetch, post write */
+       if (pio >= 3)
+               control |= 2;   /* IORDY */
        if (is_slave) {
                master_data = master_data | 0x4000;
-               if (pio > 1)
+               if (pio > 1) {
                        /* enable PPE, IE and TIME */
-                       master_data = master_data | 0x0070;
+                       master_data = master_data | (control << 4);
+               } else {
+                       master_data &= ~0x0070;
+               }
                pci_read_config_byte(dev, slave_port, &slave_data);
                slave_data = slave_data & (hwif->channel ? 0x0f : 0xf0);
                slave_data = slave_data | (((timings[pio][0] << 2) | timings[pio][1]) << (hwif->channel ? 4 : 0));
        } else {
                master_data = master_data & 0xccf8;
-               if (pio > 1)
+               if (pio > 1) {
                        /* enable PPE, IE and TIME */
-                       master_data = master_data | 0x0007;
+                       master_data = master_data | control;
+               }
                master_data = master_data | (timings[pio][0] << 12) | (timings[pio][1] << 8);
        }
        pci_write_config_word(dev, master_port, master_data);
@@ -492,6 +505,10 @@ static void __devinit init_hwif_piix(ide_hwif_t *hwif)
                /* This is a painful system best to let it self tune for now */
                return;
        }
+       /* ESB2 appears to generate spurious DMA interrupts in PIO mode
+          when in native mode */
+       if (hwif->pci_dev->device == PCI_DEVICE_ID_INTEL_ESB2_18)
+               hwif->atapi_irq_bogon = 1;
 
        hwif->autodma = 0;
        hwif->tuneproc = &piix_tune_drive;