7 files changed, 45 insertions, 39 deletions

diff --git a/drivers/ide/ide-lib.c b/drivers/ide/ide-lib.c
index df29868209f3..92a6c7bcf527 100644
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -291,11 +291,11 @@ u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
         struct hd_driveid* id = drive->id;
         int overridden  = 0;
 
-        if (mode_wanted != 255) {
-                pio_mode = mode_wanted;
-        } else if (!drive->id) {
-                pio_mode = 0;
-        } else if ((pio_mode = ide_scan_pio_blacklist(id->model)) != -1) {
+        if (mode_wanted != 255)
+                return min_t(u8, mode_wanted, max_mode);
+
+        if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0 &&
+            (pio_mode = ide_scan_pio_blacklist(id->model)) != -1) {
                 printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
         } else {
                 pio_mode = id->tPIO;
@@ -324,7 +324,8 @@ u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
                 /*
                  * Conservative "downgrade" for all pre-ATA2 drives
                  */
-                if (pio_mode && pio_mode < 4) {
+                if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_DOWNGRADE) == 0 &&
+                    pio_mode && pio_mode < 4) {
                         pio_mode--;
                         printk(KERN_INFO "%s: applying conservative "
                                          "PIO \"downgrade\"\n", drive->name);
diff --git a/drivers/ide/ide-timing.h b/drivers/ide/ide-timing.h
index 9b5afebafbf4..daffbb9797e1 100644
--- a/drivers/ide/ide-timing.h
+++ b/drivers/ide/ide-timing.h
@@ -106,21 +106,6 @@ static struct ide_timing ide_timing[] = {
 #define XFER_EPIO       0x01
 #define XFER_PIO        0x00
 
-static short ide_find_best_pio_mode(ide_drive_t *drive)
-{
-        struct hd_driveid *id = drive->id;
-        short best = 0;
-
-        /* EIDE PIO modes */
-        if ((id->field_valid & 2) && (id->capability & 8)) {
-                if ((best = (drive->id->eide_pio_modes & 4) ? XFER_PIO_5 :
-                            (drive->id->eide_pio_modes & 2) ? XFER_PIO_4 :
-                            (drive->id->eide_pio_modes & 1) ? XFER_PIO_3 : 0)) return best;
-        }
-
-        return XFER_PIO_0 + min_t(u8, id->tPIO, 2);
-}
-
 static void ide_timing_quantize(struct ide_timing *t, struct ide_timing *q, int T, int UT)
 {
         q->setup   = EZ(t->setup   * 1000,  T);
@@ -210,7 +195,8 @@ static int ide_timing_compute(ide_drive_t *drive, short speed, struct ide_timing
  */
 
         if ((speed & XFER_MODE) != XFER_PIO) {
-                ide_timing_compute(drive, ide_find_best_pio_mode(drive), &p, T, UT);
+                u8 pio = ide_get_best_pio_mode(drive, 255, 5);
+                ide_timing_compute(drive, XFER_PIO_0 + pio, &p, T, UT);
                 ide_timing_merge(&p, t, t, IDE_TIMING_ALL);
         }
 
diff --git a/drivers/ide/ide.c b/drivers/ide/ide.c
index 077fb674a96d..b442b341d52e 100644
--- a/drivers/ide/ide.c
+++ b/drivers/ide/ide.c
@@ -455,6 +455,8 @@ static void ide_hwif_restore(ide_hwif_t *hwif, ide_hwif_t *tmp_hwif)
         hwif->straight8                 = tmp_hwif->straight8;
         hwif->bus_state                 = tmp_hwif->bus_state;
 
+        hwif->host_flags                = tmp_hwif->host_flags;
+
         hwif->atapi_dma                 = tmp_hwif->atapi_dma;
         hwif->ultra_mask                = tmp_hwif->ultra_mask;
         hwif->mwdma_mask                = tmp_hwif->mwdma_mask;
diff --git a/drivers/ide/pci/amd74xx.c b/drivers/ide/pci/amd74xx.c
index 9c3ea90aeb8b..5ed1d485fc7e 100644
--- a/drivers/ide/pci/amd74xx.c
+++ b/drivers/ide/pci/amd74xx.c
@@ -1,5 +1,5 @@
 /*
- * Version 2.20
+ * Version 2.21
  *
  * AMD 755/756/766/8111 and nVidia nForce/2/2s/3/3s/CK804/MCP04
  * IDE driver for Linux.
@@ -272,10 +272,8 @@ static int amd_set_drive(ide_drive_t *drive, u8 speed)
 
 static void amd74xx_tune_drive(ide_drive_t *drive, u8 pio)
 {
-        if (pio == 255) {
-                amd_set_drive(drive, ide_find_best_pio_mode(drive));
-                return;
-        }
+        if (pio == 255)
+                pio = ide_get_best_pio_mode(drive, 255, 5);
 
         amd_set_drive(drive, XFER_PIO_0 + min_t(byte, pio, 5));
 }
@@ -284,12 +282,14 @@ static int amd74xx_ide_dma_check(ide_drive_t *drive)
 {
         u8 speed = ide_max_dma_mode(drive);
 
-        if (speed == 0)
-                speed = ide_find_best_pio_mode(drive);
+        if (speed == 0) {
+                amd74xx_tune_drive(drive, 255);
+                return -1;
+        }
 
         amd_set_drive(drive, speed);
 
-        if (drive->autodma && (speed & XFER_MODE) != XFER_PIO)
+        if (drive->autodma)
                 return 0;
 
         return -1;
@@ -451,6 +451,8 @@ static void __devinit init_hwif_amd74xx(ide_hwif_t *hwif)
                 .autodma        = AUTODMA,                              \
                 .enablebits     = {{0x40,0x02,0x02}, {0x40,0x01,0x01}}, \
                 .bootable       = ON_BOARD,                             \
+                .host_flags     = IDE_HFLAG_PIO_NO_BLACKLIST            \
+                                | IDE_HFLAG_PIO_NO_DOWNGRADE,           \
         }
 
 #define DECLARE_NV_DEV(name_str)                                        \
@@ -461,6 +463,8 @@ static void __devinit init_hwif_amd74xx(ide_hwif_t *hwif)
                 .autodma        = AUTODMA,                              \
                 .enablebits     = {{0x50,0x02,0x02}, {0x50,0x01,0x01}}, \
                 .bootable       = ON_BOARD,                             \
+                .host_flags     = IDE_HFLAG_PIO_NO_BLACKLIST            \
+                                | IDE_HFLAG_PIO_NO_DOWNGRADE,           \
         }
 
 static ide_pci_device_t amd74xx_chipsets[] __devinitdata = {
diff --git a/drivers/ide/pci/via82cxxx.c b/drivers/ide/pci/via82cxxx.c
index bfc9b67f8c92..b107ee3588f7 100644
--- a/drivers/ide/pci/via82cxxx.c
+++ b/drivers/ide/pci/via82cxxx.c
@@ -1,6 +1,6 @@
 /*
  *
- * Version 3.45
+ * Version 3.46
  *
  * VIA IDE driver for Linux. Supported southbridges:
  *
@@ -203,10 +203,8 @@ static int via_set_drive(ide_drive_t *drive, u8 speed)
 
 static void via82cxxx_tune_drive(ide_drive_t *drive, u8 pio)
 {
-        if (pio == 255) {
-                via_set_drive(drive, ide_find_best_pio_mode(drive));
-                return;
-        }
+        if (pio == 255)
+                pio = ide_get_best_pio_mode(drive, 255, 5);
 
         via_set_drive(drive, XFER_PIO_0 + min_t(u8, pio, 5));
 }
@@ -223,12 +221,14 @@ static int via82cxxx_ide_dma_check (ide_drive_t *drive)
 {
         u8 speed = ide_max_dma_mode(drive);
 
-        if (speed == 0)
-                speed = ide_find_best_pio_mode(drive);
+        if (speed == 0) {
+                via82cxxx_tune_drive(drive, 255);
+                return -1;
+        }
 
         via_set_drive(drive, speed);
 
-        if (drive->autodma && (speed & XFER_MODE) != XFER_PIO)
+        if (drive->autodma)
                 return 0;
 
         return -1;
@@ -500,7 +500,9 @@ static ide_pci_device_t via82cxxx_chipsets[] __devinitdata = {
                 .init_hwif      = init_hwif_via82cxxx,
                 .autodma        = NOAUTODMA,
                 .enablebits     = {{0x40,0x02,0x02}, {0x40,0x01,0x01}},
-                .bootable       = ON_BOARD
+                .bootable       = ON_BOARD,
+                .host_flags     = IDE_HFLAG_PIO_NO_BLACKLIST
+                                | IDE_HFLAG_PIO_NO_DOWNGRADE,
         },{     /* 1 */
                 .name           = "VP_IDE",
                 .init_chipset   = init_chipset_via82cxxx,
@@ -508,6 +510,8 @@ static ide_pci_device_t via82cxxx_chipsets[] __devinitdata = {
                 .autodma        = AUTODMA,
                 .enablebits     = {{0x00,0x00,0x00}, {0x00,0x00,0x00}},
                 .bootable       = ON_BOARD,
+                .host_flags     = IDE_HFLAG_PIO_NO_BLACKLIST
+                                | IDE_HFLAG_PIO_NO_DOWNGRADE,
         }
 };
 
diff --git a/drivers/ide/setup-pci.c b/drivers/ide/setup-pci.c
index bfe1f4e59597..e9f3267456e2 100644
--- a/drivers/ide/setup-pci.c
+++ b/drivers/ide/setup-pci.c
@@ -613,6 +613,8 @@ void ide_pci_setup_ports(struct pci_dev *dev, ide_pci_device_t *d, int pciirq, a
                 else
                         ide_hwif_setup_dma(dev, d, hwif);
 bypass_legacy_dma:
+                hwif->host_flags = d->host_flags;
+
                 if (d->init_hwif)
                         /* Call chipset-specific routine
                          * for each enabled hwif
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 14a87f619d17..9f72f6e0c954 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -681,6 +681,8 @@ typedef struct hwif_s {
         u8 straight8;   /* Alan's straight 8 check */
         u8 bus_state;   /* power state of the IDE bus */
 
+        u8 host_flags;
+
         u8 atapi_dma;   /* host supports atapi_dma */
         u8 ultra_mask;
         u8 mwdma_mask;
@@ -1245,7 +1247,12 @@ typedef struct ide_pci_enablebit_s {
 enum {
         /* Uses ISA control ports not PCI ones. */
         IDE_HFLAG_ISA_PORTS             = (1 << 0),
+        /* single port device */
         IDE_HFLAG_SINGLE                = (1 << 1),
+        /* don't use legacy PIO blacklist */
+        IDE_HFLAG_PIO_NO_BLACKLIST      = (1 << 2),
+        /* don't use conservative PIO "downgrade" */
+        IDE_HFLAG_PIO_NO_DOWNGRADE      = (1 << 3),
 };
 
 typedef struct ide_pci_device_s {