siimage: PIO mode setup fixes (take 2)

* Add sil_tuneproc() wrapper for siimage_tuneproc() which also sets
  PIO mode on the device.

* Add missing ide_get_best_pio_mode() call to sil_tuneproc() so
  "pio" == 255 (autotune) is handled correctly (previously PIO0 was used)
  and "pio" values > 4 && < 255 are filtered to PIO4 (instead of PIO0).

* Add code limiting maximum PIO mode according to the pair device capabilities
  to sil_tuneproc().

* Convert users of config_siimage_chipset_for_pio() to use sil_tune_pio() and
  sil_tuneproc().  This fixes PIO fallback in siimage_config_drive_for_dma() to
  use max PIO mode available instead of PIO4 (config_siimage_chipset_for_pio()
  used wrong arguments for ide_get_best_pio_mode() and as a results always
  tried to set PIO4).

* Remove no longer needed siimage_taskfile_timing()
  and config_siimage_chipset_for_pio().

* Enable ->autotune unconditionally and remove PIO tuning for UDMA/MDMA modes
  from siimage_speedproc()

* Bump driver version.

v2:
* Fix issues noticed by Sergei:
  - correct pair device check
  - trim only taskfile PIO to the slowest of the master/slave
  - enable ->autotune unconditionally and remove PIO tuning for UDMA/MDMA modes
    from siimage_speedproc()
  - add TODO item for IORDY bugs
  - minor cleanups

Reviewed-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 39 insertions, 98 deletions

diff --git a/drivers/ide/pci/siimage.c b/drivers/ide/pci/siimage.c
index 1c3e35487893..5304fc5c616a 100644
--- a/drivers/ide/pci/siimage.c
+++ b/drivers/ide/pci/siimage.c
@@ -1,9 +1,10 @@
 /*
- * linux/drivers/ide/pci/siimage.c              Version 1.12    Mar 10 2007
+ * linux/drivers/ide/pci/siimage.c              Version 1.15    Jun 29 2007
  *
  * Copyright (C) 2001-2002      Andre Hedrick <andre@linux-ide.org>
  * Copyright (C) 2003           Red Hat <alan@redhat.com>
  * Copyright (C) 2007           MontaVista Software, Inc.
+ * Copyright (C) 2007           Bartlomiej Zolnierkiewicz
  *
  *  May be copied or modified under the terms of the GNU General Public License
  *
@@ -31,6 +32,10 @@
  *  unplugging/replugging the virtual CD interface when the DRAC is reset.
  *  This often causes drivers/ide/siimage to panic but is ok with the rather
  *  smarter code in libata.
+ *
+ * TODO:
+ * - IORDY fixes
+ * - VDMA support
  */
 
 #include <linux/types.h>
@@ -160,82 +165,45 @@ out:
 }
 
 /**
- *      siimage_taskfile_timing -       turn timing data to a mode
- *      @hwif: interface to query
- *
- *      Read the timing data for the interface and return the 
- *      mode that is being used.
- */
- 
-static byte siimage_taskfile_timing (ide_hwif_t *hwif)
-{
-        u16 timing      = 0x328a;
-        unsigned long addr = siimage_selreg(hwif, 2);
-
-        if (hwif->mmio)
-                timing = hwif->INW(addr);
-        else
-                pci_read_config_word(hwif->pci_dev, addr, &timing);
-
-        switch (timing) {
-                case 0x10c1:    return 4;
-                case 0x10c3:    return 3;
-                case 0x1104:
-                case 0x1281:    return 2;
-                case 0x2283:    return 1;
-                case 0x328a:
-                default:        return 0;
-        }
-}
-
-/**
- *      simmage_tuneproc        -       tune a drive
+ *      sil_tune_pio    -       tune a drive
  *      @drive: drive to tune
- *      @mode_wanted: the target operating mode
+ *      @pio: the desired PIO mode
  *
  *      Load the timing settings for this device mode into the
  *      controller. If we are in PIO mode 3 or 4 turn on IORDY
  *      monitoring (bit 9). The TF timing is bits 31:16
  */
- 
-static void siimage_tuneproc (ide_drive_t *drive, byte mode_wanted)
+
+static void sil_tune_pio(ide_drive_t *drive, u8 pio)
 {
+        const u16 tf_speed[]    = { 0x328a, 0x2283, 0x1281, 0x10c3, 0x10c1 };
+        const u16 data_speed[]  = { 0x328a, 0x2283, 0x1104, 0x10c3, 0x10c1 };
+
         ide_hwif_t *hwif        = HWIF(drive);
+        ide_drive_t *pair       = &hwif->drives[drive->dn ^ 1];
         u32 speedt              = 0;
         u16 speedp              = 0;
         unsigned long addr      = siimage_seldev(drive, 0x04);
         unsigned long tfaddr    = siimage_selreg(hwif, 0x02);
-        
-        /* cheat for now and use the docs */
-        switch (mode_wanted) {
-        case 4:
-                speedp = 0x10c1;
-                speedt = 0x10c1;
-                break;
-        case 3:
-                speedp = 0x10c3;
-                speedt = 0x10c3;
-                break;
-        case 2:
-                speedp = 0x1104;
-                speedt = 0x1281;
-                break;
-        case 1:
-                speedp = 0x2283;
-                speedt = 0x2283;
-                break;
-        case 0:
-        default:
-                speedp = 0x328a;
-                speedt = 0x328a;
-                break;
+        u8 tf_pio               = pio;
+
+        /* trim *taskfile* PIO to the slowest of the master/slave */
+        if (pair->present) {
+                u8 pair_pio = ide_get_best_pio_mode(pair, 255, 4, NULL);
+
+                if (pair_pio < tf_pio)
+                        tf_pio = pair_pio;
         }
 
+        /* cheat for now and use the docs */
+        speedp = data_speed[pio];
+        speedt = tf_speed[tf_pio];
+
         if (hwif->mmio) {
                 hwif->OUTW(speedp, addr);
                 hwif->OUTW(speedt, tfaddr);
                 /* Now set up IORDY */
-                if(mode_wanted == 3 || mode_wanted == 4)
+                if (pio > 2)
                         hwif->OUTW(hwif->INW(tfaddr-2)|0x200, tfaddr-2);
                 else
                         hwif->OUTW(hwif->INW(tfaddr-2)&~0x200, tfaddr-2);
@@ -245,42 +213,17 @@ static void siimage_tuneproc (ide_drive_t *drive, byte mode_wanted)
                 pci_read_config_word(hwif->pci_dev, tfaddr-2, &speedp);
                 speedp &= ~0x200;
                 /* Set IORDY for mode 3 or 4 */
-                if(mode_wanted == 3 || mode_wanted == 4)
+                if (pio > 2)
                         speedp |= 0x200;
                 pci_write_config_word(hwif->pci_dev, tfaddr-2, speedp);
         }
 }
 
-/**
- *      config_siimage_chipset_for_pio  -       set drive timings
- *      @drive: drive to tune
- *      @speed we want
- *
- *      Compute the best pio mode we can for a given device. Also honour
- *      the timings for the driver when dealing with mixed devices. Some
- *      of this is ugly but its all wrapped up here
- *
- *      The SI680 can also do VDMA - we need to start using that
- *
- *      FIXME: we use the BIOS channel timings to avoid driving the task
- *      files too fast at the disk. We need to compute the master/slave
- *      drive PIO mode properly so that we can up the speed on a hotplug
- *      system.
- */
- 
-static void config_siimage_chipset_for_pio (ide_drive_t *drive, byte set_speed)
+static void sil_tuneproc(ide_drive_t *drive, u8 pio)
 {
-        u8 channel_timings      = siimage_taskfile_timing(HWIF(drive));
-        u8 speed = 0, set_pio   = ide_get_best_pio_mode(drive, 4, 5, NULL);
-
-        /* WARNING PIO timing mess is going to happen b/w devices, argh */
-        if ((channel_timings != set_pio) && (set_pio > channel_timings))
-                set_pio = channel_timings;
-
-        siimage_tuneproc(drive, set_pio);
-        speed = XFER_PIO_0 + set_pio;
-        if (set_speed)
-                (void) ide_config_drive_speed(drive, speed);
+        pio = ide_get_best_pio_mode(drive, pio, 4, NULL);
+        sil_tune_pio(drive, pio);
+        (void)ide_config_drive_speed(drive, XFER_PIO_0 + pio);
 }
 
 /**
@@ -335,7 +278,7 @@ static int siimage_tune_chipset (ide_drive_t *drive, byte xferspeed)
                 case XFER_PIO_2:
                 case XFER_PIO_1:
                 case XFER_PIO_0:
-                        siimage_tuneproc(drive, (speed - XFER_PIO_0));
+                        sil_tune_pio(drive, speed - XFER_PIO_0);
                         mode |= ((unit) ? 0x10 : 0x01);
                         break;
                 case XFER_MW_DMA_2:
@@ -343,7 +286,6 @@ static int siimage_tune_chipset (ide_drive_t *drive, byte xferspeed)
                 case XFER_MW_DMA_0:
                         multi = dma[speed - XFER_MW_DMA_0];
                         mode |= ((unit) ? 0x20 : 0x02);
-                        config_siimage_chipset_for_pio(drive, 0);
                         break;
                 case XFER_UDMA_6:
                 case XFER_UDMA_5:
@@ -356,7 +298,6 @@ static int siimage_tune_chipset (ide_drive_t *drive, byte xferspeed)
                         ultra |= ((scsc) ? (ultra6[speed - XFER_UDMA_0]) :
                                            (ultra5[speed - XFER_UDMA_0]));
                         mode |= ((unit) ? 0x30 : 0x03);
-                        config_siimage_chipset_for_pio(drive, 0);
                         break;
                 default:
                         return 1;
@@ -390,7 +331,7 @@ static int siimage_config_drive_for_dma (ide_drive_t *drive)
                 return 0;
 
         if (ide_use_fast_pio(drive))
-                config_siimage_chipset_for_pio(drive, 1);
+                sil_tuneproc(drive, 255);
 
         return -1;
 }
@@ -961,7 +902,7 @@ static void __devinit init_hwif_siimage(ide_hwif_t *hwif)
         
         hwif->resetproc = &siimage_reset;
         hwif->speedproc = &siimage_tune_chipset;
-        hwif->tuneproc  = &siimage_tuneproc;
+        hwif->tuneproc  = &sil_tuneproc;
         hwif->reset_poll = &siimage_reset_poll;
         hwif->pre_reset = &siimage_pre_reset;
         hwif->udma_filter = &sil_udma_filter;
@@ -976,11 +917,11 @@ static void __devinit init_hwif_siimage(ide_hwif_t *hwif)
                         first = 0;
                 }
         }
-        if (!hwif->dma_base) {
-                hwif->drives[0].autotune = 1;
-                hwif->drives[1].autotune = 1;
+
+        hwif->drives[0].autotune = hwif->drives[1].autotune = 1;
+
+        if (hwif->dma_base == 0)
                 return;
-        }
 
         hwif->ultra_mask = 0x7f;
         hwif->mwdma_mask = 0x07;