Re: Merging libata PATA support into the base kernel

[Lee Trager <Lee@PicturesInMotion.net>]

Alan Cox wrote:
> Ar Gwe, 2006-08-18 am 15:22 -0400, ysgrifennodd Lee Trager:
>   
>> Well where in the kernel is the code that disabled HPA on startup? Im
>> new to kernel hacking so if you could point me in the right direction I
>> could try to patch it myself.
>>     
>
> drivers/ide/ide-disk.c
>
> Particularly:
> 	idedisk_check_hpa()
>
> which if you call at the end of the resume sequence for disks ought to
> do the right thing for you
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-ide" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>   
Well I tried to do exactly what you said. All that happens now is that
it does not come out of resume. Below is a patch of the code I tried to
do in case you could like to look at it. Basically I called
idedisk_check_hpa at the end of generic_ide_resume() in drivers/ide/ide.c

diff -Naur linux-2.6.18-rc4-old/drivers/ide/ide-disk.c
linux-2.6.18-rc4/drivers/ide/ide-disk.c
--- linux-2.6.18-rc4-old/drivers/ide/ide-disk.c    2006-08-19
03:49:03.000000000 -0400
+++ linux-2.6.18-rc4/drivers/ide/ide-disk.c    2006-08-19
03:41:33.000000000 -0400
@@ -464,16 +464,6 @@
 }
 
 /*
- * Bits 10 of command_set_1 and cfs_enable_1 must be equal,
- * so on non-buggy drives we need test only one.
- * However, we should also check whether these fields are valid.
- */
-static inline int idedisk_supports_hpa(const struct hd_driveid *id)
-{
-    return (id->command_set_1 & 0x0400) && (id->cfs_enable_1 & 0x0400);
-}
-
-/*
  * The same here.
  */
 static inline int idedisk_supports_lba48(const struct hd_driveid *id)
@@ -482,7 +472,7 @@
            && id->lba_capacity_2;
 }
 
-static void idedisk_check_hpa(ide_drive_t *drive)
+void idedisk_check_hpa(ide_drive_t *drive)
 {
     unsigned long long capacity, set_max;
     int lba48 = idedisk_supports_lba48(drive->id);
@@ -514,6 +504,8 @@
     }
 }
 
+EXPORT_SYMBOL(idedisk_check_hpa);
+
 /*
  * Compute drive->capacity, the full capacity of the drive
  * Called with drive->id != NULL.
diff -Naur linux-2.6.18-rc4-old/drivers/ide/ide.c
linux-2.6.18-rc4/drivers/ide/ide.c
--- linux-2.6.18-rc4-old/drivers/ide/ide.c    2006-08-19
03:49:03.000000000 -0400
+++ linux-2.6.18-rc4/drivers/ide/ide.c    2006-08-19 03:41:33.000000000
-0400
@@ -1242,6 +1242,13 @@
     rqpm.pm_step = ide_pm_state_start_resume;
     rqpm.pm_state = PM_EVENT_ON;
 
+    /* check to see if this is a hard drive
+     * if it is then checkhpa needs to be
+     * disabled */
+    if(drive->media == ide_disk)
+        if(idedisk_supports_hpa(drive->id))
+            idedisk_check_hpa(drive);
+
     return ide_do_drive_cmd(drive, &rq, ide_head_wait);
 }
diff -Naur linux-2.6.18-rc4-old/include/linux/ide.h
linux-2.6.18-rc4/include/linux/ide.h
--- linux-2.6.18-rc4-old/include/linux/ide.h    2006-08-19
03:49:03.000000000 -0400
+++ linux-2.6.18-rc4/include/linux/ide.h    2006-08-19
03:42:53.000000000 -0400
@@ -1377,4 +1377,16 @@
     return dev ? pcibus_to_node(dev->bus) : -1;
 }
 
+extern void idedisk_check_hpa(ide_drive_t *drive);
+
+/*
+ *  * Bits 10 of command_set_1 and cfs_enable_1 must be equal,
+ *   * so on non-buggy drives we need test only one.
+ *    * However, we should also check whether these fields are valid.
+ *     */
+static inline int idedisk_supports_hpa(const struct hd_driveid *id)
+{
+        return (id->command_set_1 & 0x0400) && (id->cfs_enable_1 & 0x0400);
+}
+
 #endif /* _IDE_H */