---

yaml
---
r: 15858
b: refs/heads/master
c: d96212e
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fe79e683ccdb29c13b3e0d18507474b4e2d9aab6
+refs/heads/master: d96212ed87d032d2d830e265aae14038dc1f8ad8

trunk/drivers/scsi/ata_piix.c

@@ -37,6 +37,49 @@
  *
  *  Hardware documentation available at http://developer.intel.com/
  *
+ * Documentation
+ *	Publically available from Intel web site. Errata documentation
+ * is also publically available. As an aide to anyone hacking on this
+ * driver the list of errata that are relevant is below.going back to
+ * PIIX4. Older device documentation is now a bit tricky to find.
+ *
+ * The chipsets all follow very much the same design. The orginal Triton
+ * series chipsets do _not_ support independant device timings, but this
+ * is fixed in Triton II. With the odd mobile exception the chips then
+ * change little except in gaining more modes until SATA arrives. This
+ * driver supports only the chips with independant timing (that is those
+ * with SITRE and the 0x44 timing register). See pata_oldpiix and pata_mpiix
+ * for the early chip drivers.
+ *
+ * Errata of note:
+ *
+ * Unfixable
+ *	PIIX4    errata #9	- Only on ultra obscure hw
+ *	ICH3	 errata #13     - Not observed to affect real hw
+ *				  by Intel
+ *
+ * Things we must deal with
+ *	PIIX4	errata #10	- BM IDE hang with non UDMA
+ *				  (must stop/start dma to recover)
+ *	440MX   errata #15	- As PIIX4 errata #10
+ *	PIIX4	errata #15	- Must not read control registers
+ * 				  during a PIO transfer
+ *	440MX   errata #13	- As PIIX4 errata #15
+ *	ICH2	errata #21	- DMA mode 0 doesn't work right
+ *	ICH0/1  errata #55	- As ICH2 errata #21
+ *	ICH2	spec c #9	- Extra operations needed to handle
+ *				  drive hotswap [NOT YET SUPPORTED]
+ *	ICH2    spec c #20	- IDE PRD must not cross a 64K boundary
+ *				  and must be dword aligned
+ *	ICH2    spec c #24	- UDMA mode 4,5 t85/86 should be 6ns not 3.3
+ *
+ * Should have been BIOS fixed:
+ *	450NX:	errata #19	- DMA hangs on old 450NX
+ *	450NX:  errata #20	- DMA hangs on old 450NX
+ *	450NX:  errata #25	- Corruption with DMA on old 450NX
+ *	ICH3    errata #15      - IDE deadlock under high load
+ *				  (BIOS must set dev 31 fn 0 bit 23)
+ *	ICH3	errata #18	- Don't use native mode
  */
 
 #include <linux/kernel.h>