(cc:ing linuxppc-dev) On Tue, 26 Jun 2007 13:43:15 +0800, Albert Lee wrote: > Recently the PLL input clock of pata_pdc2027x is sometimes detected > higer than expected (e.g. 20.027 MHz compared to 16.714 MHz). > It seems sometimes the mdelay() function is not as precise as it > used to be. Per Alan's advice, HT or power management might affect > the precision of mdelay(). > > This patch calls gettimeofday() to mesure the time elapsed and > calculate the PLL input clock accordingly. Unfortunately this breaks pata_pdc2027x on my PowerMac G3: --- dmesg-2.6.22-rc5 2007-06-23 20:45:45.000000000 +0200 +++ dmesg-2.6.22 2007-07-10 00:39:51.000000000 +0200 @@ -1,6 +1,6 @@ Using PowerMac machine description Total memory = 768MB; using 2048kB for hash table (at cfe00000) -Linux version 2.6.22-rc5 (mikpe@eisbock) (gcc version 4.2.0) #1 Sat Jun 23 20:38:48 CEST 2007 +Linux version 2.6.22 (mikpe@eisbock) (gcc version 4.2.0) #1 Tue Jul 10 00:29:58 CEST 2007 Found a Heathrow mac-io controller, rev: 1, mapped at 0xfdf80000 PowerMac motherboard: PowerMac G3 (Gossamer) Entering add_active_range(0, 0, 196608) 0 entries of 256 used @@ -32,7 +32,7 @@ console handover: boot [udbg0] -> real [tty0] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes) Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) -Memory: 771456k/786432k available (2344k kernel code, 14560k reserved, 116k data, 94k bss, 148k init) +Memory: 771584k/786432k available (2340k kernel code, 14544k reserved, 116k data, 94k bss, 148k init) Calibrating delay loop... 33.38 BogoMIPS (lpj=166912) Mount-cache hash table entries: 512 device-tree: Duplicate name in /pci/mac-io, renamed to "ide#1" @@ -108,17 +108,15 @@ sda: [mac] sda1 sda2 sda3 sda4 sda5 sda6 sda7 sda8 sda9 sd 0:0:0:0: [sda] Attached SCSI disk pata_pdc2027x 0000:00:0e.0: version 0.9 -pata_pdc2027x 0000:00:0e.0: PLL input clock 16000 kHz +pata_pdc2027x 0000:00:0e.0: PLL input clock 1691742 kHz +pata_pdc2027x: Invalid PLL input clock 1691742kHz, give up! scsi1 : pata_pdc2027x scsi2 : pata_pdc2027x -ata1: PATA max UDMA/133 cmd 0xf10197c0 ctl 0xf1019fda bmdma 0xf1019000 irq 0 -ata2: PATA max UDMA/133 cmd 0xf10195c0 ctl 0xf1019dda bmdma 0xf1019008 irq 0 -ata1.00: ata_hpa_resize 1: sectors = 60036480, hpa_sectors = 60036480 +ata1: PATA max UDMA/133 cmd 0xf10197c0 ctl 0xf1019fda bmdma 0xf1019000 irq 24 +ata2: PATA max UDMA/133 cmd 0xf10195c0 ctl 0xf1019dda bmdma 0xf1019008 irq 24 ata1.00: ATA-5: IBM-DTLA-307030, TX4OA6AA, max UDMA/100 ata1.00: 60036480 sectors, multi 0: LBA -ata1.00: ata_hpa_resize 1: sectors = 60036480, hpa_sectors = 60036480 ata1.00: configured for UDMA/100 -ATA: abnormal status 0x8 on port 0xf10195df scsi 1:0:0:0: Direct-Access ATA IBM-DTLA-307030 TX4O PQ: 0 ANSI: 5 sd 1:0:0:0: [sdb] 60036480 512-byte hardware sectors (30739 MB) sd 1:0:0:0: [sdb] Write Protect is off @@ -128,7 +126,36 @@ sd 1:0:0:0: [sdb] Write Protect is off sd 1:0:0:0: [sdb] Mode Sense: 00 3a 00 00 sd 1:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA - sdb: sdb1 sdb2 sdb3 sdb4 < sdb5 sdb6 sdb7 > + sdb:<3>ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 +ata1.00: (BMDMA stat 0x4) +ata1.00: cmd c8/00:08:00:00:00/00:00:00:00:00/e0 tag 0 cdb 0x0 data 4096 in + res 51/84:00:07:00:00/00:00:00:00:00/e0 Emask 0x10 (ATA bus error) +ata1: soft resetting port +ata1.00: configured for UDMA/100 +ata1: EH complete +ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 +ata1.00: (BMDMA stat 0x4) +ata1.00: cmd c8/00:08:00:00:00/00:00:00:00:00/e0 tag 0 cdb 0x0 data 4096 in + res 51/84:00:07:00:00/00:00:00:00:00/e0 Emask 0x10 (ATA bus error) +ata1: soft resetting port +ata1.00: configured for UDMA/100 +ata1: EH complete +ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 +ata1.00: (BMDMA stat 0x4) +ata1.00: cmd c8/00:08:00:00:00/00:00:00:00:00/e0 tag 0 cdb 0x0 data 4096 in + res 51/84:00:07:00:00/00:00:00:00:00/e0 Emask 0x10 (ATA bus error) +ata1: soft resetting port +ata1.00: configured for UDMA/100 +ata1: EH complete +ata1.00: limiting speed to UDMA/66:PIO4 +ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 +ata1.00: (BMDMA stat 0x4) +ata1.00: cmd c8/00:08:00:00:00/00:00:00:00:00/e0 tag 0 cdb 0x0 data 4096 in + res 51/84:00:07:00:00/00:00:00:00:00/e0 Emask 0x10 (ATA bus error) +ata1: soft resetting port +ata1.00: configured for UDMA/66 +ata1: EH complete + sdb1 sdb2 sdb3 sdb4 < sdb5 sdb6 sdb7 > sd 1:0:0:0: [sdb] Attached SCSI disk mice: PS/2 mouse device common for all mice TCP cubic registered In fairness, this is a slightly non-standard PowerMac G3, in that it has a G4 upgrade processor. The firmware doesn't recognise the CPU and gives some CPU core frequency-related properties too low values. However, the bus frequency property _is_ correct, which is what most or all timing stuff should be based on. Looks like a platform bug. /Mikael - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
