[flashrom] [patch] add intel_piix4_gpo_set()
Carl-Daniel Hailfinger
c-d.hailfinger.devel.2006 at gmx.net
Tue Oct 6 16:27:52 CEST 2009
On 07.07.2009 15:10, Luc Verhaegen wrote:
> + /* dual function that need special enable. */
> + if ((gpo >= 22) && (gpo <= 26)) {
> + tmp = pci_read_long(dev, 0xB0); /* GENCFG */
> + switch (gpo) {
> + case 22: /* XBUS: XDIR#/GPO22 */
> + case 23: /* XBUS: XOE#/GPO23 */
> + tmp |= 1 << 28;
> + break;
> + case 24: /* RTCSS#/GPO24 */
> + tmp |= 1 << 29;
> + break;
> + case 25: /* RTCALE/GPO25 */
> + tmp |= 1 << 30;
> + break;
> + case 26: /* KBCSS#/GPO26 */
> + tmp |= 1 << 31;
> + break;
> + default:
>
If the default case triggers, you found a compiler bug. Remove.
> + fprintf(stderr, "\nERROR: Unsupported PIIX4 GPO%d.\n", gpo);
> + return -1;
> + }
> + pci_write_long(dev, 0xB0, tmp);
> + }
> +
> + /* GPO {0,8,27,28,30} are always available. */
> +
> + dev = pci_dev_find(0x8086, 0x7113); /* Intel PIIX4 PM */
> + if (!dev) {
> + fprintf(stderr, "\nERROR: Intel PIIX4 PM not found.\n");
> + return -1;
> + }
> +
> + /* PM IO base */
> + base = pci_read_long(dev, 0x40) & 0x0000FFC0;
> +
> + tmp = INL(base + 0x34); /* GPO register */
> + if (raise)
> + tmp |= 0x01 << gpo;
> + else
> + tmp |= ~(0x01 << gpo);
> + OUTL(tmp, base + 0x34);
> +
> + return 0;
> +}
> +
> +/**
> * Suited for VIAs EPIA M and MII, and maybe other CLE266 based EPIAs.
> *
> * We don't need to do this when using coreboot, GPIO15 is never lowered there.
> @@ -440,18 +512,7 @@
> */
> static int board_epox_ep_bx3(const char *name)
> {
> - uint8_t tmp;
> -
> - /* Raise GPIO22. */
> - tmp = INB(0x4036);
> - OUTB(tmp, 0xEB);
> -
> - tmp |= 0x40;
> -
> - OUTB(tmp, 0x4036);
> - OUTB(tmp, 0xEB);
> -
> - return 0;
> + return intel_piix4_gpo_set(22, 1);
> }
>
> /**
>
Ahem. This patch is not functionally equivalent. Not at all.
The old code:
- Read 8-bit value from port 0x4036. Write said value to port 0xeb. Set
bit 6 in value. Write value again to port 0xeb and write value to port
0x4036. No config space accesses.
The new code:
- Set bit 28 of 32-bit value in PCI config space of PIIX4 ISA at 0xb0.
Get PMBASE from PCI config space of PIIX4 PM. Read 32-bit value from
port PMBASE+0x34. Set bit 22 in value. Write value back to PMBASE+0x34.
Assuming PMBASE=0x4000, this is equivalent to setting bit 6 in the 8-bit
value at port 0x4036.
Difference:
- Port 0xeb is not written or read in the new code.
- PCI config space of PIIX4 ISA at 0xb0 was not read or written in the
old code.
I'd like to see an explanation for this.
Regards,
Carl-Daniel
--
http://www.hailfinger.org/
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