epia-cn patch

[aaron lwe]

> Do you have the dsdt.dsl source? Where did it come from?

dsdt.c comes from disassembling the dsl file. the dsl file is
extracted from memory when booted with factory bios. I'll add that
file if necessary.
> Index: src/mainboard/via/epia-cn/fadt.c
>
> --- src/mainboard/via/epia-cn/fadt.c  (revision 0)
> +++ src/mainboard/via/epia-cn/fadt.c  (revision 0)
> @@ -0,0 +1,154 @@
> +/*
> ACPI - create the Fixed ACPI Description Tables (FADT)
> Copyright (C) 2004 Nick Barker
> Did you change anything in this file? Then I think you should add your copyright, possibly even remove Nick's.

yes, I changed the values.
> +void acpi_create_fadt(acpi_fadt_t *fadt,acpi_facs_t *facs,void *dsdt){
> acpi_header_t *header=&(fadt->header);
> memset((void *)fadt,0,sizeof(acpi_fadt_t));
> memcpy(header->signature,"FACP",4);
> header->length = 244;
> header->revision = 1;
> memcpy(header->oem_id,"CN700 ",6);
> memcpy(header->oem_table_id,"AWRDACPI",8);
> memcpy(header->asl_compiler_id,"AWRD",4);
> We are not Award. What is this about?

These values are extracted from factory bios FACP table, so I just keep them.
> header->asl_compiler_revision=0;
> fadt->firmware_ctrl=facs;
> fadt->dsdt= dsdt;
> fadt->preferred_pm_profile=0;
> fadt->sci_int=9;
> fadt->smi_cmd = 0x0;
> fadt->acpi_enable = 0x0;
> fadt->acpi_disable = 0x0;
> fadt->s4bios_req = 0x0;
> fadt->pstate_cnt = 0x0;
> fadt->pm1a_evt_blk = 0x400;
> fadt->pm1b_evt_blk = 0x0;
> fadt->pm1a_cnt_blk = 0x404;
> fadt->pm1b_cnt_blk = 0x0;
> fadt->pm2_cnt_blk = 0x0;
> fadt->pm_tmr_blk = 0x408;
> fadt->gpe0_blk = 0x420;
> fadt->gpe1_blk = 0x0;
> Where do all these magic values come from?

By extracting FACP table of the factory BIOS, these values are all in
that table.
> -/**
> Configure the bus between the cpu and the northbridge. This might be able to
> be moved to post-ram code in the future. For the most part, these registers
> should not be messed around with. These are too complex to explain short of
> copying the datasheets into the comments, but most of these values are from
> the BIOS Porting Guide, so they should work on any board. If they don't,
> try the values from your factory BIOS.
> TODO: Changing the DRAM frequency doesn't work (hard lockup)
> @param dev The northbridge's CPU Host Interface (D0F2)
> */
>
> static void c7_cpu_setup(device_t dev)
>  {
> Hey, please don't remove doxygen. :)

Oh...my bad ;-)
> Index: src/northbridge/via/cn700/northbridge.c
>
> --- src/northbridge/via/cn700/northbridge.c   (revision 3300)
> +++ src/northbridge/via/cn700/northbridge.c   (working copy)
> @@ -1,6 +1,8 @@
>  /*
> This file is part of the coreboot project.
> Copyright (C) 2008 VIA Technologies, Inc.
> Copyright (C) 2008 Aaron Lwe
> How is VIA involved in this?

I'm a VIA employee, so I think I should add VIA here, sorry not making
this clear.
> Thanks a lot for the patch! I guess Corey and Bari will have a go at

it but I'll try to test as well.
Thanks. If dram didn't work right, try to change the values of D0F2
registers in c7_cpu_setup to be the same as the facotry BIOS set.

-Aaron