cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

extdev.c (3140B)

      1/*
      2 * Copyright 2012 Nouveau Community
      3 *
      4 * Permission is hereby granted, free of charge, to any person obtaining a
      5 * copy of this software and associated documentation files (the "Software"),
      6 * to deal in the Software without restriction, including without limitation
      7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
      8 * and/or sell copies of the Software, and to permit persons to whom the
      9 * Software is furnished to do so, subject to the following conditions:
     10 *
     11 * The above copyright notice and this permission notice shall be included in
     12 * all copies or substantial portions of the Software.
     13 *
     14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
     17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
     18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
     19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
     20 * OTHER DEALINGS IN THE SOFTWARE.
     21 *
     22 * Authors: Martin Peres
     23 */
     24#include <subdev/bios.h>
     25#include <subdev/bios/dcb.h>
     26#include <subdev/bios/extdev.h>
     27
     28static u16
     29extdev_table(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *len, u8 *cnt)
     30{
     31	u8  dcb_ver, dcb_hdr, dcb_cnt, dcb_len;
     32	u16 dcb, extdev = 0;
     33
     34	dcb = dcb_table(bios, &dcb_ver, &dcb_hdr, &dcb_cnt, &dcb_len);
     35	if (!dcb || (dcb_ver != 0x30 && dcb_ver != 0x40 && dcb_ver != 0x41))
     36		return 0x0000;
     37
     38	extdev = nvbios_rd16(bios, dcb + 18);
     39	if (!extdev)
     40		return 0x0000;
     41
     42	*ver = nvbios_rd08(bios, extdev + 0);
     43	*hdr = nvbios_rd08(bios, extdev + 1);
     44	*cnt = nvbios_rd08(bios, extdev + 2);
     45	*len = nvbios_rd08(bios, extdev + 3);
     46	return extdev + *hdr;
     47}
     48
     49bool
     50nvbios_extdev_skip_probe(struct nvkm_bios *bios)
     51{
     52	u8  ver, hdr, len, cnt;
     53	u16 data = extdev_table(bios, &ver, &hdr, &len, &cnt);
     54	if (data && ver == 0x40 && hdr >= 5) {
     55		u8 flags = nvbios_rd08(bios, data - hdr + 4);
     56		if (flags & 1)
     57			return true;
     58	}
     59	return false;
     60}
     61
     62static u16
     63nvbios_extdev_entry(struct nvkm_bios *bios, int idx, u8 *ver, u8 *len)
     64{
     65	u8 hdr, cnt;
     66	u16 extdev = extdev_table(bios, ver, &hdr, len, &cnt);
     67	if (extdev && idx < cnt)
     68		return extdev + idx * *len;
     69	return 0x0000;
     70}
     71
     72static void
     73extdev_parse_entry(struct nvkm_bios *bios, u16 offset,
     74		   struct nvbios_extdev_func *entry)
     75{
     76	entry->type = nvbios_rd08(bios, offset + 0);
     77	entry->addr = nvbios_rd08(bios, offset + 1);
     78	entry->bus = (nvbios_rd08(bios, offset + 2) >> 4) & 1;
     79}
     80
     81int
     82nvbios_extdev_parse(struct nvkm_bios *bios, int idx,
     83		    struct nvbios_extdev_func *func)
     84{
     85	u8 ver, len;
     86	u16 entry;
     87
     88	if (!(entry = nvbios_extdev_entry(bios, idx, &ver, &len)))
     89		return -EINVAL;
     90
     91	extdev_parse_entry(bios, entry, func);
     92	return 0;
     93}
     94
     95int
     96nvbios_extdev_find(struct nvkm_bios *bios, enum nvbios_extdev_type type,
     97		   struct nvbios_extdev_func *func)
     98{
     99	u8 ver, len, i;
    100	u16 entry;
    101
    102	i = 0;
    103	while ((entry = nvbios_extdev_entry(bios, i++, &ver, &len))) {
    104		extdev_parse_entry(bios, entry, func);
    105		if (func->type == type)
    106			return 0;
    107	}
    108
    109	return -EINVAL;
    110}