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

probe_roms.c (5456B)


      1/*
      2 * This file is provided under a dual BSD/GPLv2 license.  When using or
      3 * redistributing this file, you may do so under either license.
      4 *
      5 * GPL LICENSE SUMMARY
      6 *
      7 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
      8 *
      9 * This program is free software; you can redistribute it and/or modify
     10 * it under the terms of version 2 of the GNU General Public License as
     11 * published by the Free Software Foundation.
     12 *
     13 * This program is distributed in the hope that it will be useful, but
     14 * WITHOUT ANY WARRANTY; without even the implied warranty of
     15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     16 * General Public License for more details.
     17 *
     18 * You should have received a copy of the GNU General Public License
     19 * along with this program; if not, write to the Free Software
     20 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
     21 * The full GNU General Public License is included in this distribution
     22 * in the file called LICENSE.GPL.
     23 */
     24
     25/* probe_roms - scan for oem parameters */
     26
     27#include <linux/kernel.h>
     28#include <linux/firmware.h>
     29#include <linux/uaccess.h>
     30#include <linux/efi.h>
     31#include <asm/probe_roms.h>
     32
     33#include "isci.h"
     34#include "task.h"
     35#include "probe_roms.h"
     36
     37static efi_char16_t isci_efivar_name[] = {
     38	'R', 's', 't', 'S', 'c', 'u', 'O'
     39};
     40
     41struct isci_orom *isci_request_oprom(struct pci_dev *pdev)
     42{
     43	void __iomem *oprom = pci_map_biosrom(pdev);
     44	struct isci_orom *rom = NULL;
     45	size_t len, i;
     46	int j;
     47	char oem_sig[4];
     48	struct isci_oem_hdr oem_hdr;
     49	u8 *tmp, sum;
     50
     51	if (!oprom)
     52		return NULL;
     53
     54	len = pci_biosrom_size(pdev);
     55	rom = devm_kzalloc(&pdev->dev, sizeof(*rom), GFP_KERNEL);
     56	if (!rom) {
     57		pci_unmap_biosrom(oprom);
     58		dev_warn(&pdev->dev,
     59			 "Unable to allocate memory for orom\n");
     60		return NULL;
     61	}
     62
     63	for (i = 0; i < len && rom; i += ISCI_OEM_SIG_SIZE) {
     64		memcpy_fromio(oem_sig, oprom + i, ISCI_OEM_SIG_SIZE);
     65
     66		/* we think we found the OEM table */
     67		if (memcmp(oem_sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) == 0) {
     68			size_t copy_len;
     69
     70			memcpy_fromio(&oem_hdr, oprom + i, sizeof(oem_hdr));
     71
     72			copy_len = min(oem_hdr.len - sizeof(oem_hdr),
     73				       sizeof(*rom));
     74
     75			memcpy_fromio(rom,
     76				      oprom + i + sizeof(oem_hdr),
     77				      copy_len);
     78
     79			/* calculate checksum */
     80			tmp = (u8 *)&oem_hdr;
     81			for (j = 0, sum = 0; j < sizeof(oem_hdr); j++, tmp++)
     82				sum += *tmp;
     83
     84			tmp = (u8 *)rom;
     85			for (j = 0; j < sizeof(*rom); j++, tmp++)
     86				sum += *tmp;
     87
     88			if (sum != 0) {
     89				dev_warn(&pdev->dev,
     90					 "OEM table checksum failed\n");
     91				continue;
     92			}
     93
     94			/* keep going if that's not the oem param table */
     95			if (memcmp(rom->hdr.signature,
     96				   ISCI_ROM_SIG,
     97				   ISCI_ROM_SIG_SIZE) != 0)
     98				continue;
     99
    100			dev_info(&pdev->dev,
    101				 "OEM parameter table found in OROM\n");
    102			break;
    103		}
    104	}
    105
    106	if (i >= len) {
    107		dev_err(&pdev->dev, "oprom parse error\n");
    108		rom = NULL;
    109	}
    110	pci_unmap_biosrom(oprom);
    111
    112	return rom;
    113}
    114
    115struct isci_orom *isci_request_firmware(struct pci_dev *pdev, const struct firmware *fw)
    116{
    117	struct isci_orom *orom = NULL, *data;
    118	int i, j;
    119
    120	if (request_firmware(&fw, ISCI_FW_NAME, &pdev->dev) != 0)
    121		return NULL;
    122
    123	if (fw->size < sizeof(*orom))
    124		goto out;
    125
    126	data = (struct isci_orom *)fw->data;
    127
    128	if (strncmp(ISCI_ROM_SIG, data->hdr.signature,
    129		    strlen(ISCI_ROM_SIG)) != 0)
    130		goto out;
    131
    132	orom = devm_kzalloc(&pdev->dev, fw->size, GFP_KERNEL);
    133	if (!orom)
    134		goto out;
    135
    136	memcpy(orom, fw->data, fw->size);
    137
    138	if (is_c0(pdev) || is_c1(pdev))
    139		goto out;
    140
    141	/*
    142	 * deprecated: override default amp_control for pre-preproduction
    143	 * silicon revisions
    144	 */
    145	for (i = 0; i < ARRAY_SIZE(orom->ctrl); i++)
    146		for (j = 0; j < ARRAY_SIZE(orom->ctrl[i].phys); j++) {
    147			orom->ctrl[i].phys[j].afe_tx_amp_control0 = 0xe7c03;
    148			orom->ctrl[i].phys[j].afe_tx_amp_control1 = 0xe7c03;
    149			orom->ctrl[i].phys[j].afe_tx_amp_control2 = 0xe7c03;
    150			orom->ctrl[i].phys[j].afe_tx_amp_control3 = 0xe7c03;
    151		}
    152 out:
    153	release_firmware(fw);
    154
    155	return orom;
    156}
    157
    158static struct efi *get_efi(void)
    159{
    160#ifdef CONFIG_EFI
    161	return &efi;
    162#else
    163	return NULL;
    164#endif
    165}
    166
    167struct isci_orom *isci_get_efi_var(struct pci_dev *pdev)
    168{
    169	efi_status_t status;
    170	struct isci_orom *rom;
    171	struct isci_oem_hdr *oem_hdr;
    172	u8 *tmp, sum;
    173	int j;
    174	unsigned long data_len;
    175	u8 *efi_data;
    176	u32 efi_attrib = 0;
    177
    178	data_len = 1024;
    179	efi_data = devm_kzalloc(&pdev->dev, data_len, GFP_KERNEL);
    180	if (!efi_data) {
    181		dev_warn(&pdev->dev,
    182			 "Unable to allocate memory for EFI data\n");
    183		return NULL;
    184	}
    185
    186	rom = (struct isci_orom *)(efi_data + sizeof(struct isci_oem_hdr));
    187
    188	if (get_efi())
    189		status = get_efi()->get_variable(isci_efivar_name,
    190						 &ISCI_EFI_VENDOR_GUID,
    191						 &efi_attrib,
    192						 &data_len,
    193						 efi_data);
    194	else
    195		status = EFI_NOT_FOUND;
    196
    197	if (status != EFI_SUCCESS) {
    198		dev_warn(&pdev->dev,
    199			 "Unable to obtain EFI var data for OEM parms\n");
    200		return NULL;
    201	}
    202
    203	oem_hdr = (struct isci_oem_hdr *)efi_data;
    204
    205	if (memcmp(oem_hdr->sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) != 0) {
    206		dev_warn(&pdev->dev,
    207			 "Invalid OEM header signature\n");
    208		return NULL;
    209	}
    210
    211	/* calculate checksum */
    212	tmp = (u8 *)efi_data;
    213	for (j = 0, sum = 0; j < (sizeof(*oem_hdr) + sizeof(*rom)); j++, tmp++)
    214		sum += *tmp;
    215
    216	if (sum != 0) {
    217		dev_warn(&pdev->dev,
    218			 "OEM table checksum failed\n");
    219		return NULL;
    220	}
    221
    222	if (memcmp(rom->hdr.signature,
    223		   ISCI_ROM_SIG,
    224		   ISCI_ROM_SIG_SIZE) != 0) {
    225		dev_warn(&pdev->dev,
    226			 "Invalid OEM table signature\n");
    227		return NULL;
    228	}
    229
    230	return rom;
    231}