probe_roms.c

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/*
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 * The full GNU General Public License is included in this distribution
 * in the file called LICENSE.GPL.
 */

/* probe_roms - scan for oem parameters */

#include <linux/kernel.h>
#include <linux/firmware.h>
#include <linux/uaccess.h>
#include <linux/efi.h>
#include <asm/probe_roms.h>

#include "isci.h"
#include "task.h"
#include "probe_roms.h"

static efi_char16_t isci_efivar_name[] = {
    'R', 's', 't', 'S', 'c', 'u', 'O'
};

struct isci_orom *isci_request_oprom(struct pci_dev *pdev)
{
    void __iomem *oprom = pci_map_biosrom(pdev);
    struct isci_orom *rom = NULL;
    size_t len, i;
    int j;
    char oem_sig[4];
    struct isci_oem_hdr oem_hdr;
    u8 *tmp, sum;

    if (!oprom)
        return NULL;

    len = pci_biosrom_size(pdev);
    rom = devm_kzalloc(&pdev->dev, sizeof(*rom), GFP_KERNEL);
    if (!rom) {
        dev_warn(&pdev->dev,
             "Unable to allocate memory for orom\n");
        return NULL;
    }

    for (i = 0; i < len && rom; i += ISCI_OEM_SIG_SIZE) {
        memcpy_fromio(oem_sig, oprom + i, ISCI_OEM_SIG_SIZE);

        /* we think we found the OEM table */
        if (memcmp(oem_sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) == 0) {
            size_t copy_len;

            memcpy_fromio(&oem_hdr, oprom + i, sizeof(oem_hdr));

            copy_len = min(oem_hdr.len - sizeof(oem_hdr),
                       sizeof(*rom));

            memcpy_fromio(rom,
                      oprom + i + sizeof(oem_hdr),
                      copy_len);

            /* calculate checksum */
            tmp = (u8 *)&oem_hdr;
            for (j = 0, sum = 0; j < sizeof(oem_hdr); j++, tmp++)
                sum += *tmp;

            tmp = (u8 *)rom;
            for (j = 0; j < sizeof(*rom); j++, tmp++)
                sum += *tmp;

            if (sum != 0) {
                dev_warn(&pdev->dev,
                     "OEM table checksum failed\n");
                continue;
            }

            /* keep going if that's not the oem param table */
            if (memcmp(rom->hdr.signature,
                   ISCI_ROM_SIG,
                   ISCI_ROM_SIG_SIZE) != 0)
                continue;

            dev_info(&pdev->dev,
                 "OEM parameter table found in OROM\n");
            break;
        }
    }

    if (i >= len) {
        dev_err(&pdev->dev, "oprom parse error\n");
        rom = NULL;
    }
    pci_unmap_biosrom(oprom);

    return rom;
}

struct isci_orom *isci_request_firmware(struct pci_dev *pdev, const struct firmware *fw)
{
    struct isci_orom *orom = NULL, *data;
    int i, j;

    if (request_firmware(&fw, ISCI_FW_NAME, &pdev->dev) != 0)
        return NULL;

    if (fw->size < sizeof(*orom))
        goto out;

    data = (struct isci_orom *)fw->data;

    if (strncmp(ISCI_ROM_SIG, data->hdr.signature,
            strlen(ISCI_ROM_SIG)) != 0)
        goto out;

    orom = devm_kzalloc(&pdev->dev, fw->size, GFP_KERNEL);
    if (!orom)
        goto out;

    memcpy(orom, fw->data, fw->size);

    if (is_c0(pdev) || is_c1(pdev))
        goto out;

    /*
     * deprecated: override default amp_control for pre-preproduction
     * silicon revisions
     */
    for (i = 0; i < ARRAY_SIZE(orom->ctrl); i++)
        for (j = 0; j < ARRAY_SIZE(orom->ctrl[i].phys); j++) {
            orom->ctrl[i].phys[j].afe_tx_amp_control0 = 0xe7c03;
            orom->ctrl[i].phys[j].afe_tx_amp_control1 = 0xe7c03;
            orom->ctrl[i].phys[j].afe_tx_amp_control2 = 0xe7c03;
            orom->ctrl[i].phys[j].afe_tx_amp_control3 = 0xe7c03;
        }
 out:
    release_firmware(fw);

    return orom;
}

static struct efi *get_efi(void)
{
#ifdef CONFIG_EFI
    return &efi;
#else
    return NULL;
#endif
}

struct isci_orom *isci_get_efi_var(struct pci_dev *pdev)
{
    efi_status_t status;
    struct isci_orom *rom;
    struct isci_oem_hdr *oem_hdr;
    u8 *tmp, sum;
    int j;
    unsigned long data_len;
    u8 *efi_data;
    u32 efi_attrib = 0;

    data_len = 1024;
    efi_data = devm_kzalloc(&pdev->dev, data_len, GFP_KERNEL);
    if (!efi_data) {
        dev_warn(&pdev->dev,
             "Unable to allocate memory for EFI data\n");
        return NULL;
    }

    rom = (struct isci_orom *)(efi_data + sizeof(struct isci_oem_hdr));

    if (get_efi())
        status = get_efi()->get_variable(isci_efivar_name,
                         &ISCI_EFI_VENDOR_GUID,
                         &efi_attrib,
                         &data_len,
                         efi_data);
    else
        status = EFI_NOT_FOUND;

    if (status != EFI_SUCCESS) {
        dev_warn(&pdev->dev,
             "Unable to obtain EFI var data for OEM parms\n");
        return NULL;
    }

    oem_hdr = (struct isci_oem_hdr *)efi_data;

    if (memcmp(oem_hdr->sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) != 0) {
        dev_warn(&pdev->dev,
             "Invalid OEM header signature\n");
        return NULL;
    }

    /* calculate checksum */
    tmp = (u8 *)efi_data;
    for (j = 0, sum = 0; j < (sizeof(*oem_hdr) + sizeof(*rom)); j++, tmp++)
        sum += *tmp;

    if (sum != 0) {
        dev_warn(&pdev->dev,
             "OEM table checksum failed\n");
        return NULL;
    }

    if (memcmp(rom->hdr.signature,
           ISCI_ROM_SIG,
           ISCI_ROM_SIG_SIZE) != 0) {
        dev_warn(&pdev->dev,
             "Invalid OEM table signature\n");
        return NULL;
    }

    return rom;
}