/*
 * 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) {
                pci_unmap_biosrom(oprom);
                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;
}