/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2011 Google Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * 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.
 */

#include <console/console.h>
#include <console/usb.h>
#include <bootmode.h>
#include <cf9_reset.h>
#include <string.h>
#include <arch/io.h>
#include <device/pci_ops.h>
#include <cbmem.h>
#include <arch/cbfs.h>
#include <cbfs.h>
#include <ip_checksum.h>
#include <pc80/mc146818rtc.h>
#include <device/pci_def.h>
#include <lib.h>
#include <mrc_cache.h>
#include <timestamp.h>
#include "raminit.h"
#include "pei_data.h"
#include "sandybridge.h"
#include <security/vboot/vboot_common.h>
#include <southbridge/intel/bd82x6x/pch.h>

/* Management Engine is in the southbridge */
#include <southbridge/intel/bd82x6x/me.h>

/*
 * MRC scrambler seed offsets should be reserved in
 * mainboard cmos.layout and not covered by checksum.
 */
#if CONFIG(USE_OPTION_TABLE)
#include "option_table.h"
#define CMOS_OFFSET_MRC_SEED     (CMOS_VSTART_mrc_scrambler_seed >> 3)
#define CMOS_OFFSET_MRC_SEED_S3  (CMOS_VSTART_mrc_scrambler_seed_s3 >> 3)
#define CMOS_OFFSET_MRC_SEED_CHK (CMOS_VSTART_mrc_scrambler_seed_chk >> 3)
#else
#define CMOS_OFFSET_MRC_SEED     152
#define CMOS_OFFSET_MRC_SEED_S3  156
#define CMOS_OFFSET_MRC_SEED_CHK 160
#endif

#define MRC_CACHE_VERSION 0

void save_mrc_data(struct pei_data *pei_data)
{
	u16 c1, c2, checksum;

	/* Save the MRC S3 restore data to cbmem */
	mrc_cache_stash_data(MRC_TRAINING_DATA, MRC_CACHE_VERSION,
			pei_data->mrc_output,
			pei_data->mrc_output_len);

	/* Save the MRC seed values to CMOS */
	cmos_write32(CMOS_OFFSET_MRC_SEED, pei_data->scrambler_seed);
	printk(BIOS_DEBUG, "Save scrambler seed    0x%08x to CMOS 0x%02x\n",
	       pei_data->scrambler_seed, CMOS_OFFSET_MRC_SEED);

	cmos_write32(CMOS_OFFSET_MRC_SEED_S3, pei_data->scrambler_seed_s3);
	printk(BIOS_DEBUG, "Save s3 scrambler seed 0x%08x to CMOS 0x%02x\n",
	       pei_data->scrambler_seed_s3, CMOS_OFFSET_MRC_SEED_S3);

	/* Save a simple checksum of the seed values */
	c1 = compute_ip_checksum((u8*)&pei_data->scrambler_seed,
				 sizeof(u32));
	c2 = compute_ip_checksum((u8*)&pei_data->scrambler_seed_s3,
				 sizeof(u32));
	checksum = add_ip_checksums(sizeof(u32), c1, c2);

	cmos_write(checksum & 0xff, CMOS_OFFSET_MRC_SEED_CHK);
	cmos_write((checksum >> 8) & 0xff, CMOS_OFFSET_MRC_SEED_CHK+1);
}

static void prepare_mrc_cache(struct pei_data *pei_data)
{
	struct region_device rdev;
	u16 c1, c2, checksum, seed_checksum;

	// preset just in case there is an error
	pei_data->mrc_input = NULL;
	pei_data->mrc_input_len = 0;

	/* Read scrambler seeds from CMOS */
	pei_data->scrambler_seed = cmos_read32(CMOS_OFFSET_MRC_SEED);
	printk(BIOS_DEBUG, "Read scrambler seed    0x%08x from CMOS 0x%02x\n",
	       pei_data->scrambler_seed, CMOS_OFFSET_MRC_SEED);

	pei_data->scrambler_seed_s3 = cmos_read32(CMOS_OFFSET_MRC_SEED_S3);
	printk(BIOS_DEBUG, "Read S3 scrambler seed 0x%08x from CMOS 0x%02x\n",
	       pei_data->scrambler_seed_s3, CMOS_OFFSET_MRC_SEED_S3);

	/* Compute seed checksum and compare */
	c1 = compute_ip_checksum((u8*)&pei_data->scrambler_seed,
				 sizeof(u32));
	c2 = compute_ip_checksum((u8*)&pei_data->scrambler_seed_s3,
				 sizeof(u32));
	checksum = add_ip_checksums(sizeof(u32), c1, c2);

	seed_checksum = cmos_read(CMOS_OFFSET_MRC_SEED_CHK);
	seed_checksum |= cmos_read(CMOS_OFFSET_MRC_SEED_CHK+1) << 8;

	if (checksum != seed_checksum) {
		printk(BIOS_ERR, "%s: invalid seed checksum\n", __func__);
		pei_data->scrambler_seed = 0;
		pei_data->scrambler_seed_s3 = 0;
		return;
	}

	if (mrc_cache_get_current(MRC_TRAINING_DATA, MRC_CACHE_VERSION,
					&rdev)) {
		/* error message printed in find_current_mrc_cache */
		return;
	}

	pei_data->mrc_input = rdev_mmap_full(&rdev);
	pei_data->mrc_input_len = region_device_sz(&rdev);

	printk(BIOS_DEBUG, "%s: at %p, size %x\n",
	       __func__, pei_data->mrc_input, pei_data->mrc_input_len);
}

static const char *ecc_decoder[] = {
	"inactive",
	"active on IO",
	"disabled on IO",
	"active"
};

/*
 * Dump in the log memory controller configuration as read from the memory
 * controller registers.
 */
static void report_memory_config(void)
{
	u32 addr_decoder_common, addr_decode_ch[2];
	int i;

	addr_decoder_common = MCHBAR32(0x5000);
	addr_decode_ch[0] = MCHBAR32(0x5004);
	addr_decode_ch[1] = MCHBAR32(0x5008);

	printk(BIOS_DEBUG, "memcfg DDR3 clock %d MHz\n",
	       (MCHBAR32(0x5e04) * 13333 * 2 + 50)/100);
	printk(BIOS_DEBUG, "memcfg channel assignment: A: %d, B % d, C % d\n",
	       addr_decoder_common & 3,
	       (addr_decoder_common >> 2) & 3,
	       (addr_decoder_common >> 4) & 3);

	for (i = 0; i < ARRAY_SIZE(addr_decode_ch); i++) {
		u32 ch_conf = addr_decode_ch[i];
		printk(BIOS_DEBUG, "memcfg channel[%d] config (%8.8x):\n",
		       i, ch_conf);
		printk(BIOS_DEBUG, "   ECC %s\n",
		       ecc_decoder[(ch_conf >> 24) & 3]);
		printk(BIOS_DEBUG, "   enhanced interleave mode %s\n",
		       ((ch_conf >> 22) & 1) ? "on" : "off");
		printk(BIOS_DEBUG, "   rank interleave %s\n",
		       ((ch_conf >> 21) & 1) ? "on" : "off");
		printk(BIOS_DEBUG, "   DIMMA %d MB width x%d %s rank%s\n",
		       ((ch_conf >> 0) & 0xff) * 256,
		       ((ch_conf >> 19) & 1) ? 16 : 8,
		       ((ch_conf >> 17) & 1) ? "dual" : "single",
		       ((ch_conf >> 16) & 1) ? "" : ", selected");
		printk(BIOS_DEBUG, "   DIMMB %d MB width x%d %s rank%s\n",
		       ((ch_conf >> 8) & 0xff) * 256,
		       ((ch_conf >> 20) & 1) ? 16 : 8,
		       ((ch_conf >> 18) & 1) ? "dual" : "single",
		       ((ch_conf >> 16) & 1) ? ", selected" : "");
	}
}

/**
 * Find PEI executable in coreboot filesystem and execute it.
 *
 * @param pei_data: configuration data for UEFI PEI reference code
 */
void sdram_initialize(struct pei_data *pei_data)
{
	struct sys_info sysinfo;
	int (*entry) (struct pei_data *pei_data) __attribute__((regparm(1)));

	/* Wait for ME to be ready */
	intel_early_me_init();
	intel_early_me_uma_size();

	printk(BIOS_DEBUG, "Starting UEFI PEI System Agent\n");

	memset(&sysinfo, 0, sizeof(sysinfo));

	sysinfo.boot_path = pei_data->boot_mode;

	/*
	 * Do not pass MRC data in for recovery mode boot,
	 * Always pass it in for S3 resume.
	 */
	if (!vboot_recovery_mode_enabled() || pei_data->boot_mode == 2)
		prepare_mrc_cache(pei_data);

	/* If MRC data is not found we cannot continue S3 resume. */
	if (pei_data->boot_mode == 2 && !pei_data->mrc_input) {
		printk(BIOS_DEBUG, "Giving up in sdram_initialize: No MRC data\n");
		system_reset();
	}

	/* Pass console handler in pei_data */
	pei_data->tx_byte = do_putchar;

	/* Locate and call UEFI System Agent binary. */
	entry = cbfs_boot_map_with_leak("mrc.bin", CBFS_TYPE_MRC, NULL);
	if (entry) {
		int rv;
		rv = entry (pei_data);
		if (rv) {
			switch (rv) {
			case -1:
				printk(BIOS_ERR, "PEI version mismatch.\n");
				break;
			case -2:
				printk(BIOS_ERR, "Invalid memory frequency.\n");
				break;
			default:
				printk(BIOS_ERR, "MRC returned %x.\n", rv);
			}
			die("Nonzero MRC return value.\n");
		}
	} else {
		die("UEFI PEI System Agent not found.\n");
	}

	/* mrc.bin reconfigures USB, so reinit it to have debug */
	if (CONFIG(USBDEBUG_IN_PRE_RAM))
		usbdebug_hw_init(true);

	/* For reference print the System Agent version
	 * after executing the UEFI PEI stage.
	 */
	u32 version = MCHBAR32(0x5034);
	printk(BIOS_DEBUG, "System Agent Version %d.%d.%d Build %d\n",
		version >> 24, (version >> 16) & 0xff,
		(version >> 8) & 0xff, version & 0xff);

	/* Send ME init done for SandyBridge here.  This is done
	 * inside the SystemAgent binary on IvyBridge. */
	if (BASE_REV_SNB ==
	    (pci_read_config16(PCI_CPU_DEVICE, PCI_DEVICE_ID) & BASE_REV_MASK))
		intel_early_me_init_done(ME_INIT_STATUS_SUCCESS);
	else
		intel_early_me_status();

	report_memory_config();
}

/* These are the location and structure of MRC_VAR data in CAR. */
#define DCACHE_RAM_MRC_VAR_BASE \
	(CONFIG_DCACHE_RAM_BASE + CONFIG_DCACHE_RAM_SIZE)

struct mrc_var_data {
	u32 acpi_timer_flag;
	u32 pool_used;
	u32 pool_base;
	u32 tx_byte;
	u32 reserved[4];
} __packed;

void perform_raminit(int s3resume)
{
	int cbmem_was_initted;
	struct pei_data pei_data;
	struct mrc_var_data *mrc_var;

	/* Prepare USB controller early in S3 resume */
	if (!mainboard_should_reset_usb(s3resume))
		enable_usb_bar();

	mainboard_fill_pei_data(&pei_data);

	post_code(0x3a);

	/* Fix spd_data. MRC only uses spd_data[0] and ignores the other */
	for (size_t i = 1; i < ARRAY_SIZE(pei_data.spd_data); i++) {
		if (pei_data.spd_data[i][0] && !pei_data.spd_data[0][0]) {
			memcpy(pei_data.spd_data[0], pei_data.spd_data[i],
			       sizeof(pei_data.spd_data[0]));
		} else if (pei_data.spd_data[i][0] && pei_data.spd_data[0][0]) {
			if (memcmp(pei_data.spd_data[i], pei_data.spd_data[0],
			    sizeof(pei_data.spd_data[0])) != 0)
				die("Onboard SPDs must match each other");
		}
	}

	pei_data.boot_mode = s3resume ? 2 : 0;
	timestamp_add_now(TS_BEFORE_INITRAM);
	sdram_initialize(&pei_data);

	mrc_var = (void *)DCACHE_RAM_MRC_VAR_BASE;
	/* Sanity check mrc_var location by verifying a known field. */
	if (mrc_var->tx_byte == (uintptr_t)pei_data.tx_byte) {
		printk(BIOS_DEBUG, "MRC_VAR pool occupied [%08x,%08x]\n",
		       mrc_var->pool_base,
		       mrc_var->pool_base + mrc_var->pool_used);
	} else {
		printk(BIOS_ERR, "Could not parse MRC_VAR data\n");
		hexdump32(BIOS_ERR, mrc_var, sizeof(*mrc_var)/sizeof(u32));
	}

	cbmem_was_initted = !cbmem_recovery(s3resume);
	if (!s3resume)
		save_mrc_data(&pei_data);

	if (s3resume && !cbmem_was_initted) {
		/* Failed S3 resume, reset to come up cleanly */
		system_reset();
	}
}