text: /*
   * Probing flash chips with QINFO records.
   * (C) 2008 Korolev Alexey <akorolev@infradead.org>
   * (C) 2008 Vasiliy Leonenko <vasiliy.leonenko@gmail.com>
   *
   * 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; either version 2
   * of the License, or (at your option) any later version.
   *
   * 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 Street, Fifth Floor, Boston, MA
   * 02110-1301, USA.
   */
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/init.h>
  #include <linux/errno.h>
  #include <linux/slab.h>
  #include <linux/interrupt.h>
  
  #include <linux/mtd/xip.h>
  #include <linux/mtd/map.h>
  #include <linux/mtd/pfow.h>
  #include <linux/mtd/qinfo.h>
  
  static int lpddr_chip_setup(struct map_info *map, struct lpddr_private *lpddr);
  struct mtd_info *lpddr_probe(struct map_info *map);
  static struct lpddr_private *lpddr_probe_chip(struct map_info *map);
  static int lpddr_pfow_present(struct map_info *map,
  			struct lpddr_private *lpddr);
  
  static struct qinfo_query_info qinfo_array[] = {
  	/* General device info */
  	{0, 0, "DevSizeShift", "Device size 2^n bytes"},
  	{0, 3, "BufSizeShift", "Program buffer size 2^n bytes"},
  	/* Erase block information */
  	{1, 1, "TotalBlocksNum", "Total number of blocks"},
  	{1, 2, "UniformBlockSizeShift", "Uniform block size 2^n bytes"},
  	/* Partition information */
  	{2, 1, "HWPartsNum", "Number of hardware partitions"},
  	/* Optional features */
  	{5, 1, "SuspEraseSupp", "Suspend erase supported"},
  	/* Operation typical time */
  	{10, 0, "SingleWordProgTime", "Single word program 2^n u-sec"},
  	{10, 1, "ProgBufferTime", "Program buffer write 2^n u-sec"},
  	{10, 2, "BlockEraseTime", "Block erase 2^n m-sec"},
  	{10, 3, "FullChipEraseTime", "Full chip erase 2^n m-sec"},
  };
  
  static long lpddr_get_qinforec_pos(struct map_info *map, char *id_str)
  {
  	int qinfo_lines = sizeof(qinfo_array)/sizeof(struct qinfo_query_info);
  	int i;
  	int bankwidth = map_bankwidth(map) * 8;
  	int major, minor;
  
  	for (i = 0; i < qinfo_lines; i++) {
  		if (strcmp(id_str, qinfo_array[i].id_str) == 0) {
  			major = qinfo_array[i].major & ((1 << bankwidth) - 1);
  			minor = qinfo_array[i].minor & ((1 << bankwidth) - 1);
  			return minor | (major << bankwidth);
  		}
  	}
  	printk(KERN_ERR"%s qinfo id string is wrong! \n", map->name);
  	BUG();
  	return -1;
  }
  
  static uint16_t lpddr_info_query(struct map_info *map, char *id_str)
  {
  	unsigned int dsr, val;
  	int bits_per_chip = map_bankwidth(map) * 8;
  	unsigned long adr = lpddr_get_qinforec_pos(map, id_str);
  	int attempts = 20;
  
  	/* Write a request for the PFOW record */
  	map_write(map, CMD(LPDDR_INFO_QUERY),
  			map->pfow_base + PFOW_COMMAND_CODE);
  	map_write(map, CMD(adr & ((1 << bits_per_chip) - 1)),
  			map->pfow_base + PFOW_COMMAND_ADDRESS_L);
  	map_write(map, CMD(adr >> bits_per_chip),
  			map->pfow_base + PFOW_COMMAND_ADDRESS_H);
  	map_write(map, CMD(LPDDR_START_EXECUTION),
  			map->pfow_base + PFOW_COMMAND_EXECUTE);
  
  	while ((attempts--) > 0) {
  		dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
  		if (dsr & DSR_READY_STATUS)
  			break;
  		udelay(10);
  	}
  
  	val = CMDVAL(map_read(map, map->pfow_base + PFOW_COMMAND_DATA));
  	return val;
  }
  
  static int lpddr_pfow_present(struct map_info *map, struct lpddr_private *lpddr)
  {
  	map_word pfow_val[4];
  
  	/* Check identification string */
  	pfow_val[0] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_P);
  	pfow_val[1] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_F);
  	pfow_val[2] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_O);
  	pfow_val[3] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_W);
  
  	if (!map_word_equal(map, CMD('P'), pfow_val[0]))
  		goto out;
  
  	if (!map_word_equal(map, CMD('F'), pfow_val[1]))
  		goto out;
  
  	if (!map_word_equal(map, CMD('O'), pfow_val[2]))
  		goto out;
  
  	if (!map_word_equal(map, CMD('W'), pfow_val[3]))
  		goto out;
  
  	return 1;	/* "PFOW" is found */
  out:
  	printk(KERN_WARNING"%s: PFOW string at 0x%lx is not found \n",
  					map->name, map->pfow_base);
  	return 0;
  }
  
  static int lpddr_chip_setup(struct map_info *map, struct lpddr_private *lpddr)
  {
  
  	lpddr->qinfo = kzalloc(sizeof(struct qinfo_chip), GFP_KERNEL);
  	if (!lpddr->qinfo) {
  		printk(KERN_WARNING "%s: no memory for LPDDR qinfo structure\n",
  				map->name);
  		return 0;
  	}
  
  	/* Get the ManuID */
  	lpddr->ManufactId = CMDVAL(map_read(map, map->pfow_base + PFOW_MANUFACTURER_ID));
  	/* Get the DeviceID */
  	lpddr->DevId = CMDVAL(map_read(map, map->pfow_base + PFOW_DEVICE_ID));
  	/* read parameters from chip qinfo table */
  	lpddr->qinfo->DevSizeShift = lpddr_info_query(map, "DevSizeShift");
  	lpddr->qinfo->TotalBlocksNum = lpddr_info_query(map, "TotalBlocksNum");
  	lpddr->qinfo->BufSizeShift = lpddr_info_query(map, "BufSizeShift");
  	lpddr->qinfo->HWPartsNum = lpddr_info_query(map, "HWPartsNum");
  	lpddr->qinfo->UniformBlockSizeShift =
  				lpddr_info_query(map, "UniformBlockSizeShift");
  	lpddr->qinfo->SuspEraseSupp = lpddr_info_query(map, "SuspEraseSupp");
  	lpddr->qinfo->SingleWordProgTime =
  				lpddr_info_query(map, "SingleWordProgTime");
  	lpddr->qinfo->ProgBufferTime = lpddr_info_query(map, "ProgBufferTime");
  	lpddr->qinfo->BlockEraseTime = lpddr_info_query(map, "BlockEraseTime");
  	return 1;
  }
  static struct lpddr_private *lpddr_probe_chip(struct map_info *map)
  {
  	struct lpddr_private lpddr;
  	struct lpddr_private *retlpddr;
  	int numvirtchips;
  
  	if ((map->pfow_base + 0x1000) >= map->size) {
  		printk(KERN_NOTICE"%s Probe at base (0x%08lx) past the end of"
  				"the map(0x%08lx)\n", map->name,
  				(unsigned long)map->pfow_base, map->size - 1);
  		return NULL;
  	}
  	memset(&lpddr, 0, sizeof(struct lpddr_private));
  	if (!lpddr_pfow_present(map, &lpddr))
  		return NULL;
  
  	if (!lpddr_chip_setup(map, &lpddr))
  		return NULL;
  
  	/* Ok so we found a chip */
  	lpddr.chipshift = lpddr.qinfo->DevSizeShift;
  	lpddr.numchips = 1;
  
  	numvirtchips = lpddr.numchips * lpddr.qinfo->HWPartsNum;
  	retlpddr = kzalloc(sizeof(struct lpddr_private) +
  			numvirtchips * sizeof(struct flchip), GFP_KERNEL);
  	if (!retlpddr)
  		return NULL;
  
  	memcpy(retlpddr, &lpddr, sizeof(struct lpddr_private));
  
  	retlpddr->numchips = numvirtchips;
  	retlpddr->chipshift = retlpddr->qinfo->DevSizeShift -
  				__ffs(retlpddr->qinfo->HWPartsNum);
  
  	return retlpddr;
  }
  
  struct mtd_info *lpddr_probe(struct map_info *map)
  {
  	struct mtd_info *mtd = NULL;
  	struct lpddr_private *lpddr;
  
  	/* First probe the map to see if we havecan open PFOW here */
  	lpddr = lpddr_probe_chip(map);
  	if (!lpddr)
  		return NULL;
  
  	map->fldrv_priv = lpddr;
  	mtd = lpddr_cmdset(map);
  	if (mtd) {
  		if (mtd->size > map->size) {
  			printk(KERN_WARNING "Reducing visibility of %ldKiB chip"
  				"to %ldKiB\n", (unsigned long)mtd->size >> 10,
  				(unsigned long)map->size >> 10);
  			mtd->size = map->size;
  		}
  		return mtd;
  	}
  
  	kfree(lpddr->qinfo);
  	kfree(lpddr);
  	map->fldrv_priv = NULL;
  	return NULL;
  }
  
  static struct mtd_chip_driver lpddr_chipdrv = {
  	.probe		= lpddr_probe,
  	.name		= "qinfo_probe",
  	.module		= THIS_MODULE
  };
  
  static int __init lpddr_probe_init(void)
  {
  	register_mtd_chip_driver(&lpddr_chipdrv);
  	return 0;
  }
  
  static void __exit lpddr_probe_exit(void)
  {
  	unregister_mtd_chip_driver(&lpddr_chipdrv);
  }
  
  module_init(lpddr_probe_init);
  module_exit(lpddr_probe_exit);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Vasiliy Leonenko <vasiliy.leonenko@gmail.com>");
  MODULE_DESCRIPTION("Driver to probe qinfo flash chips");
  