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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/mtd/nand/s3c2410.c
downloadblackbird-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
blackbird-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/mtd/nand/s3c2410.c')
-rw-r--r--drivers/mtd/nand/s3c2410.c704
1 files changed, 704 insertions, 0 deletions
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
new file mode 100644
index 000000000000..d05e9b97947d
--- /dev/null
+++ b/drivers/mtd/nand/s3c2410.c
@@ -0,0 +1,704 @@
+/* linux/drivers/mtd/nand/s3c2410.c
+ *
+ * Copyright (c) 2004 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * Samsung S3C2410 NAND driver
+ *
+ * Changelog:
+ * 21-Sep-2004 BJD Initial version
+ * 23-Sep-2004 BJD Mulitple device support
+ * 28-Sep-2004 BJD Fixed ECC placement for Hardware mode
+ * 12-Oct-2004 BJD Fixed errors in use of platform data
+ *
+ * $Id: s3c2410.c,v 1.7 2005/01/05 18:05:14 dwmw2 Exp $
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <config/mtd/nand/s3c2410/hwecc.h>
+#include <config/mtd/nand/s3c2410/debug.h>
+
+#ifdef CONFIG_MTD_NAND_S3C2410_DEBUG
+#define DEBUG
+#endif
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/partitions.h>
+
+#include <asm/io.h>
+#include <asm/mach-types.h>
+#include <asm/hardware/clock.h>
+
+#include <asm/arch/regs-nand.h>
+#include <asm/arch/nand.h>
+
+#define PFX "s3c2410-nand: "
+
+#ifdef CONFIG_MTD_NAND_S3C2410_HWECC
+static int hardware_ecc = 1;
+#else
+static int hardware_ecc = 0;
+#endif
+
+/* new oob placement block for use with hardware ecc generation
+ */
+
+static struct nand_oobinfo nand_hw_eccoob = {
+ .useecc = MTD_NANDECC_AUTOPLACE,
+ .eccbytes = 3,
+ .eccpos = {0, 1, 2 },
+ .oobfree = { {8, 8} }
+};
+
+/* controller and mtd information */
+
+struct s3c2410_nand_info;
+
+struct s3c2410_nand_mtd {
+ struct mtd_info mtd;
+ struct nand_chip chip;
+ struct s3c2410_nand_set *set;
+ struct s3c2410_nand_info *info;
+ int scan_res;
+};
+
+/* overview of the s3c2410 nand state */
+
+struct s3c2410_nand_info {
+ /* mtd info */
+ struct nand_hw_control controller;
+ struct s3c2410_nand_mtd *mtds;
+ struct s3c2410_platform_nand *platform;
+
+ /* device info */
+ struct device *device;
+ struct resource *area;
+ struct clk *clk;
+ void *regs;
+ int mtd_count;
+};
+
+/* conversion functions */
+
+static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
+{
+ return container_of(mtd, struct s3c2410_nand_mtd, mtd);
+}
+
+static struct s3c2410_nand_info *s3c2410_nand_mtd_toinfo(struct mtd_info *mtd)
+{
+ return s3c2410_nand_mtd_toours(mtd)->info;
+}
+
+static struct s3c2410_nand_info *to_nand_info(struct device *dev)
+{
+ return dev_get_drvdata(dev);
+}
+
+static struct s3c2410_platform_nand *to_nand_plat(struct device *dev)
+{
+ return dev->platform_data;
+}
+
+/* timing calculations */
+
+#define NS_IN_KHZ 10000000
+
+static int s3c2410_nand_calc_rate(int wanted, unsigned long clk, int max)
+{
+ int result;
+
+ result = (wanted * NS_IN_KHZ) / clk;
+ result++;
+
+ pr_debug("result %d from %ld, %d\n", result, clk, wanted);
+
+ if (result > max) {
+ printk("%d ns is too big for current clock rate %ld\n",
+ wanted, clk);
+ return -1;
+ }
+
+ if (result < 1)
+ result = 1;
+
+ return result;
+}
+
+#define to_ns(ticks,clk) (((clk) * (ticks)) / NS_IN_KHZ)
+
+/* controller setup */
+
+static int s3c2410_nand_inithw(struct s3c2410_nand_info *info,
+ struct device *dev)
+{
+ struct s3c2410_platform_nand *plat = to_nand_plat(dev);
+ unsigned int tacls, twrph0, twrph1;
+ unsigned long clkrate = clk_get_rate(info->clk);
+ unsigned long cfg;
+
+ /* calculate the timing information for the controller */
+
+ if (plat != NULL) {
+ tacls = s3c2410_nand_calc_rate(plat->tacls, clkrate, 8);
+ twrph0 = s3c2410_nand_calc_rate(plat->twrph0, clkrate, 8);
+ twrph1 = s3c2410_nand_calc_rate(plat->twrph1, clkrate, 8);
+ } else {
+ /* default timings */
+ tacls = 8;
+ twrph0 = 8;
+ twrph1 = 8;
+ }
+
+ if (tacls < 0 || twrph0 < 0 || twrph1 < 0) {
+ printk(KERN_ERR PFX "cannot get timings suitable for board\n");
+ return -EINVAL;
+ }
+
+ printk(KERN_INFO PFX "timing: Tacls %ldns, Twrph0 %ldns, Twrph1 %ldns\n",
+ to_ns(tacls, clkrate),
+ to_ns(twrph0, clkrate),
+ to_ns(twrph1, clkrate));
+
+ cfg = S3C2410_NFCONF_EN;
+ cfg |= S3C2410_NFCONF_TACLS(tacls-1);
+ cfg |= S3C2410_NFCONF_TWRPH0(twrph0-1);
+ cfg |= S3C2410_NFCONF_TWRPH1(twrph1-1);
+
+ pr_debug(PFX "NF_CONF is 0x%lx\n", cfg);
+
+ writel(cfg, info->regs + S3C2410_NFCONF);
+ return 0;
+}
+
+/* select chip */
+
+static void s3c2410_nand_select_chip(struct mtd_info *mtd, int chip)
+{
+ struct s3c2410_nand_info *info;
+ struct s3c2410_nand_mtd *nmtd;
+ struct nand_chip *this = mtd->priv;
+ unsigned long cur;
+
+ nmtd = this->priv;
+ info = nmtd->info;
+
+ cur = readl(info->regs + S3C2410_NFCONF);
+
+ if (chip == -1) {
+ cur |= S3C2410_NFCONF_nFCE;
+ } else {
+ if (chip > nmtd->set->nr_chips) {
+ printk(KERN_ERR PFX "chip %d out of range\n", chip);
+ return;
+ }
+
+ if (info->platform != NULL) {
+ if (info->platform->select_chip != NULL)
+ (info->platform->select_chip)(nmtd->set, chip);
+ }
+
+ cur &= ~S3C2410_NFCONF_nFCE;
+ }
+
+ writel(cur, info->regs + S3C2410_NFCONF);
+}
+
+/* command and control functions */
+
+static void s3c2410_nand_hwcontrol(struct mtd_info *mtd, int cmd)
+{
+ struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
+ unsigned long cur;
+
+ switch (cmd) {
+ case NAND_CTL_SETNCE:
+ cur = readl(info->regs + S3C2410_NFCONF);
+ cur &= ~S3C2410_NFCONF_nFCE;
+ writel(cur, info->regs + S3C2410_NFCONF);
+ break;
+
+ case NAND_CTL_CLRNCE:
+ cur = readl(info->regs + S3C2410_NFCONF);
+ cur |= S3C2410_NFCONF_nFCE;
+ writel(cur, info->regs + S3C2410_NFCONF);
+ break;
+
+ /* we don't need to implement these */
+ case NAND_CTL_SETCLE:
+ case NAND_CTL_CLRCLE:
+ case NAND_CTL_SETALE:
+ case NAND_CTL_CLRALE:
+ pr_debug(PFX "s3c2410_nand_hwcontrol(%d) unusedn", cmd);
+ break;
+ }
+}
+
+/* s3c2410_nand_command
+ *
+ * This function implements sending commands and the relevant address
+ * information to the chip, via the hardware controller. Since the
+ * S3C2410 generates the correct ALE/CLE signaling automatically, we
+ * do not need to use hwcontrol.
+*/
+
+static void s3c2410_nand_command (struct mtd_info *mtd, unsigned command,
+ int column, int page_addr)
+{
+ register struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
+ register struct nand_chip *this = mtd->priv;
+
+ /*
+ * Write out the command to the device.
+ */
+ if (command == NAND_CMD_SEQIN) {
+ int readcmd;
+
+ if (column >= mtd->oobblock) {
+ /* OOB area */
+ column -= mtd->oobblock;
+ readcmd = NAND_CMD_READOOB;
+ } else if (column < 256) {
+ /* First 256 bytes --> READ0 */
+ readcmd = NAND_CMD_READ0;
+ } else {
+ column -= 256;
+ readcmd = NAND_CMD_READ1;
+ }
+
+ writeb(readcmd, info->regs + S3C2410_NFCMD);
+ }
+ writeb(command, info->regs + S3C2410_NFCMD);
+
+ /* Set ALE and clear CLE to start address cycle */
+
+ if (column != -1 || page_addr != -1) {
+
+ /* Serially input address */
+ if (column != -1) {
+ /* Adjust columns for 16 bit buswidth */
+ if (this->options & NAND_BUSWIDTH_16)
+ column >>= 1;
+ writeb(column, info->regs + S3C2410_NFADDR);
+ }
+ if (page_addr != -1) {
+ writeb((unsigned char) (page_addr), info->regs + S3C2410_NFADDR);
+ writeb((unsigned char) (page_addr >> 8), info->regs + S3C2410_NFADDR);
+ /* One more address cycle for higher density devices */
+ if (this->chipsize & 0x0c000000)
+ writeb((unsigned char) ((page_addr >> 16) & 0x0f),
+ info->regs + S3C2410_NFADDR);
+ }
+ /* Latch in address */
+ }
+
+ /*
+ * program and erase have their own busy handlers
+ * status and sequential in needs no delay
+ */
+ switch (command) {
+
+ case NAND_CMD_PAGEPROG:
+ case NAND_CMD_ERASE1:
+ case NAND_CMD_ERASE2:
+ case NAND_CMD_SEQIN:
+ case NAND_CMD_STATUS:
+ return;
+
+ case NAND_CMD_RESET:
+ if (this->dev_ready)
+ break;
+
+ udelay(this->chip_delay);
+ writeb(NAND_CMD_STATUS, info->regs + S3C2410_NFCMD);
+
+ while ( !(this->read_byte(mtd) & 0x40));
+ return;
+
+ /* This applies to read commands */
+ default:
+ /*
+ * If we don't have access to the busy pin, we apply the given
+ * command delay
+ */
+ if (!this->dev_ready) {
+ udelay (this->chip_delay);
+ return;
+ }
+ }
+
+ /* Apply this short delay always to ensure that we do wait tWB in
+ * any case on any machine. */
+ ndelay (100);
+ /* wait until command is processed */
+ while (!this->dev_ready(mtd));
+}
+
+
+/* s3c2410_nand_devready()
+ *
+ * returns 0 if the nand is busy, 1 if it is ready
+*/
+
+static int s3c2410_nand_devready(struct mtd_info *mtd)
+{
+ struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
+
+ return readb(info->regs + S3C2410_NFSTAT) & S3C2410_NFSTAT_BUSY;
+}
+
+/* ECC handling functions */
+
+static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
+ u_char *read_ecc, u_char *calc_ecc)
+{
+ pr_debug("s3c2410_nand_correct_data(%p,%p,%p,%p)\n",
+ mtd, dat, read_ecc, calc_ecc);
+
+ pr_debug("eccs: read %02x,%02x,%02x vs calc %02x,%02x,%02x\n",
+ read_ecc[0], read_ecc[1], read_ecc[2],
+ calc_ecc[0], calc_ecc[1], calc_ecc[2]);
+
+ if (read_ecc[0] == calc_ecc[0] &&
+ read_ecc[1] == calc_ecc[1] &&
+ read_ecc[2] == calc_ecc[2])
+ return 0;
+
+ /* we curently have no method for correcting the error */
+
+ return -1;
+}
+
+static void s3c2410_nand_enable_hwecc(struct mtd_info *mtd, int mode)
+{
+ struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
+ unsigned long ctrl;
+
+ ctrl = readl(info->regs + S3C2410_NFCONF);
+ ctrl |= S3C2410_NFCONF_INITECC;
+ writel(ctrl, info->regs + S3C2410_NFCONF);
+}
+
+static int s3c2410_nand_calculate_ecc(struct mtd_info *mtd,
+ const u_char *dat, u_char *ecc_code)
+{
+ struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
+
+ ecc_code[0] = readb(info->regs + S3C2410_NFECC + 0);
+ ecc_code[1] = readb(info->regs + S3C2410_NFECC + 1);
+ ecc_code[2] = readb(info->regs + S3C2410_NFECC + 2);
+
+ pr_debug("calculate_ecc: returning ecc %02x,%02x,%02x\n",
+ ecc_code[0], ecc_code[1], ecc_code[2]);
+
+ return 0;
+}
+
+
+/* over-ride the standard functions for a little more speed? */
+
+static void s3c2410_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+ struct nand_chip *this = mtd->priv;
+ readsb(this->IO_ADDR_R, buf, len);
+}
+
+static void s3c2410_nand_write_buf(struct mtd_info *mtd,
+ const u_char *buf, int len)
+{
+ struct nand_chip *this = mtd->priv;
+ writesb(this->IO_ADDR_W, buf, len);
+}
+
+/* device management functions */
+
+static int s3c2410_nand_remove(struct device *dev)
+{
+ struct s3c2410_nand_info *info = to_nand_info(dev);
+
+ dev_set_drvdata(dev, NULL);
+
+ if (info == NULL)
+ return 0;
+
+ /* first thing we need to do is release all our mtds
+ * and their partitions, then go through freeing the
+ * resources used
+ */
+
+ if (info->mtds != NULL) {
+ struct s3c2410_nand_mtd *ptr = info->mtds;
+ int mtdno;
+
+ for (mtdno = 0; mtdno < info->mtd_count; mtdno++, ptr++) {
+ pr_debug("releasing mtd %d (%p)\n", mtdno, ptr);
+ nand_release(&ptr->mtd);
+ }
+
+ kfree(info->mtds);
+ }
+
+ /* free the common resources */
+
+ if (info->clk != NULL && !IS_ERR(info->clk)) {
+ clk_disable(info->clk);
+ clk_unuse(info->clk);
+ clk_put(info->clk);
+ }
+
+ if (info->regs != NULL) {
+ iounmap(info->regs);
+ info->regs = NULL;
+ }
+
+ if (info->area != NULL) {
+ release_resource(info->area);
+ kfree(info->area);
+ info->area = NULL;
+ }
+
+ kfree(info);
+
+ return 0;
+}
+
+#ifdef CONFIG_MTD_PARTITIONS
+static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
+ struct s3c2410_nand_mtd *mtd,
+ struct s3c2410_nand_set *set)
+{
+ if (set == NULL)
+ return add_mtd_device(&mtd->mtd);
+
+ if (set->nr_partitions > 0 && set->partitions != NULL) {
+ return add_mtd_partitions(&mtd->mtd,
+ set->partitions,
+ set->nr_partitions);
+ }
+
+ return add_mtd_device(&mtd->mtd);
+}
+#else
+static int s3c2410_nand_add_partition(struct s3c2410_nand_info *info,
+ struct s3c2410_nand_mtd *mtd,
+ struct s3c2410_nand_set *set)
+{
+ return add_mtd_device(&mtd->mtd);
+}
+#endif
+
+/* s3c2410_nand_init_chip
+ *
+ * init a single instance of an chip
+*/
+
+static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info,
+ struct s3c2410_nand_mtd *nmtd,
+ struct s3c2410_nand_set *set)
+{
+ struct nand_chip *chip = &nmtd->chip;
+
+ chip->IO_ADDR_R = (char *)info->regs + S3C2410_NFDATA;
+ chip->IO_ADDR_W = (char *)info->regs + S3C2410_NFDATA;
+ chip->hwcontrol = s3c2410_nand_hwcontrol;
+ chip->dev_ready = s3c2410_nand_devready;
+ chip->cmdfunc = s3c2410_nand_command;
+ chip->write_buf = s3c2410_nand_write_buf;
+ chip->read_buf = s3c2410_nand_read_buf;
+ chip->select_chip = s3c2410_nand_select_chip;
+ chip->chip_delay = 50;
+ chip->priv = nmtd;
+ chip->options = 0;
+ chip->controller = &info->controller;
+
+ nmtd->info = info;
+ nmtd->mtd.priv = chip;
+ nmtd->set = set;
+
+ if (hardware_ecc) {
+ chip->correct_data = s3c2410_nand_correct_data;
+ chip->enable_hwecc = s3c2410_nand_enable_hwecc;
+ chip->calculate_ecc = s3c2410_nand_calculate_ecc;
+ chip->eccmode = NAND_ECC_HW3_512;
+ chip->autooob = &nand_hw_eccoob;
+ } else {
+ chip->eccmode = NAND_ECC_SOFT;
+ }
+}
+
+/* s3c2410_nand_probe
+ *
+ * called by device layer when it finds a device matching
+ * one our driver can handled. This code checks to see if
+ * it can allocate all necessary resources then calls the
+ * nand layer to look for devices
+*/
+
+static int s3c2410_nand_probe(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct s3c2410_platform_nand *plat = to_nand_plat(dev);
+ struct s3c2410_nand_info *info;
+ struct s3c2410_nand_mtd *nmtd;
+ struct s3c2410_nand_set *sets;
+ struct resource *res;
+ int err = 0;
+ int size;
+ int nr_sets;
+ int setno;
+
+ pr_debug("s3c2410_nand_probe(%p)\n", dev);
+
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (info == NULL) {
+ printk(KERN_ERR PFX "no memory for flash info\n");
+ err = -ENOMEM;
+ goto exit_error;
+ }
+
+ memzero(info, sizeof(*info));
+ dev_set_drvdata(dev, info);
+
+ spin_lock_init(&info->controller.lock);
+
+ /* get the clock source and enable it */
+
+ info->clk = clk_get(dev, "nand");
+ if (IS_ERR(info->clk)) {
+ printk(KERN_ERR PFX "failed to get clock");
+ err = -ENOENT;
+ goto exit_error;
+ }
+
+ clk_use(info->clk);
+ clk_enable(info->clk);
+
+ /* allocate and map the resource */
+
+ res = pdev->resource; /* assume that the flash has one resource */
+ size = res->end - res->start + 1;
+
+ info->area = request_mem_region(res->start, size, pdev->name);
+
+ if (info->area == NULL) {
+ printk(KERN_ERR PFX "cannot reserve register region\n");
+ err = -ENOENT;
+ goto exit_error;
+ }
+
+ info->device = dev;
+ info->platform = plat;
+ info->regs = ioremap(res->start, size);
+
+ if (info->regs == NULL) {
+ printk(KERN_ERR PFX "cannot reserve register region\n");
+ err = -EIO;
+ goto exit_error;
+ }
+
+ printk(KERN_INFO PFX "mapped registers at %p\n", info->regs);
+
+ /* initialise the hardware */
+
+ err = s3c2410_nand_inithw(info, dev);
+ if (err != 0)
+ goto exit_error;
+
+ sets = (plat != NULL) ? plat->sets : NULL;
+ nr_sets = (plat != NULL) ? plat->nr_sets : 1;
+
+ info->mtd_count = nr_sets;
+
+ /* allocate our information */
+
+ size = nr_sets * sizeof(*info->mtds);
+ info->mtds = kmalloc(size, GFP_KERNEL);
+ if (info->mtds == NULL) {
+ printk(KERN_ERR PFX "failed to allocate mtd storage\n");
+ err = -ENOMEM;
+ goto exit_error;
+ }
+
+ memzero(info->mtds, size);
+
+ /* initialise all possible chips */
+
+ nmtd = info->mtds;
+
+ for (setno = 0; setno < nr_sets; setno++, nmtd++) {
+ pr_debug("initialising set %d (%p, info %p)\n",
+ setno, nmtd, info);
+
+ s3c2410_nand_init_chip(info, nmtd, sets);
+
+ nmtd->scan_res = nand_scan(&nmtd->mtd,
+ (sets) ? sets->nr_chips : 1);
+
+ if (nmtd->scan_res == 0) {
+ s3c2410_nand_add_partition(info, nmtd, sets);
+ }
+
+ if (sets != NULL)
+ sets++;
+ }
+
+ pr_debug("initialised ok\n");
+ return 0;
+
+ exit_error:
+ s3c2410_nand_remove(dev);
+
+ if (err == 0)
+ err = -EINVAL;
+ return err;
+}
+
+static struct device_driver s3c2410_nand_driver = {
+ .name = "s3c2410-nand",
+ .bus = &platform_bus_type,
+ .probe = s3c2410_nand_probe,
+ .remove = s3c2410_nand_remove,
+};
+
+static int __init s3c2410_nand_init(void)
+{
+ printk("S3C2410 NAND Driver, (c) 2004 Simtec Electronics\n");
+ return driver_register(&s3c2410_nand_driver);
+}
+
+static void __exit s3c2410_nand_exit(void)
+{
+ driver_unregister(&s3c2410_nand_driver);
+}
+
+module_init(s3c2410_nand_init);
+module_exit(s3c2410_nand_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
+MODULE_DESCRIPTION("S3C2410 MTD NAND driver");
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