[PATCH 2/2] NAND: nandsim sector-wise allocation
Vijay Kumar
vijaykumar at bravegnu.org
Thu Oct 5 13:13:11 EDT 2006
For page wise allocation, an array of flash page pointers is allocated
during initialization. The flash pages are themselves allocated when a
write occurs to the page. The flash pages are deallocated when they
are erased.
The init, read, prog and erase operations are moved to separate functions,
and for each allocation/mapping type a set of init/read/prog/erase
functions are defined.
Signed-off-by: Vijay Kumar <vijaykumar at bravegnu.org>
Index: linux-2.6-mtd-quilt/drivers/mtd/nand/Kconfig
===================================================================
--- linux-2.6-mtd-quilt.orig/drivers/mtd/nand/Kconfig 2006-10-01 20:35:47.000000000 +0530
+++ linux-2.6-mtd-quilt/drivers/mtd/nand/Kconfig 2006-10-02 18:20:42.000000000 +0530
@@ -250,10 +250,21 @@
The flash data is stored in an image mapped to memory.
config MTD_NAND_NANDSIM_CHIP_ALLOC
- bool "Use allocated memory"
+ bool "Allocate entire chip"
help
- The flash data is stored in allocated memory.
+ The flash data is stored in allocated memory. The entire
+ memory to hold the flash data is allocated during
+ initialization.
+config MTD_NAND_NANDSIM_PAGE_ALLOC
+ bool "Allocate flash pages as required"
+ help
+ The flash data is stored in allocated memory. The
+ allocation is done on a per page basis, when data is
+ written to the page. Enables simulation of
+ higher capacity NAND devices in systems that do
+ not have as much RAM.
+
endchoice
config MTD_NAND_NANDSIM_ABS_POS
Index: linux-2.6-mtd-quilt/drivers/mtd/nand/nandsim.c
===================================================================
--- linux-2.6-mtd-quilt.orig/drivers/mtd/nand/nandsim.c 2006-10-01 20:39:39.000000000 +0530
+++ linux-2.6-mtd-quilt/drivers/mtd/nand/nandsim.c 2006-10-02 21:40:54.000000000 +0530
@@ -37,7 +37,7 @@
#include <linux/mtd/nand.h>
#include <linux/mtd/partitions.h>
#include <linux/delay.h>
-#ifdef CONFIG_MTD_NAND_NANDSIM_CHIP_MAP
+#if defined(CONFIG_MTD_NAND_NANDSIM_CHIP_MAP)
#include <asm/io.h>
#endif
@@ -45,8 +45,10 @@
#define CONFIG_NANDSIM_CHIP_MAP 1
#elif defined(CONFIG_MTD_NAND_NANDSIM_CHIP_ALLOC)
#define CONFIG_NANDSIM_CHIP_ALLOC 1
+#elif defined(CONFIG_MTD_NAND_NANDSIM_PAGE_ALLOC)
+#define CONFIG_NANDSIM_PAGE_ALLOC 1
#else
-#error "One of chip map or chip alloc has to be selected."
+#error "One of chip map, chip alloc or page alloc has to be selected."
#endif
/* Default simulator parameters values */
@@ -239,6 +241,11 @@
*/
#define NS_MAX_PREVSTATES 1
+union ns_mem_t {
+ u_char *byte;
+ uint16_t *word;
+};
+
/*
* The structure which describes all the internal simulator data.
*/
@@ -257,16 +264,15 @@
uint16_t stateidx; /* current state index */
/* The simulated NAND flash image */
- union flash_media {
- u_char *byte;
- uint16_t *word;
- } mem;
+
+#if defined(CONFIG_NANDSIM_CHIP_MAP) || defined(CONFIG_NANDSIM_CHIP_ALLOC)
+ union ns_mem_t mem;
+#elif defined(CONFIG_NANDSIM_PAGE_ALLOC)
+ union ns_mem_t *pages;
+#endif
/* Internal buffer of page + OOB size bytes */
- union internal_buffer {
- u_char *byte; /* for byte access */
- uint16_t *word; /* for 16-bit word access */
- } buf;
+ union ns_mem_t buf;
/* NAND flash "geometry" */
struct nandsin_geometry {
@@ -354,6 +360,85 @@
static u_char ns_verify_buf[NS_LARGEST_PAGE_SIZE];
+#if defined(CONFIG_NANDSIM_CHIP_MAP)
+
+static int
+alloc_map_device(struct nandsim *ns)
+{
+ /* Map / allocate and initialize the flash image */
+ ns->mem.byte = ioremap(CONFIG_NANDSIM_ABS_POS, ns->geom.totszoob);
+ if (!ns->mem.byte) {
+ NS_ERR("alloc_map: failed to map the NAND flash image at address %p\n",
+ (void *)CONFIG_NANDSIM_ABS_POS);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void
+free_unmap_device(struct nandsim *ns)
+{
+ iounmap(ns->mem.byte);
+}
+
+#elif defined(CONFIG_NANDSIM_CHIP_ALLOC)
+
+static int
+alloc_map_device(struct nandsim *ns)
+{
+ ns->mem.byte = vmalloc(ns->geom.totszoob);
+ if (!ns->mem.byte) {
+ NS_ERR("alloc_map: unable to allocate %u bytes for flash image\n",
+ ns->geom.totszoob);
+ return -ENOMEM;
+ }
+ memset(ns->mem.byte, 0xFF, ns->geom.totszoob);
+
+ return 0;
+}
+
+static void
+free_unmap_device(struct nandsim *ns)
+{
+ vfree(ns->mem.byte);
+}
+
+#elif defined(CONFIG_NANDSIM_PAGE_ALLOC)
+
+static int
+alloc_map_device(struct nandsim *ns)
+{
+ int i;
+
+ ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem_t));
+ if (!ns->pages) {
+ NS_ERR("alloc_map: unable to allocate page array\n");
+ return -ENOMEM;
+ }
+ for (i = 0; i < ns->geom.pgnum; i++) {
+ ns->pages[i].byte = NULL;
+ }
+
+ return 0;
+}
+
+static void
+free_unmap_device(struct nandsim *ns)
+{
+ int i;
+
+ if (ns->pages) {
+ for (i = 0; i < ns->geom.pgnum; i++) {
+ if (ns->pages[i].byte)
+ kfree(ns->pages[i].byte);
+ }
+ vfree(ns->pages);
+ }
+}
+
+#endif
+
/*
* Initialize the nandsim structure.
*
@@ -448,23 +533,8 @@
printk("sector address bytes: %u\n", ns->geom.secaddrbytes);
printk("options: %#x\n", ns->options);
- /* Map / allocate and initialize the flash image */
-#ifdef CONFIG_NANDSIM_CHIP_MAP
- ns->mem.byte = ioremap(CONFIG_NANDSIM_ABS_POS, ns->geom.totszoob);
- if (!ns->mem.byte) {
- NS_ERR("init_nandsim: failed to map the NAND flash image at address %p\n",
- (void *)CONFIG_NS_ABS_POS);
- return -ENOMEM;
- }
-#else
- ns->mem.byte = vmalloc(ns->geom.totszoob);
- if (!ns->mem.byte) {
- NS_ERR("init_nandsim: unable to allocate %u bytes for flash image\n",
- ns->geom.totszoob);
- return -ENOMEM;
- }
- memset(ns->mem.byte, 0xFF, ns->geom.totszoob);
-#endif
+ if (alloc_map_device(ns) != 0)
+ goto error;
/* Allocate / initialize the internal buffer */
ns->buf.byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
@@ -483,11 +553,7 @@
return 0;
error:
-#ifdef CONFIG_NANDSIM_CHIP_MAP
- iounmap(ns->mem.byte);
-#else
- vfree(ns->mem.byte);
-#endif
+ free_unmap_device(ns);
return -ENOMEM;
}
@@ -500,11 +566,7 @@
{
kfree(ns->buf.byte);
-#ifdef CONFIG_NANDSIM_CHIP_MAP
- iounmap(ns->mem.byte);
-#else
- vfree(ns->mem.byte);
-#endif
+ free_unmap_device(ns);
return;
}
@@ -799,6 +861,116 @@
return -1;
}
+#if defined(CONFIG_NANDSIM_CHIP_MAP) || defined(CONFIG_NANDSIM_CHIP_ALLOC)
+
+/*
+ * Copy NUM bytes from the specified page/offset to the buffer.
+ */
+static void read_page(struct nandsim *ns, int num)
+{
+ memcpy(ns->buf.byte, ns->mem.byte + NS_RAW_OFFSET(ns)
+ + ns->regs.off, num);
+}
+
+/*
+ * Erase the selected sector.
+ */
+static void erase_sector(struct nandsim *ns)
+{
+ memset(ns->mem.byte + NS_RAW_OFFSET(ns), 0xFF, ns->geom.secszoob);
+}
+
+
+/*
+ * Program NUM bytes into the specified page/offset in the flash from
+ * the buffer.
+ *
+ * Returns 0 on success, -1 on failure.
+ */
+static int prog_page(struct nandsim *ns, int num)
+{
+ int i;
+
+ for (i = 0; i < num; i++) {
+ ns->mem.byte[NS_RAW_OFFSET(ns) + ns->regs.off + i] &= ns->buf.byte[i];
+ }
+
+ return 0;
+}
+
+#elif defined(CONFIG_NANDSIM_PAGE_ALLOC)
+
+/*
+ * Returns a pointer to the current page.
+ */
+static inline union ns_mem_t *NS_GET_PAGE(struct nandsim *ns)
+{
+ return &(ns->pages[ns->regs.row]);
+}
+
+/*
+ * Retuns a pointer to the current byte, within the current page.
+ */
+static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns)
+{
+ return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off;
+}
+
+static void read_page(struct nandsim *ns, int num)
+{
+ union ns_mem_t *mypage;
+
+ mypage = NS_GET_PAGE(ns);
+ if (mypage->byte == NULL) {
+ NS_DBG("read_page: page %d not allocated\n", ns->regs.row);
+ memset(ns->buf.byte, 0xFF, num);
+ } else {
+ NS_DBG("read_page: page %d allocated, reading from %d\n",
+ ns->regs.row, ns->regs.column + ns->regs.off);
+ memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num);
+ }
+}
+
+static void erase_sector(struct nandsim *ns)
+{
+ union ns_mem_t *mypage;
+ int i;
+
+ mypage = NS_GET_PAGE(ns);
+ for (i = 0; i < ns->geom.pgsec; i++) {
+ if (mypage->byte != NULL) {
+ NS_DBG("erase_sector: freeing page %d\n", ns->regs.row+i);
+ kfree(mypage->byte);
+ mypage->byte = NULL;
+ }
+ mypage++;
+ }
+}
+
+static int prog_page(struct nandsim *ns, int num)
+{
+ union ns_mem_t *mypage;
+ u_char *pg_off;
+
+ mypage = NS_GET_PAGE(ns);
+ if (mypage->byte == NULL) {
+ NS_DBG("prog_page: allocating page %d\n", ns->regs.row);
+ mypage->byte = kmalloc(ns->geom.pgszoob, GFP_KERNEL);
+ if (mypage->byte == NULL) {
+ NS_ERR("prog_page: error allocating memory for page %d\n", ns->regs.row);
+ return -1;
+ }
+ memset(mypage->byte, 0xFF, ns->geom.pgszoob);
+ }
+
+ pg_off = NS_PAGE_BYTE_OFF(ns);
+ memcpy(pg_off, ns->buf.byte, num);
+
+ return 0;
+}
+
+#endif
+
/*
* If state has any action bit, perform this action.
*
@@ -807,7 +979,7 @@
static int
do_state_action(struct nandsim *ns, uint32_t action)
{
- int i, num;
+ int num;
int busdiv = ns->busw == 8 ? 1 : 2;
action &= ACTION_MASK;
@@ -831,7 +1003,7 @@
break;
}
num = ns->geom.pgszoob - ns->regs.off - ns->regs.column;
- memcpy(ns->buf.byte, ns->mem.byte + NS_RAW_OFFSET(ns) + ns->regs.off, num);
+ read_page(ns, num);
NS_DBG("do_state_action: (ACTION_CPY:) copy %d bytes to int buf, raw offset %d\n",
num, NS_RAW_OFFSET(ns) + ns->regs.off);
@@ -872,7 +1044,7 @@
ns->regs.row, NS_RAW_OFFSET(ns));
NS_LOG("erase sector %d\n", ns->regs.row >> (ns->geom.secshift - ns->geom.pgshift));
- memset(ns->mem.byte + NS_RAW_OFFSET(ns), 0xFF, ns->geom.secszoob);
+ erase_sector(ns);
NS_MDELAY(erase_delay);
@@ -895,8 +1067,9 @@
return -1;
}
- for (i = 0; i < num; i++)
- ns->mem.byte[NS_RAW_OFFSET(ns) + ns->regs.off + i] &= ns->buf.byte[i];
+ if (prog_page(ns, num) == -1) {
+ return -1;
+ }
NS_DBG("do_state_action: copy %d bytes from int buf to (%#x, %#x), raw off = %d\n",
num, ns->regs.row, ns->regs.column, NS_RAW_OFFSET(ns) + ns->regs.off);
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