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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
commite5fd91f1ef340da553f7a79da9540c3db711c937 (patch)
treeb11842027dc6641da63f4bcc524f8678263304a3 /drivers/mtd/chips/cfi_util.c
parent2a9b0348e685a63d97486f6749622b61e9e3292f (diff)
Linux-libre 4.2-gnu
Diffstat (limited to 'drivers/mtd/chips/cfi_util.c')
-rw-r--r--drivers/mtd/chips/cfi_util.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/mtd/chips/cfi_util.c b/drivers/mtd/chips/cfi_util.c
index 09c79bd0b..6f16552cd 100644
--- a/drivers/mtd/chips/cfi_util.c
+++ b/drivers/mtd/chips/cfi_util.c
@@ -23,6 +23,194 @@
#include <linux/mtd/map.h>
#include <linux/mtd/cfi.h>
+void cfi_udelay(int us)
+{
+ if (us >= 1000) {
+ msleep((us+999)/1000);
+ } else {
+ udelay(us);
+ cond_resched();
+ }
+}
+EXPORT_SYMBOL(cfi_udelay);
+
+/*
+ * Returns the command address according to the given geometry.
+ */
+uint32_t cfi_build_cmd_addr(uint32_t cmd_ofs,
+ struct map_info *map, struct cfi_private *cfi)
+{
+ unsigned bankwidth = map_bankwidth(map);
+ unsigned interleave = cfi_interleave(cfi);
+ unsigned type = cfi->device_type;
+ uint32_t addr;
+
+ addr = (cmd_ofs * type) * interleave;
+
+ /* Modify the unlock address if we are in compatibility mode.
+ * For 16bit devices on 8 bit busses
+ * and 32bit devices on 16 bit busses
+ * set the low bit of the alternating bit sequence of the address.
+ */
+ if (((type * interleave) > bankwidth) && ((cmd_ofs & 0xff) == 0xaa))
+ addr |= (type >> 1)*interleave;
+
+ return addr;
+}
+EXPORT_SYMBOL(cfi_build_cmd_addr);
+
+/*
+ * Transforms the CFI command for the given geometry (bus width & interleave).
+ * It looks too long to be inline, but in the common case it should almost all
+ * get optimised away.
+ */
+map_word cfi_build_cmd(u_long cmd, struct map_info *map, struct cfi_private *cfi)
+{
+ map_word val = { {0} };
+ int wordwidth, words_per_bus, chip_mode, chips_per_word;
+ unsigned long onecmd;
+ int i;
+
+ /* We do it this way to give the compiler a fighting chance
+ of optimising away all the crap for 'bankwidth' larger than
+ an unsigned long, in the common case where that support is
+ disabled */
+ if (map_bankwidth_is_large(map)) {
+ wordwidth = sizeof(unsigned long);
+ words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
+ } else {
+ wordwidth = map_bankwidth(map);
+ words_per_bus = 1;
+ }
+
+ chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
+ chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
+
+ /* First, determine what the bit-pattern should be for a single
+ device, according to chip mode and endianness... */
+ switch (chip_mode) {
+ default: BUG();
+ case 1:
+ onecmd = cmd;
+ break;
+ case 2:
+ onecmd = cpu_to_cfi16(map, cmd);
+ break;
+ case 4:
+ onecmd = cpu_to_cfi32(map, cmd);
+ break;
+ }
+
+ /* Now replicate it across the size of an unsigned long, or
+ just to the bus width as appropriate */
+ switch (chips_per_word) {
+ default: BUG();
+#if BITS_PER_LONG >= 64
+ case 8:
+ onecmd |= (onecmd << (chip_mode * 32));
+#endif
+ case 4:
+ onecmd |= (onecmd << (chip_mode * 16));
+ case 2:
+ onecmd |= (onecmd << (chip_mode * 8));
+ case 1:
+ ;
+ }
+
+ /* And finally, for the multi-word case, replicate it
+ in all words in the structure */
+ for (i=0; i < words_per_bus; i++) {
+ val.x[i] = onecmd;
+ }
+
+ return val;
+}
+EXPORT_SYMBOL(cfi_build_cmd);
+
+unsigned long cfi_merge_status(map_word val, struct map_info *map,
+ struct cfi_private *cfi)
+{
+ int wordwidth, words_per_bus, chip_mode, chips_per_word;
+ unsigned long onestat, res = 0;
+ int i;
+
+ /* We do it this way to give the compiler a fighting chance
+ of optimising away all the crap for 'bankwidth' larger than
+ an unsigned long, in the common case where that support is
+ disabled */
+ if (map_bankwidth_is_large(map)) {
+ wordwidth = sizeof(unsigned long);
+ words_per_bus = (map_bankwidth(map)) / wordwidth; // i.e. normally 1
+ } else {
+ wordwidth = map_bankwidth(map);
+ words_per_bus = 1;
+ }
+
+ chip_mode = map_bankwidth(map) / cfi_interleave(cfi);
+ chips_per_word = wordwidth * cfi_interleave(cfi) / map_bankwidth(map);
+
+ onestat = val.x[0];
+ /* Or all status words together */
+ for (i=1; i < words_per_bus; i++) {
+ onestat |= val.x[i];
+ }
+
+ res = onestat;
+ switch(chips_per_word) {
+ default: BUG();
+#if BITS_PER_LONG >= 64
+ case 8:
+ res |= (onestat >> (chip_mode * 32));
+#endif
+ case 4:
+ res |= (onestat >> (chip_mode * 16));
+ case 2:
+ res |= (onestat >> (chip_mode * 8));
+ case 1:
+ ;
+ }
+
+ /* Last, determine what the bit-pattern should be for a single
+ device, according to chip mode and endianness... */
+ switch (chip_mode) {
+ case 1:
+ break;
+ case 2:
+ res = cfi16_to_cpu(map, res);
+ break;
+ case 4:
+ res = cfi32_to_cpu(map, res);
+ break;
+ default: BUG();
+ }
+ return res;
+}
+EXPORT_SYMBOL(cfi_merge_status);
+
+/*
+ * Sends a CFI command to a bank of flash for the given geometry.
+ *
+ * Returns the offset in flash where the command was written.
+ * If prev_val is non-null, it will be set to the value at the command address,
+ * before the command was written.
+ */
+uint32_t cfi_send_gen_cmd(u_char cmd, uint32_t cmd_addr, uint32_t base,
+ struct map_info *map, struct cfi_private *cfi,
+ int type, map_word *prev_val)
+{
+ map_word val;
+ uint32_t addr = base + cfi_build_cmd_addr(cmd_addr, map, cfi);
+ val = cfi_build_cmd(cmd, map, cfi);
+
+ if (prev_val)
+ *prev_val = map_read(map, addr);
+
+ map_write(map, val, addr);
+
+ return addr - base;
+}
+EXPORT_SYMBOL(cfi_send_gen_cmd);
+
int __xipram cfi_qry_present(struct map_info *map, __u32 base,
struct cfi_private *cfi)
{