altos: Speed up at45 and 25lc erase speeds
authorKeith Packard <keithp@keithp.com>
Sat, 8 Jan 2011 01:54:54 +0000 (17:54 -0800)
committerKeith Packard <keithp@keithp.com>
Sat, 8 Jan 2011 01:54:54 +0000 (17:54 -0800)
No need to read the block to be erased before erasing it.

Signed-off-by: Keith Packard <keithp@keithp.com>
src/ao_ee.c
src/ao_flash.c

index 7de05b7..e3b4110 100644 (file)
@@ -19,6 +19,7 @@
 #include "25lc1024.h"
 
 #define EE_BLOCK_SIZE  ((uint16_t) (256))
+#define EE_BLOCK_SHIFT 8
 #define EE_DEVICE_SIZE ((uint32_t) 128 * (uint32_t) 1024)
 
 /* Total bytes of available storage */
@@ -166,7 +167,7 @@ ao_ee_fill(uint16_t block)
 uint8_t
 ao_storage_device_write(uint32_t pos, __xdata void *buf, uint16_t len) __reentrant
 {
-       uint16_t block = (uint16_t) (pos >> 8);
+       uint16_t block = (uint16_t) (pos >> EE_BLOCK_SHIFT);
 
        /* Transfer the data */
        ao_mutex_get(&ao_ee_mutex); {
@@ -185,7 +186,7 @@ ao_storage_device_write(uint32_t pos, __xdata void *buf, uint16_t len) __reentra
 uint8_t
 ao_storage_device_read(uint32_t pos, __xdata void *buf, uint16_t len) __reentrant
 {
-       uint16_t block = (uint16_t) (pos >> 8);
+       uint16_t block = (uint16_t) (pos >> EE_BLOCK_SHIFT);
 
        /* Transfer the data */
        ao_mutex_get(&ao_ee_mutex); {
@@ -207,8 +208,8 @@ uint8_t
 ao_storage_erase(uint32_t pos) __reentrant
 {
        ao_mutex_get(&ao_ee_mutex); {
-               uint16_t block = (uint16_t) (pos >> 8);
-               ao_ee_fill(block);
+               ao_ee_flush_internal();
+               ao_ee_block = (uint16_t) (pos >> EE_BLOCK_SHIFT);
                memset(ao_ee_data, 0xff, EE_BLOCK_SIZE);
                ao_ee_block_dirty = 1;
        } ao_mutex_put(&ao_ee_mutex);
index 1201a0e..3a264ce 100644 (file)
@@ -289,10 +289,9 @@ ao_storage_flush(void) __reentrant
 uint8_t
 ao_storage_erase(uint32_t pos) __reentrant
 {
-       uint16_t block = (uint16_t) (pos >> ao_flash_block_shift);
-
        ao_mutex_get(&ao_flash_mutex); {
-               ao_flash_fill(block);
+               ao_flash_flush_internal();
+               ao_flash_block = (uint16_t) (pos >> ao_flash_block_shift);
                memset(ao_flash_data, 0xff, ao_flash_block_size);
                ao_flash_block_dirty = 1;
        } ao_mutex_put(&ao_flash_mutex);