1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
The common CFI driver provides this weak default implementation for
flash_cmd_reset():
static void __flash_cmd_reset(flash_info_t *info)
{
/*
* We do not yet know what kind of commandset to use, so we issue
* the reset command in both Intel and AMD variants, in the hope
* that AMD flash roms ignore the Intel command.
*/
flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
udelay(1);
flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
}
void flash_cmd_reset(flash_info_t *info)
__attribute__((weak,alias("__flash_cmd_reset")));
Some flash chips seem to have trouble with this reset sequence.
In this case, board-specific code can override this weak default
version with a board-specific function.
At the time of writing, there are two boards that define their own
routine for this.
First, the digsy_mtc board equipped with the M29W128GH from Numonyx
needs this version to function properly:
void flash_cmd_reset(flash_info_t *info)
{
flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
}
In addition, the t3corp board defines the routine thusly:
void flash_cmd_reset(flash_info_t *info)
{
/*
* FLASH at address CFG_SYS_FLASH_BASE is a Spansion chip and
* needs the Spansion type reset commands. The other flash chip
* is located behind a FPGA (Xilinx DS617) and needs the Intel type
* reset command.
*/
if (info->start[0] == CFG_SYS_FLASH_BASE)
flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
else
flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
}
see also:
http://www.mail-archive.com/u-boot@lists.denx.de/msg24368.html
Config Option
CONFIG_SYS_MAX_FLASH_SECT: Number of sectors available on Flash device
CONFIG_SYS_FLASH_CFI_WIDTH: Data-width of the flash device
CONFIG_CMD_FLASH: Enables Flash command library
CONFIG_FLASH_CFI_DRIVER: Enables CFI Flash driver
CONFIG_FLASH_CFI_MTD: Enables MTD frame work for NOR Flash devices
|
