drivers/spi/spi_flash: don't allocate unbounded stack memory

This open-codes flash_cmd, but until the API is fixed for real, it uses
xfer's existing scatter-gather ability to write command and data in one
go.

BUG=chromium:446201
TEST=emerge-coral coreboot succeeds

Change-Id: Ic81b7c9f7e0f2647e59b81d61abd68d36051e578
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://review.coreboot.org/28254
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
This commit is contained in:
Patrick Georgi 2018-08-21 11:46:31 -04:00
parent e166ea4d2a
commit c5ee35ff86
1 changed files with 15 additions and 10 deletions

View File

@ -82,24 +82,29 @@ static int spi_flash_cmd_read(const struct spi_slave *spi, const u8 *cmd,
return ret;
}
/* TODO: This code is quite possibly broken and overflowing stacks. Fix ASAP! */
#pragma GCC diagnostic push
#if defined(__GNUC__) && !defined(__clang__)
#pragma GCC diagnostic ignored "-Wstack-usage="
#endif
int spi_flash_cmd_write(const struct spi_slave *spi, const u8 *cmd,
size_t cmd_len, const void *data, size_t data_len)
{
int ret;
u8 buff[cmd_len + data_len];
memcpy(buff, cmd, cmd_len);
memcpy(buff + cmd_len, data, data_len);
int ret = 1;
struct spi_op vectors[] = {
[0] = { .dout = cmd, .bytesout = cmd_len,
.din = NULL, .bytesin = 0, },
[1] = { .dout = data, .bytesout = data_len,
.din = NULL, .bytesin = 0, }
};
size_t count = ARRAY_SIZE(vectors);
if (spi_claim_bus(spi))
return ret;
if (spi_xfer_vector(spi, vectors, count) == 0)
ret = 0;
ret = do_spi_flash_cmd(spi, buff, cmd_len + data_len, NULL, 0);
if (ret) {
printk(BIOS_WARNING, "SF: Failed to send write command (%zu bytes): %d\n",
data_len, ret);
}
spi_release_bus(spi);
return ret;
}