asix-sigma: Cleanup FPGA initialization

Rework the pre-firmware-upload FPGA initialization sequence so it matches
the documentation. Also, since this sequence is documented in a separate
section, wrap it into separate function.

Signed-off-by: Marek Vasut <marex@denx.de>
This commit is contained in:
Marek Vasut 2014-04-20 17:18:31 +02:00 committed by Bert Vermeulen
parent 790c7ccc88
commit d5fa188ac9
1 changed files with 47 additions and 27 deletions

View File

@ -80,16 +80,6 @@ static const int32_t hwcaps[] = {
SR_CONF_LIMIT_SAMPLES,
};
/* Force the FPGA to reboot. */
static uint8_t suicide[] = {
0x84, 0x84, 0x88, 0x84, 0x88, 0x84, 0x88, 0x84,
};
/* Prepare to upload firmware (FPGA specific). */
static uint8_t init_array[] = {
0x03, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
};
/* Initialize the logic analyzer mode. */
static uint8_t logic_mode_start[] = {
0x00, 0x40, 0x0f, 0x25, 0x35, 0x40,
@ -497,6 +487,49 @@ static GSList *dev_list(void)
return ((struct drv_context *)(di->priv))->instances;
}
/*
* Configure the FPGA for bitbang mode.
* This sequence is documented in section 2. of the ASIX Sigma programming
* manual. This sequence is necessary to configure the FPGA in the Sigma
* into Bitbang mode, in which it can be programmed with the firmware.
*/
static int sigma_fpga_init_bitbang(struct dev_context *devc)
{
uint8_t suicide[] = {
0x84, 0x84, 0x88, 0x84, 0x88, 0x84, 0x88, 0x84,
};
uint8_t init_array[] = {
0x01, 0x03, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01,
0x01, 0x01,
};
int i, ret, timeout = 10000;
uint8_t data;
/* Section 2. part 1), do the FPGA suicide. */
sigma_write(suicide, sizeof(suicide), devc);
sigma_write(suicide, sizeof(suicide), devc);
sigma_write(suicide, sizeof(suicide), devc);
sigma_write(suicide, sizeof(suicide), devc);
/* Section 2. part 2), do pulse on D1. */
sigma_write(init_array, sizeof(init_array), devc);
ftdi_usb_purge_buffers(&devc->ftdic);
/* Wait until the FPGA asserts D6/INIT_B. */
for (i = 0; i < timeout; i++) {
ret = sigma_read(&data, 1, devc);
if (ret < 0)
return ret;
/* Test if pin D6 got asserted. */
if (data & (1 << 5))
return 0;
/* The D6 was not asserted yet, wait a bit. */
usleep(10000);
}
return SR_ERR_TIMEOUT;
}
static int upload_firmware(int firmware_idx, struct dev_context *devc)
{
int ret;
@ -527,23 +560,10 @@ static int upload_firmware(int firmware_idx, struct dev_context *devc)
return 0;
}
/* Force the FPGA to reboot. */
sigma_write(suicide, sizeof(suicide), devc);
sigma_write(suicide, sizeof(suicide), devc);
sigma_write(suicide, sizeof(suicide), devc);
sigma_write(suicide, sizeof(suicide), devc);
/* Prepare to upload firmware (FPGA specific). */
sigma_write(init_array, sizeof(init_array), devc);
ftdi_usb_purge_buffers(&devc->ftdic);
/* Wait until the FPGA asserts INIT_B. */
while (1) {
ret = sigma_read(result, 1, devc);
if (result[0] & 0x20)
break;
}
/* Initialize the FPGA for firmware upload. */
ret = sigma_fpga_init_bitbang(devc);
if (ret)
return ret;
/* Prepare firmware. */
snprintf(firmware_path, sizeof(firmware_path), "%s/%s", FIRMWARE_DIR,