On 1/8/20 10:14 AM, Ley Foon Tan wrote:
In Cyclone 5 SoC platform, the first USB probing is failed but second probing is success. DWC2 USB driver read gsnpsid register right after de-assert reset, but controller is not ready yet and it returns gsnpsid 0. Polling reset status after de-assert reset to solve the issue.
Retry with this fix more than 10 times without issue.
Signed-off-by: Ley Foon Tan ley.foon.tan@intel.com
v4:
- Change to use get_timer() for timeout.
v3:
- Remove _status callback and poll reset status after deassert reset
- https://patchwork.ozlabs.org/patch/1218026/
v2:
v1:
drivers/reset/reset-socfpga.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/reset/reset-socfpga.c b/drivers/reset/reset-socfpga.c index 93ec9cfdb6..a08967b648 100644 --- a/drivers/reset/reset-socfpga.c +++ b/drivers/reset/reset-socfpga.c @@ -78,9 +78,21 @@ static int socfpga_reset_deassert(struct reset_ctl *reset_ctl) int reg_width = sizeof(u32); int bank = id / (reg_width * BITS_PER_BYTE); int offset = id % (reg_width * BITS_PER_BYTE);
ulong start;
u32 status;
clrbits_le32(data->modrst_base + (bank * BANK_INCREMENT), BIT(offset));
- return 0;
- /* Poll until reset is completed. */
- start = get_timer(0);
- do {
status = readl(data->modrst_base + (bank * BANK_INCREMENT)) &BIT(offset);if (!status)return 0;- } while (get_timer(start) < 200);
- return -ETIMEDOUT;
Isn't this like open-coded wait_for_bit...() ?