esp: apply transfer length adjustment when STC is zero at TC load time

Perform the length adjustment whereby a value of 0 in the STC represents
a transfer length of 0x10000 at the point where the TC is loaded at the
start of a DMA command rather than just when a TI (Transfer Information)
command is executed. This better matches the description as given in the
datasheet.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210304221103.6369-12-mark.cave-ayland@ilande.co.uk>
This commit is contained in:
Mark Cave-Ayland 2021-03-04 22:10:32 +00:00
parent c04ed569b0
commit 96676c2f74

View file

@ -561,9 +561,6 @@ static void handle_ti(ESPState *s)
}
dmalen = esp_get_tc(s);
if (dmalen == 0) {
dmalen = 0x10000;
}
s->dma_counter = dmalen;
if (s->do_cmd) {
@ -698,7 +695,11 @@ void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
if (val & CMD_DMA) {
s->dma = 1;
/* Reload DMA counter. */
esp_set_tc(s, esp_get_stc(s));
if (esp_get_stc(s) == 0) {
esp_set_tc(s, 0x10000);
} else {
esp_set_tc(s, esp_get_stc(s));
}
} else {
s->dma = 0;
}