esp: Do not overwrite ESP_TCHI after reset
PATCH 1/1 esp: Do not overwrite ESP_TCHI after reset
After a reset ESP_TCHI should contain the unique ID of the chip. This value will be overwritten with the current tranfer count if the transfer count has previously been set.
The code never checks if the transfer count has been set, so the unique ID will always be overwritten if the driver sends a DMA NOP after reset.
--- hw/scsi/esp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
hw/scsi/esp.c +3 -1
@@ -454,7 +454,9 @@ void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)/* Reload DMA counter. */ s->rregs[ESP_TCLO ] = s->wregs[ESP_TCLO ]; s->rregs[ESP_TCMID ] = s->wregs[ESP_TCMID ]; - s->rregs[ESP_TCHI ] = s->wregs[ESP_TCHI ]; +if (s->wregs[ESP_TCHI ]) { + s->rregs[ESP_TCHI ] = s->wregs[ESP_TCHI ]; + } }else { s->dma =0 ; }
Signature · 1 line
1.7.12.4
Quoted 19 lines · Hannes Reinecke
After a reset
ESP_TCHIshould contain the unique ID of the chip. This value will be overwritten with the current tranfer count if the transfer count has previously been set.
The code never checks if the transfer count has been set, so the unique ID will always be overwritten if the driver sends a DMA NOP after reset.Signed-off-by Hannes Reinecke <[email protected]>--- hw/scsi/esp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)hw/scsi/esp.c +0
-0
hw/scsi/esp.c void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val) · line 462
Quoted 10 lines
hw/scsi/esp.c +3
-1@@ -454,7 +454,9 @@ void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)/* Reload DMA counter. */ s->rregs[ESP_TCLO ] = s->wregs[ESP_TCLO ]; s->rregs[ESP_TCMID ] = s->wregs[ESP_TCMID ]; - s->rregs[ESP_TCHI ] = s->wregs[ESP_TCHI ]; +if (s->wregs[ESP_TCHI ]) { + s->rregs[ESP_TCHI ] = s->wregs[ESP_TCHI ]; + } }else { s->dma =0 ; }
Hmm.
This is actually not quite correct.
I'll be sending an updated patch.
Cheers,
Hannes
Signature · 4 lines
Dr. Hannes Reinecke zSeries & Storage [email protected] +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 21284 (AG Nürnberg)