diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2014-06-29 18:38:40 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2014-06-29 18:38:40 +0100 |
| commit | ab7a0f0b6dbe8836d490c736803abef6e3695e1f (patch) | |
| tree | 731672c6bbe31834c2e9010c4dc547fdee7d2a25 /hw | |
| parent | ed657d7117d751dfaf5b00e5b17e45cd4a6d974d (diff) | |
hw/arm/pxa2xx_gpio: Fix handling of GPSR/GPCR reads
The PXA2xx GPIO GPSR and GPCR registers are write-only, with reads being
undefined behaviour. Instead of having GPCR return 31337 and GPSR return
the value last written, make both log the guest error and return 0.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/arm/pxa2xx_gpio.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/hw/arm/pxa2xx_gpio.c b/hw/arm/pxa2xx_gpio.c index 7f75f05137..cd506dfd1a 100644 --- a/hw/arm/pxa2xx_gpio.c +++ b/hw/arm/pxa2xx_gpio.c @@ -36,7 +36,6 @@ struct PXA2xxGPIOInfo { uint32_t rising[PXA2XX_GPIO_BANKS]; uint32_t falling[PXA2XX_GPIO_BANKS]; uint32_t status[PXA2XX_GPIO_BANKS]; - uint32_t gpsr[PXA2XX_GPIO_BANKS]; uint32_t gafr[PXA2XX_GPIO_BANKS * 2]; uint32_t prev_level[PXA2XX_GPIO_BANKS]; @@ -162,14 +161,14 @@ static uint64_t pxa2xx_gpio_read(void *opaque, hwaddr offset, return s->dir[bank]; case GPSR: /* GPIO Pin-Output Set registers */ - printf("%s: Read from a write-only register " REG_FMT "\n", - __FUNCTION__, offset); - return s->gpsr[bank]; /* Return last written value. */ + qemu_log_mask(LOG_GUEST_ERROR, + "pxa2xx GPIO: read from write only register GPSR\n"); + return 0; case GPCR: /* GPIO Pin-Output Clear registers */ - printf("%s: Read from a write-only register " REG_FMT "\n", - __FUNCTION__, offset); - return 31337; /* Specified as unpredictable in the docs. */ + qemu_log_mask(LOG_GUEST_ERROR, + "pxa2xx GPIO: read from write only register GPCR\n"); + return 0; case GRER: /* GPIO Rising-Edge Detect Enable registers */ return s->rising[bank]; @@ -217,7 +216,6 @@ static void pxa2xx_gpio_write(void *opaque, hwaddr offset, case GPSR: /* GPIO Pin-Output Set registers */ s->olevel[bank] |= value; pxa2xx_gpio_handler_update(s); - s->gpsr[bank] = value; break; case GPCR: /* GPIO Pin-Output Clear registers */ |