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| author | Rob Herring <rob.herring@linaro.org> | 2014-03-18 13:18:40 -0500 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2014-03-18 19:38:55 +0000 |
| commit | ce8f0905a59232982c8a220169e11c14c73e7dea (patch) | |
| tree | 821ac781cd68fdd8beca82c136d5ec1e10005f61 /hw | |
| parent | 22709e90a270a36418f1b1d5d3277016eec1edc2 (diff) | |
| download | qemu-ce8f0905a59232982c8a220169e11c14c73e7dea.zip | |
pl011: fix UARTRSR accesses corrupting the UARTCR value
Offset 4 is UARTRSR/UARTECR, not the UARTCR. The UARTCR would be
corrupted if the UARTRSR is ever written. Fix by implementing a correct
model of the UARTRSR/UARTECR register. Reads of this register simply
reflect the error bits in data register. Only breaks can be triggered in
QEMU. With the pl011_can_receive function, we effectively have flow
control between the host and the model. Framing and parity errors simply
don't make sense in the model and will never occur.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1395166721-15716-3-git-send-email-robherring2@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/char/pl011.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/hw/char/pl011.c b/hw/char/pl011.c index 8103e2eeb0..11c3a75fc1 100644 --- a/hw/char/pl011.c +++ b/hw/char/pl011.c @@ -20,6 +20,7 @@ typedef struct PL011State { uint32_t readbuff; uint32_t flags; uint32_t lcr; + uint32_t rsr; uint32_t cr; uint32_t dmacr; uint32_t int_enabled; @@ -81,13 +82,14 @@ static uint64_t pl011_read(void *opaque, hwaddr offset, } if (s->read_count == s->read_trigger - 1) s->int_level &= ~ PL011_INT_RX; + s->rsr = c >> 8; pl011_update(s); if (s->chr) { qemu_chr_accept_input(s->chr); } return c; - case 1: /* UARTCR */ - return 0; + case 1: /* UARTRSR */ + return s->rsr; case 6: /* UARTFR */ return s->flags; case 8: /* UARTILPR */ @@ -146,8 +148,8 @@ static void pl011_write(void *opaque, hwaddr offset, s->int_level |= PL011_INT_TX; pl011_update(s); break; - case 1: /* UARTCR */ - s->cr = value; + case 1: /* UARTRSR/UARTECR */ + s->rsr = 0; break; case 6: /* UARTFR */ /* Writes to Flag register are ignored. */ @@ -247,13 +249,14 @@ static const MemoryRegionOps pl011_ops = { static const VMStateDescription vmstate_pl011 = { .name = "pl011", - .version_id = 1, - .minimum_version_id = 1, - .minimum_version_id_old = 1, + .version_id = 2, + .minimum_version_id = 2, + .minimum_version_id_old = 2, .fields = (VMStateField[]) { VMSTATE_UINT32(readbuff, PL011State), VMSTATE_UINT32(flags, PL011State), VMSTATE_UINT32(lcr, PL011State), + VMSTATE_UINT32(rsr, PL011State), VMSTATE_UINT32(cr, PL011State), VMSTATE_UINT32(dmacr, PL011State), VMSTATE_UINT32(int_enabled, PL011State), |