diff options
Diffstat (limited to 'hw/char')
| -rw-r--r-- | hw/char/pl011.c | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/hw/char/pl011.c b/hw/char/pl011.c index c076813..3fa3b75 100644 --- a/hw/char/pl011.c +++ b/hw/char/pl011.c @@ -81,6 +81,17 @@ static void pl011_update(PL011State *s) } } +static bool pl011_is_fifo_enabled(PL011State *s) +{ + return (s->lcr & 0x10) != 0; +} + +static inline unsigned pl011_get_fifo_depth(PL011State *s) +{ + /* Note: FIFO depth is expected to be power-of-2 */ + return pl011_is_fifo_enabled(s) ? PL011_FIFO_DEPTH : 1; +} + static uint64_t pl011_read(void *opaque, hwaddr offset, unsigned size) { @@ -94,8 +105,7 @@ static uint64_t pl011_read(void *opaque, hwaddr offset, c = s->read_fifo[s->read_pos]; if (s->read_count > 0) { s->read_count--; - if (++s->read_pos == 16) - s->read_pos = 0; + s->read_pos = (s->read_pos + 1) & (pl011_get_fifo_depth(s) - 1); } if (s->read_count == 0) { s->flags |= PL011_FLAG_RXFE; @@ -273,11 +283,7 @@ static int pl011_can_receive(void *opaque) PL011State *s = (PL011State *)opaque; int r; - if (s->lcr & 0x10) { - r = s->read_count < 16; - } else { - r = s->read_count < 1; - } + r = s->read_count < pl011_get_fifo_depth(s); trace_pl011_can_receive(s->lcr, s->read_count, r); return r; } @@ -286,15 +292,15 @@ static void pl011_put_fifo(void *opaque, uint32_t value) { PL011State *s = (PL011State *)opaque; int slot; + unsigned pipe_depth; - slot = s->read_pos + s->read_count; - if (slot >= 16) - slot -= 16; + pipe_depth = pl011_get_fifo_depth(s); + slot = (s->read_pos + s->read_count) & (pipe_depth - 1); s->read_fifo[slot] = value; s->read_count++; s->flags &= ~PL011_FLAG_RXFE; trace_pl011_put_fifo(value, s->read_count); - if (!(s->lcr & 0x10) || s->read_count == 16) { + if (s->read_count == pipe_depth) { trace_pl011_put_fifo_full(); s->flags |= PL011_FLAG_RXFF; } @@ -359,7 +365,7 @@ static const VMStateDescription vmstate_pl011 = { VMSTATE_UINT32(dmacr, PL011State), VMSTATE_UINT32(int_enabled, PL011State), VMSTATE_UINT32(int_level, PL011State), - VMSTATE_UINT32_ARRAY(read_fifo, PL011State, 16), + VMSTATE_UINT32_ARRAY(read_fifo, PL011State, PL011_FIFO_DEPTH), VMSTATE_UINT32(ilpr, PL011State), VMSTATE_UINT32(ibrd, PL011State), VMSTATE_UINT32(fbrd, PL011State), |