hw/dma: sifive_pdma: Fix Control.claim bit detection

At present the codes detect whether the DMA channel is claimed by:

  claimed = !!s->chan[ch].control & CONTROL_CLAIM;

As ! has higher precedence over & (bitwise and), this is essentially

  claimed = (!!s->chan[ch].control) & CONTROL_CLAIM;

which is wrong, as any non-zero bit set in the control register will
produce a result of a claimed channel.

Fixes: de7c7988d25d ("hw/dma: sifive_pdma: reset Next* registers when Control.claim is set")
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210927072124.1564129-1-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/hw/dma/sifive_pdma.c b/hw/dma/sifive_pdma.c
index b4fd40573a5cc74f6331883d5694775cefcb282f..b8ec7621f31ecaa6f42612a633b7ff3f6b8390ef 100644 (file)
--- a/hw/dma/sifive_pdma.c
+++ b/hw/dma/sifive_pdma.c
@@ -243,7 +243,7 @@ static void sifive_pdma_write(void *opaque, hwaddr offset,
     offset &= 0xfff;
     switch (offset) {
     case DMA_CONTROL:
-        claimed = !!s->chan[ch].control & CONTROL_CLAIM;
+        claimed = !!(s->chan[ch].control & CONTROL_CLAIM);
 
         if (!claimed && (value & CONTROL_CLAIM)) {
             /* reset Next* registers */