diff options
| author | Frederic Konrad <fkonrad@amd.com> | 2023-11-24 14:35:05 +0000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2023-11-27 17:02:04 +0000 |
| commit | 1ee80592bf24eabef77e2260a86d9358b54c08fd (patch) | |
| tree | 2d3b23de480b216809c48242224ca2a58b192d91 | |
| parent | a9bc470ec208bd27a82100abc9dccf1b69f41b45 (diff) | |
hw/dma/xlnx_csu_dma: don't throw guest errors when stopping the SRC DMApull-target-arm-20231127
UG1087 states for the source channel that: if SIZE is programmed to 0, and the
DMA is started, the interrupts DONE and MEM_DONE will be asserted.
This implies that it is allowed for the guest to stop the source DMA by writing
a size of 0 to the SIZE register, so remove the LOG_GUEST_ERROR in that case.
While at it remove the comment marking the SIZE register as write-only.
See: https://docs.xilinx.com/r/en-US/ug1087-zynq-ultrascale-registers/CSUDMA_SRC_SIZE-CSUDMA-Register
Signed-off-by: Frederic Konrad <fkonrad@amd.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@amd.com>
Message-id: 20231124143505.1493184-4-fkonrad@amd.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
| -rw-r--r-- | hw/dma/xlnx_csu_dma.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/hw/dma/xlnx_csu_dma.c b/hw/dma/xlnx_csu_dma.c index 531013f35a..bc1505aade 100644 --- a/hw/dma/xlnx_csu_dma.c +++ b/hw/dma/xlnx_csu_dma.c @@ -39,7 +39,7 @@ REG32(ADDR, 0x0) FIELD(ADDR, ADDR, 2, 30) /* wo */ REG32(SIZE, 0x4) - FIELD(SIZE, SIZE, 2, 27) /* wo */ + FIELD(SIZE, SIZE, 2, 27) FIELD(SIZE, LAST_WORD, 0, 1) /* rw, only exists in SRC */ REG32(STATUS, 0x8) FIELD(STATUS, DONE_CNT, 13, 3) /* wtc */ @@ -335,10 +335,14 @@ static uint64_t addr_pre_write(RegisterInfo *reg, uint64_t val) static uint64_t size_pre_write(RegisterInfo *reg, uint64_t val) { XlnxCSUDMA *s = XLNX_CSU_DMA(reg->opaque); + uint64_t size = val & R_SIZE_SIZE_MASK; if (s->regs[R_SIZE] != 0) { - qemu_log_mask(LOG_GUEST_ERROR, - "%s: Starting DMA while already running.\n", __func__); + if (size || s->is_dst) { + qemu_log_mask(LOG_GUEST_ERROR, + "%s: Starting DMA while already running.\n", + __func__); + } } if (!s->is_dst) { @@ -346,7 +350,7 @@ static uint64_t size_pre_write(RegisterInfo *reg, uint64_t val) } /* Size is word aligned */ - return val & R_SIZE_SIZE_MASK; + return size; } static uint64_t size_post_read(RegisterInfo *reg, uint64_t val) |