dmaengine: qcom: bam_dma: add controlled-remotely dt property
Some of the peripherals has bam which is controlled by remote
processor, thus the bam dma driver must avoid register writes
which initialise bam hw block. Those registers are protected
from xPU block and any writes to them will lead to secure
violation and system reboot.
Adding the contolled_remotely flag in bam driver to avoid
not permitted register writes in bam_init function.
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Reviewed-by: Andy Gross <andy.gross@linaro.org>
Tested-by: Pramod Gurav <gpramod@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 789d5f8..d0f878a 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -387,6 +387,7 @@
/* execution environment ID, from DT */
u32 ee;
+ bool controlled_remotely;
const struct reg_offset_data *layout;
@@ -1042,6 +1043,9 @@
val = readl_relaxed(bam_addr(bdev, 0, BAM_NUM_PIPES));
bdev->num_channels = val & BAM_NUM_PIPES_MASK;
+ if (bdev->controlled_remotely)
+ return 0;
+
/* s/w reset bam */
/* after reset all pipes are disabled and idle */
val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL));
@@ -1129,6 +1133,9 @@
return ret;
}
+ bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
+ "qcom,controlled-remotely");
+
bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
if (IS_ERR(bdev->bamclk))
return PTR_ERR(bdev->bamclk);