| Message ID | 1448961299-15161-5-git-send-email-stanimir.varbanov@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Dec 01, 2015 at 11:14:59AM +0200, Stanimir Varbanov wrote: > 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> > --- > .../devicetree/bindings/dma/qcom_bam_dma.txt | 2 ++ > drivers/dma/qcom_bam_dma.c | 7 +++++++ > 2 files changed, 9 insertions(+) > > diff --git a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt > index 1c9d48ea4914..87b6b2bf5e1e 100644 > --- a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt > +++ b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt > @@ -13,6 +13,8 @@ Required properties: > - clock-names: must contain "bam_clk" entry > - qcom,ee : indicates the active Execution Environment identifier (0-7) used in > the secure world. > +- qcom,controlled-remotely : optional, indicates that the bam is controled by > + remote proccessor i.e. execution enviroment. Please fix the spelling. controlled, environment. Otherwise looks ok. > > Example: > > diff --git a/drivers/dma/qcom_bam_dma.c b/drivers/dma/qcom_bam_dma.c > index 6d290de9ab2b..5dedab77180a 100644 > --- a/drivers/dma/qcom_bam_dma.c > +++ b/drivers/dma/qcom_bam_dma.c > @@ -387,6 +387,7 @@ struct bam_device { > > /* execution environment ID, from DT */ > u32 ee; > + bool controlled_remotely; > > const struct reg_offset_data *layout; > > @@ -1039,6 +1040,9 @@ static int bam_init(struct bam_device *bdev) > 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)); > @@ -1126,6 +1130,9 @@ static int bam_dma_probe(struct platform_device *pdev) > 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); Reviewed-by: Andy Gross <agross@codeaurora.org>
diff --git a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt index 1c9d48ea4914..87b6b2bf5e1e 100644 --- a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt +++ b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt @@ -13,6 +13,8 @@ Required properties: - clock-names: must contain "bam_clk" entry - qcom,ee : indicates the active Execution Environment identifier (0-7) used in the secure world. +- qcom,controlled-remotely : optional, indicates that the bam is controled by + remote proccessor i.e. execution enviroment. Example: diff --git a/drivers/dma/qcom_bam_dma.c b/drivers/dma/qcom_bam_dma.c index 6d290de9ab2b..5dedab77180a 100644 --- a/drivers/dma/qcom_bam_dma.c +++ b/drivers/dma/qcom_bam_dma.c @@ -387,6 +387,7 @@ struct bam_device { /* execution environment ID, from DT */ u32 ee; + bool controlled_remotely; const struct reg_offset_data *layout; @@ -1039,6 +1040,9 @@ static int bam_init(struct bam_device *bdev) 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)); @@ -1126,6 +1130,9 @@ static int bam_dma_probe(struct platform_device *pdev) 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);
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> --- .../devicetree/bindings/dma/qcom_bam_dma.txt | 2 ++ drivers/dma/qcom_bam_dma.c | 7 +++++++ 2 files changed, 9 insertions(+)