Re: [PATCH RFT] arm64: dts: qcom: sm8350: Reenable crypto & cryptobam

[Luca Weiss]

On Mon Jan 8, 2024 at 3:18 PM CET, Konrad Dybcio wrote:
> On 8.01.2024 14:49, Luca Weiss wrote:
> > When num-channels and qcom,num-ees is not provided in devicetree, the
> > driver will try to read these values from the registers during probe but
> > this fails if the interconnect is not on and then crashes the system.
> > 
> > So we can provide these properties in devicetree (queried after patching
> > BAM driver to enable the necessary interconnect) so we can probe
> > cryptobam without reading registers and then also use the QCE as
> > expected.
>
> This really feels a bit backwards.. Enable the resource to query the
> hardware for numbers, so that said resource can be enabled, but
> slightly later :/

If you think adding interconnect support to driver and dtsi is better,
let me know.

Stephan (+CC) mentioned it should be okay like this *shrug*

For the record, this is the same way I got the values for sc7280[0] and
sm6350[1].

[0] https://lore.kernel.org/linux-arm-msm/20231229-sc7280-cryptobam-fixup-v1-1-bd8f68589b80@xxxxxxxxxxxxx/
[1] https://lore.kernel.org/linux-arm-msm/20240105-sm6350-qce-v1-0-416e5c7319ac@xxxxxxxxxxxxx/

diff --git a/arch/arm64/boot/dts/qcom/sm8350.dtsi b/arch/arm64/boot/dts/qcom/sm8350.dtsi
index b46236235b7f..cd4dd9852d9e 100644
--- a/arch/arm64/boot/dts/qcom/sm8350.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8350.dtsi
@@ -1756,8 +1756,8 @@ cryptobam: dma-controller@1dc4000 {
 			qcom,controlled-remotely;
 			iommus = <&apps_smmu 0x594 0x0011>,
 				 <&apps_smmu 0x596 0x0011>;
-			/* FIXME: Probing BAM DMA causes some abort and system hang */
-			status = "fail";
+			interconnects = <&aggre2_noc MASTER_CRYPTO 0 &mc_virt SLAVE_EBI1 0>;
+			interconnect-names = "memory";
 		};
 
 		crypto: crypto@1dfa000 {
diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 5e7d332731e0..9de28f615639 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -40,6 +40,7 @@
 #include <linux/circ_buf.h>
 #include <linux/clk.h>
 #include <linux/dmaengine.h>
+#include <linux/interconnect.h>
 #include <linux/pm_runtime.h>
 
 #include "../dmaengine.h"
@@ -394,6 +395,7 @@ struct bam_device {
 	const struct reg_offset_data *layout;
 
 	struct clk *bamclk;
+	struct icc_path *mem_path;
 	int irq;
 
 	/* dma start transaction tasklet */
@@ -1206,6 +1208,7 @@ static int bam_init(struct bam_device *bdev)
 		bdev->num_channels = val & BAM_NUM_PIPES_MASK;
 	}
 
+	printk(KERN_ERR "%s:%d DBG num_ees=%u num_channels=%u\n", __func__, __LINE__, bdev->num_ees, bdev->num_channels);
 	/* Reset BAM now if fully controlled locally */
 	if (!bdev->controlled_remotely && !bdev->powered_remotely)
 		bam_reset(bdev);
@@ -1298,6 +1301,14 @@ static int bam_dma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	bdev->mem_path = devm_of_icc_get(bdev->dev, "memory");
+	if (IS_ERR(bdev->mem_path))
+		return PTR_ERR(bdev->mem_path);
+
+	ret = icc_set_bw(bdev->mem_path, 1, 1);
+	if (ret)
+		return ret;
+
 	ret = bam_init(bdev);
 	if (ret)
 		goto err_disable_clk;