[PATCH v3 7/8] remoteproc: qcom: Add support for memory sandbox

[Srinivasa Rao Mandadapu]

Update pil driver with SMMU mapping for allowing authorised
memory access to ADSP firmware, by reading required memory
regions either from device tree file or from resource table
embedded in ADSP binary header.

Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@xxxxxxxxxxx>
---
Changes since V2:
	-- Replace platform_bus_type with adsp->dev->bus.
	-- Use API of_parse_phandle_with_args() instead of of_parse_phandle_with_fixed_args().
	-- Replace adsp->is_wpss with adsp->is_adsp.
	-- Update error handling in adsp_start().

 drivers/remoteproc/qcom_q6v5_adsp.c | 107 +++++++++++++++++++++++++++++++++++-
 1 file changed, 105 insertions(+), 2 deletions(-)

diff --git a/drivers/remoteproc/qcom_q6v5_adsp.c b/drivers/remoteproc/qcom_q6v5_adsp.c
index f2945bf..b9cafe2 100644
--- a/drivers/remoteproc/qcom_q6v5_adsp.c
+++ b/drivers/remoteproc/qcom_q6v5_adsp.c
@@ -9,6 +9,7 @@
 #include <linux/firmware.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iommu.h>
 #include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/mfd/syscon.h>
@@ -48,6 +49,8 @@
 #define LPASS_PWR_ON_REG		0x10
 #define LPASS_HALTREQ_REG		0x0
 
+#define SID_MASK_DEFAULT        0xF
+
 #define QDSP6SS_XO_CBCR		0x38
 #define QDSP6SS_CORE_CBCR	0x20
 #define QDSP6SS_SLEEP_CBCR	0x3c
@@ -78,7 +81,7 @@ struct adsp_pil_data {
 struct qcom_adsp {
 	struct device *dev;
 	struct rproc *rproc;
-
+	struct iommu_domain *iommu_dom;
 	struct qcom_q6v5 q6v5;
 
 	struct clk *xo;
@@ -333,6 +336,94 @@ static int adsp_load(struct rproc *rproc, const struct firmware *fw)
 	return 0;
 }
 
+static int adsp_map_smmu(struct qcom_adsp *adsp, struct rproc *rproc)
+{
+	struct of_phandle_args args;
+	struct fw_rsc_devmem *rsc_fw;
+	struct fw_rsc_hdr *hdr;
+	const __be32 *prop;
+	long long sid;
+	unsigned long mem_phys;
+	unsigned long iova;
+	unsigned int mem_size;
+	unsigned int flag;
+	unsigned int len;
+	int access_level;
+	int offset;
+	int ret;
+	int rc;
+	int i;
+
+	rc = of_parse_phandle_with_args(adsp->dev->of_node, "iommus", "#iommu-cells", 0, &args);
+	if (rc < 0)
+		sid = -1;
+	else
+		sid = args.args[0] & SID_MASK_DEFAULT;
+
+	adsp->iommu_dom = iommu_domain_alloc(adsp->dev->bus);
+	if (!adsp->iommu_dom) {
+		dev_err(adsp->dev, "failed to allocate iommu domain\n");
+		return -ENOMEM;
+	}
+
+	ret = iommu_attach_device(adsp->iommu_dom, adsp->dev);
+	if (ret) {
+		dev_err(adsp->dev, "could not attach device ret = %d\n", ret);
+		return -EBUSY;
+	}
+
+	/* Add SID configuration for ADSP Firmware to SMMU */
+	adsp->mem_phys =  adsp->mem_phys | (sid << 32);
+
+	ret = iommu_map(adsp->iommu_dom, adsp->mem_phys, adsp->mem_phys,
+			adsp->mem_size,	IOMMU_READ | IOMMU_WRITE);
+	if (ret) {
+		dev_err(adsp->dev, "Unable to map ADSP Physical Memory\n");
+		return ret;
+	}
+
+	prop = of_get_property(adsp->dev->of_node, "qcom,adsp-memory-regions", &len);
+	if (prop) {
+		len /= sizeof(__be32);
+		for (i = 0; i < len; i++) {
+			iova = be32_to_cpu(prop[i++]);
+			mem_phys = be32_to_cpu(prop[i++]);
+			mem_size = be32_to_cpu(prop[i++]);
+			access_level = be32_to_cpu(prop[i]);
+
+			if (access_level)
+				flag = IOMMU_READ | IOMMU_WRITE;
+			else
+				flag = IOMMU_READ;
+
+			ret = iommu_map(adsp->iommu_dom, iova, mem_phys, mem_size, flag);
+			if (ret) {
+				dev_err(adsp->dev, "failed to map addr = %p mem_size = %x\n",
+						&(mem_phys), mem_size);
+				return ret;
+			}
+		}
+	} else {
+		if (!rproc->table_ptr)
+			return 0;
+
+		for (i = 0; i < rproc->table_ptr->num; i++) {
+			offset = rproc->table_ptr->offset[i];
+			hdr = (void *)rproc->table_ptr + offset;
+			rsc_fw = (struct fw_rsc_devmem *)hdr + sizeof(*hdr);
+
+			ret = iommu_map(rproc->domain, rsc_fw->da, rsc_fw->pa,
+						rsc_fw->len, rsc_fw->flags);
+			if (ret) {
+				pr_err("%s; unable to map adsp memory address\n", __func__);
+				return ret;
+			}
+		}
+	}
+	return 0;
+}
+
+
 static int adsp_start(struct rproc *rproc)
 {
 	struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
@@ -343,9 +434,16 @@ static int adsp_start(struct rproc *rproc)
 	if (ret)
 		return ret;
 
+	if (adsp->is_adsp_sb_needed) {
+		ret = adsp_map_smmu(adsp, rproc);
+		if (ret) {
+			dev_err(adsp->dev, "ADSP smmu mapping failed\n");
+			goto disable_irqs;
+		}
+	}
 	ret = clk_prepare_enable(adsp->xo);
 	if (ret)
-		goto disable_irqs;
+		goto adsp_smmu_unmap;
 
 	ret = qcom_rproc_pds_enable(adsp, adsp->proxy_pds,
 				    adsp->proxy_pd_count);
@@ -401,6 +499,11 @@ static int adsp_start(struct rproc *rproc)
 	qcom_rproc_pds_disable(adsp, adsp->proxy_pds, adsp->proxy_pd_count);
 disable_xo_clk:
 	clk_disable_unprepare(adsp->xo);
+adsp_smmu_unmap:
+	if (adsp->is_adsp_sb_needed) {
+		iommu_unmap(adsp->iommu_dom, adsp->mem_phys, adsp->mem_size);
+		iommu_domain_free(adsp->iommu_dom);
+	}
 disable_irqs:
 	qcom_q6v5_unprepare(&adsp->q6v5);
 
-- 
2.7.4