[PATCH v1 1/2] firmware: qcom_scm: Remove memory alloc call from qcom_scm_pas_init_image()

[Gokul krishna Krishnakumar]

The memory for metadata is allocated in mdt loader and scm driver

1].  163  data = kmalloc(ehdr_size + hash_size, GFP_KERNEL);
2].  477  mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
     478                                        GFP_KERNEL);

The SCM driver is meant to only pack arguments provided to it from clients
for making the secure world calls. This change removes the logic of doing
a dma alloc coherent from the SCM driver and moves it into the mdt loader

Signed-off-by: Gokul krishna Krishnakumar <quic_gokukris@xxxxxxxxxxx>
---
 drivers/firmware/qcom_scm.c   | 33 +++------------------------------
 drivers/soc/qcom/mdt_loader.c |  3 ++-
 include/linux/qcom_scm.h      |  4 +---
 3 files changed, 6 insertions(+), 34 deletions(-)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index cdbfe54..05ec03c 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -442,11 +442,9 @@ static void qcom_scm_set_download_mode(bool enable)
  *			       state machine for a given peripheral, using the
  *			       metadata
  * @peripheral: peripheral id
- * @metadata:	pointer to memory containing ELF header, program header table
+ * @mdata_phys:	pointer to memory containing ELF header, program header table
  *		and optional blob of data used for authenticating the metadata
  *		and the rest of the firmware
- * @size:	size of the metadata
- * @ctx:	optional metadata context
  *
  * Return: 0 on success.
  *
@@ -454,11 +452,8 @@ static void qcom_scm_set_download_mode(bool enable)
  * track the metadata allocation, this needs to be released by invoking
  * qcom_scm_pas_metadata_release() by the caller.
  */
-int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size,
-			    struct qcom_scm_pas_metadata *ctx)
+int qcom_scm_pas_init_image(u32 peripheral, dma_addr_t mdata_phys)
 {
-	dma_addr_t mdata_phys;
-	void *mdata_buf;
 	int ret;
 	struct qcom_scm_desc desc = {
 		.svc = QCOM_SCM_SVC_PIL,
@@ -469,22 +464,9 @@ int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size,
 	};
 	struct qcom_scm_res res;
 
-	/*
-	 * During the scm call memory protection will be enabled for the meta
-	 * data blob, so make sure it's physically contiguous, 4K aligned and
-	 * non-cachable to avoid XPU violations.
-	 */
-	mdata_buf = dma_alloc_coherent(__scm->dev, size, &mdata_phys,
-				       GFP_KERNEL);
-	if (!mdata_buf) {
-		dev_err(__scm->dev, "Allocation of metadata buffer failed.\n");
-		return -ENOMEM;
-	}
-	memcpy(mdata_buf, metadata, size);
-
 	ret = qcom_scm_clk_enable();
 	if (ret)
-		goto out;
+		return ret;
 
 	ret = qcom_scm_bw_enable();
 	if (ret)
@@ -497,15 +479,6 @@ int qcom_scm_pas_init_image(u32 peripheral, const void *metadata, size_t size,
 	qcom_scm_bw_disable();
 	qcom_scm_clk_disable();
 
-out:
-	if (ret < 0 || !ctx) {
-		dma_free_coherent(__scm->dev, size, mdata_buf, mdata_phys);
-	} else if (ctx) {
-		ctx->ptr = mdata_buf;
-		ctx->phys = mdata_phys;
-		ctx->size = size;
-	}
-
 	return ret ? : res.result[0];
 }
 EXPORT_SYMBOL(qcom_scm_pas_init_image);
diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
index 3f11554..8d06125 100644
--- a/drivers/soc/qcom/mdt_loader.c
+++ b/drivers/soc/qcom/mdt_loader.c
@@ -210,6 +210,7 @@ int qcom_mdt_pas_init(struct device *dev, const struct firmware *fw,
 	const struct elf32_hdr *ehdr;
 	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
+	dma_addr_t mdata_phys;
 	size_t metadata_len;
 	void *metadata;
 	int ret;
@@ -238,7 +239,7 @@ int qcom_mdt_pas_init(struct device *dev, const struct firmware *fw,
 		goto out;
 	}
 
-	ret = qcom_scm_pas_init_image(pas_id, metadata, metadata_len, ctx);
+	ret = qcom_scm_pas_init_image(pas_id, mdata_phys);
 	kfree(metadata);
 	if (ret) {
 		/* Invalid firmware metadata */
diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
index f833564..751436a 100644
--- a/include/linux/qcom_scm.h
+++ b/include/linux/qcom_scm.h
@@ -74,9 +74,7 @@ struct qcom_scm_pas_metadata {
 	ssize_t size;
 };
 
-extern int qcom_scm_pas_init_image(u32 peripheral, const void *metadata,
-				   size_t size,
-				   struct qcom_scm_pas_metadata *ctx);
+extern int qcom_scm_pas_init_image(u32 peripheral, dma_addr_t metadata);
 void qcom_scm_pas_metadata_release(struct qcom_scm_pas_metadata *ctx);
 extern int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr,
 				  phys_addr_t size);
-- 
2.7.4