[PATCH v3 2/2] remoteproc: qcom_q6v5_mss: Validate each segment during loading

[Bjorn Andersson]

The code used to sync with the MBA after each segment loaded and this is
still what's done downstream. So reduce the delta towards downstream by
switching to a model where the content is iteratively validated.

Reviewed-by: Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx>
Tested-by: Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx>
Tested-by: Luca Weiss <luca@xxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---

Changes since v2:
- Picked up Luca's t-b

 drivers/remoteproc/qcom_q6v5_mss.c | 76 ++++++++++++++++++++----------
 1 file changed, 51 insertions(+), 25 deletions(-)

diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c
index 25c03a26bf88..5eb154f221a4 100644
--- a/drivers/remoteproc/qcom_q6v5_mss.c
+++ b/drivers/remoteproc/qcom_q6v5_mss.c
@@ -360,23 +360,29 @@ static void q6v5_pds_disable(struct q6v5 *qproc, struct device **pds,
 }
 
 static int q6v5_xfer_mem_ownership(struct q6v5 *qproc, int *current_perm,
-				   bool remote_owner, phys_addr_t addr,
+				   bool local, bool remote, phys_addr_t addr,
 				   size_t size)
 {
-	struct qcom_scm_vmperm next;
+	struct qcom_scm_vmperm next[2];
+	int perms = 0;
 
 	if (!qproc->need_mem_protection)
 		return 0;
-	if (remote_owner && *current_perm == BIT(QCOM_SCM_VMID_MSS_MSA))
-		return 0;
-	if (!remote_owner && *current_perm == BIT(QCOM_SCM_VMID_HLOS))
-		return 0;
 
-	next.vmid = remote_owner ? QCOM_SCM_VMID_MSS_MSA : QCOM_SCM_VMID_HLOS;
-	next.perm = remote_owner ? QCOM_SCM_PERM_RW : QCOM_SCM_PERM_RWX;
+	if (local) {
+		next[perms].vmid = QCOM_SCM_VMID_HLOS;
+		next[perms].perm = QCOM_SCM_PERM_RWX;
+		perms++;
+	}
+
+	if (remote) {
+		next[perms].vmid = QCOM_SCM_VMID_MSS_MSA;
+		next[perms].perm = QCOM_SCM_PERM_RW;
+		perms++;
+	}
 
 	return qcom_scm_assign_mem(addr, ALIGN(size, SZ_4K),
-				   current_perm, &next, 1);
+				   current_perm, next, perms);
 }
 
 static int q6v5_load(struct rproc *rproc, const struct firmware *fw)
@@ -693,7 +699,7 @@ static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw)
 
 	/* Hypervisor mapping to access metadata by modem */
 	mdata_perm = BIT(QCOM_SCM_VMID_HLOS);
-	ret = q6v5_xfer_mem_ownership(qproc, &mdata_perm, true, phys, size);
+	ret = q6v5_xfer_mem_ownership(qproc, &mdata_perm, false, true, phys, size);
 	if (ret) {
 		dev_err(qproc->dev,
 			"assigning Q6 access to metadata failed: %d\n", ret);
@@ -711,7 +717,7 @@ static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw)
 		dev_err(qproc->dev, "MPSS header authentication failed: %d\n", ret);
 
 	/* Metadata authentication done, remove modem access */
-	xferop_ret = q6v5_xfer_mem_ownership(qproc, &mdata_perm, false, phys, size);
+	xferop_ret = q6v5_xfer_mem_ownership(qproc, &mdata_perm, true, false, phys, size);
 	if (xferop_ret)
 		dev_warn(qproc->dev,
 			 "mdt buffer not reclaimed system may become unstable\n");
@@ -798,7 +804,7 @@ static int q6v5_mba_load(struct q6v5 *qproc)
 	}
 
 	/* Assign MBA image access in DDR to q6 */
-	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, true,
+	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, false, true,
 				      qproc->mba_phys, qproc->mba_size);
 	if (ret) {
 		dev_err(qproc->dev,
@@ -832,8 +838,8 @@ static int q6v5_mba_load(struct q6v5 *qproc)
 	q6v5proc_halt_axi_port(qproc, qproc->halt_map, qproc->halt_nc);
 
 reclaim_mba:
-	xfermemop_ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, false,
-						qproc->mba_phys,
+	xfermemop_ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, true,
+						false, qproc->mba_phys,
 						qproc->mba_size);
 	if (xfermemop_ret) {
 		dev_err(qproc->dev,
@@ -900,7 +906,7 @@ static void q6v5_mba_reclaim(struct q6v5 *qproc)
 	/* In case of failure or coredump scenario where reclaiming MBA memory
 	 * could not happen reclaim it here.
 	 */
-	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, false,
+	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, true, false,
 				      qproc->mba_phys,
 				      qproc->mba_size);
 	WARN_ON(ret);
@@ -927,6 +933,7 @@ static int q6v5_mpss_load(struct q6v5 *qproc)
 	phys_addr_t boot_addr;
 	phys_addr_t min_addr = PHYS_ADDR_MAX;
 	phys_addr_t max_addr = 0;
+	u32 code_length;
 	bool relocate = false;
 	char *fw_name;
 	size_t fw_name_len;
@@ -977,9 +984,19 @@ static int q6v5_mpss_load(struct q6v5 *qproc)
 	}
 
 	/* Try to reset ownership back to Linux */
-	q6v5_xfer_mem_ownership(qproc, &qproc->mpss_perm, false,
+	q6v5_xfer_mem_ownership(qproc, &qproc->mpss_perm, true, false,
 				qproc->mpss_phys, qproc->mpss_size);
 
+	/* Share ownership between Linux and MSS, during segment loading */
+	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mpss_perm, true, true,
+				      qproc->mpss_phys, qproc->mpss_size);
+	if (ret) {
+		dev_err(qproc->dev,
+			"assigning Q6 access to mpss memory failed: %d\n", ret);
+		ret = -EAGAIN;
+		goto release_firmware;
+	}
+
 	mpss_reloc = relocate ? min_addr : qproc->mpss_phys;
 	qproc->mpss_reloc = mpss_reloc;
 	/* Load firmware segments */
@@ -1028,10 +1045,24 @@ static int q6v5_mpss_load(struct q6v5 *qproc)
 			       phdr->p_memsz - phdr->p_filesz);
 		}
 		size += phdr->p_memsz;
+
+		code_length = readl(qproc->rmb_base + RMB_PMI_CODE_LENGTH_REG);
+		if (!code_length) {
+			boot_addr = relocate ? qproc->mpss_phys : min_addr;
+			writel(boot_addr, qproc->rmb_base + RMB_PMI_CODE_START_REG);
+			writel(RMB_CMD_LOAD_READY, qproc->rmb_base + RMB_MBA_COMMAND_REG);
+		}
+		writel(size, qproc->rmb_base + RMB_PMI_CODE_LENGTH_REG);
+
+		ret = readl(qproc->rmb_base + RMB_MBA_STATUS_REG);
+		if (ret < 0) {
+			dev_err(qproc->dev, "MPSS authentication failed: %d\n", ret);
+			goto release_firmware;
+		}
 	}
 
 	/* Transfer ownership of modem ddr region to q6 */
-	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mpss_perm, true,
+	ret = q6v5_xfer_mem_ownership(qproc, &qproc->mpss_perm, false, true,
 				      qproc->mpss_phys, qproc->mpss_size);
 	if (ret) {
 		dev_err(qproc->dev,
@@ -1040,11 +1071,6 @@ static int q6v5_mpss_load(struct q6v5 *qproc)
 		goto release_firmware;
 	}
 
-	boot_addr = relocate ? qproc->mpss_phys : min_addr;
-	writel(boot_addr, qproc->rmb_base + RMB_PMI_CODE_START_REG);
-	writel(RMB_CMD_LOAD_READY, qproc->rmb_base + RMB_MBA_COMMAND_REG);
-	writel(size, qproc->rmb_base + RMB_PMI_CODE_LENGTH_REG);
-
 	ret = q6v5_rmb_mba_wait(qproc, RMB_MBA_AUTH_COMPLETE, 10000);
 	if (ret == -ETIMEDOUT)
 		dev_err(qproc->dev, "MPSS authentication timed out\n");
@@ -1074,7 +1100,7 @@ static void qcom_q6v5_dump_segment(struct rproc *rproc,
 		if (!ret) {
 			/* Try to reset ownership back to Linux */
 			ret = q6v5_xfer_mem_ownership(qproc, &qproc->mpss_perm,
-						      false,
+						      true, false,
 						      qproc->mpss_phys,
 						      qproc->mpss_size);
 		}
@@ -1116,8 +1142,8 @@ static int q6v5_start(struct rproc *rproc)
 		goto reclaim_mpss;
 	}
 
-	xfermemop_ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, false,
-						qproc->mba_phys,
+	xfermemop_ret = q6v5_xfer_mem_ownership(qproc, &qproc->mba_perm, true,
+						false, qproc->mba_phys,
 						qproc->mba_size);
 	if (xfermemop_ret)
 		dev_err(qproc->dev,
-- 
2.23.0