[PATCH v4 1/3] fdtdec: optionally add property no-map to created reserved memory node

[Patrice Chotard]

From: Etienne Carriere <etienne.carriere at st.com>

Add boolean input argument @no_map to helper function
fdtdec_add_reserved_memory() to add or not "no-map" property
for an added reserved memory node.

Property no-map is used by the Linux kernel to not not map memory
in its static memory mapping. It is needed for example for the|
consistency of system non-cached memory and to prevent speculative
accesses to some firewalled memory.

No functional change. A later change will update to OPTEE library to
add no-map property to OP-TEE reserved memory nodes.

Signed-off-by: Etienne Carriere <etienne.carriere at st.com>
Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
---

Changes in v4:
   - Reword commit message

Changes in v2:
   - fix dm fdtdec test and arch/riscv/lib/fdt_fixup.c with
   fdtdec_add_reserved_memory() new parameter

 arch/riscv/lib/fdt_fixup.c |  2 +-
 include/fdtdec.h           |  5 +++--
 lib/fdtdec.c               | 10 ++++++++--
 lib/optee/optee.c          |  2 +-
 test/dm/fdtdec.c           |  6 +++---
 5 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/riscv/lib/fdt_fixup.c b/arch/riscv/lib/fdt_fixup.c
index 5b2420243f..d02062fd5b 100644
--- a/arch/riscv/lib/fdt_fixup.c
+++ b/arch/riscv/lib/fdt_fixup.c
@@ -75,7 +75,7 @@ int riscv_fdt_copy_resv_mem_node(const void *src, void *dst)
 		pmp_mem.start = addr;
 		pmp_mem.end = addr + size - 1;
 		err = fdtdec_add_reserved_memory(dst, basename, &pmp_mem,
-						 &phandle);
+						 &phandle, false);
 		if (err < 0 && err != -FDT_ERR_EXISTS) {
 			log_err("failed to add reserved memory: %d\n", err);
 			return err;
diff --git a/include/fdtdec.h b/include/fdtdec.h
index 152eb07b9e..62d1660973 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -1029,7 +1029,7 @@ static inline int fdtdec_set_phandle(void *blob, int node, uint32_t phandle)
  *     };
  *     uint32_t phandle;
  *
- *     fdtdec_add_reserved_memory(fdt, "framebuffer", &fb, &phandle);
+ *     fdtdec_add_reserved_memory(fdt, "framebuffer", &fb, &phandle, false);
  *
  * This results in the following subnode being added to the top-level
  * /reserved-memory node:
@@ -1056,11 +1056,12 @@ static inline int fdtdec_set_phandle(void *blob, int node, uint32_t phandle)
  * @param carveout	information about the carveout region
  * @param phandlep	return location for the phandle of the carveout region
  *			can be NULL if no phandle should be added
+ * @param no_map	add "no-map" property if true
  * @return 0 on success or a negative error code on failure
  */
 int fdtdec_add_reserved_memory(void *blob, const char *basename,
 			       const struct fdt_memory *carveout,
-			       uint32_t *phandlep);
+			       uint32_t *phandlep, bool no_map);
 
 /**
  * fdtdec_get_carveout() - reads a carveout from an FDT
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index d3b22ec323..b3cbe1223e 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -1319,7 +1319,7 @@ static int fdtdec_init_reserved_memory(void *blob)
 
 int fdtdec_add_reserved_memory(void *blob, const char *basename,
 			       const struct fdt_memory *carveout,
-			       uint32_t *phandlep)
+			       uint32_t *phandlep, bool no_map)
 {
 	fdt32_t cells[4] = {}, *ptr = cells;
 	uint32_t upper, lower, phandle;
@@ -1419,6 +1419,12 @@ int fdtdec_add_reserved_memory(void *blob, const char *basename,
 	if (err < 0)
 		return err;
 
+	if (no_map) {
+		err = fdt_setprop(blob, node, "no-map", NULL, 0);
+		if (err < 0)
+			return err;
+	}
+
 	/* return the phandle for the new node for the caller to use */
 	if (phandlep)
 		*phandlep = phandle;
@@ -1484,7 +1490,7 @@ int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
 	fdt32_t value;
 	void *prop;
 
-	err = fdtdec_add_reserved_memory(blob, name, carveout, &phandle);
+	err = fdtdec_add_reserved_memory(blob, name, carveout, &phandle, false);
 	if (err < 0) {
 		debug("failed to add reserved memory: %d\n", err);
 		return err;
diff --git a/lib/optee/optee.c b/lib/optee/optee.c
index 457d4cca8a..963c2ff430 100644
--- a/lib/optee/optee.c
+++ b/lib/optee/optee.c
@@ -192,7 +192,7 @@ int optee_copy_fdt_nodes(const void *old_blob, void *new_blob)
 				ret = fdtdec_add_reserved_memory(new_blob,
 								 nodename,
 								 &carveout,
-								 NULL);
+								 NULL, false);
 				free(oldname);
 
 				if (ret < 0)
diff --git a/test/dm/fdtdec.c b/test/dm/fdtdec.c
index 716993f706..4119003041 100644
--- a/test/dm/fdtdec.c
+++ b/test/dm/fdtdec.c
@@ -80,7 +80,7 @@ static int dm_test_fdtdec_add_reserved_memory(struct unit_test_state *uts)
 	resv.start = 0x1000;
 	resv.end = 0x1fff;
 	ut_assertok(fdtdec_add_reserved_memory(blob, "rsvd_region",
-					       &resv, &phandle));
+					       &resv, &phandle, false));
 
 	/* Test /reserve-memory and its subnode should exist */
 	parent = fdt_path_offset(blob, "/reserved-memory");
@@ -101,7 +101,7 @@ static int dm_test_fdtdec_add_reserved_memory(struct unit_test_state *uts)
 	resv.start = 0x2000;
 	resv.end = 0x2fff;
 	ut_assertok(fdtdec_add_reserved_memory(blob, "rsvd_region1",
-					       &resv, &phandle1));
+					       &resv, &phandle1, false));
 	subnode = fdt_path_offset(blob, "/reserved-memory/rsvd_region1");
 	ut_assert(subnode > 0);
 
@@ -115,7 +115,7 @@ static int dm_test_fdtdec_add_reserved_memory(struct unit_test_state *uts)
 	resv.start = 0x1000;
 	resv.end = 0x1fff;
 	ut_assertok(fdtdec_add_reserved_memory(blob, "rsvd_region2",
-					       &resv, &phandle1));
+					       &resv, &phandle1, false));
 	subnode = fdt_path_offset(blob, "/reserved-memory/rsvd_region2");
 	ut_assert(subnode < 0);
 
-- 
2.17.1