[PATCH] mmu: explicitly map executable non-SDRAM regions with MAP_CODE

[PATCH] mmu: explicitly map executable non-SDRAM regions with MAP_CODE

[Ahmad Fatoum]

So far we have been setting eXecute Never on MAP_UNCACHED regions and
left it out for the default MAP_CACHED region.

We have at least three places, which depend on this to remap non-SDRAM
regions executable, so ROM code or newly uploaded code can be run.

Switch them over to use a new MAP_CODE mapping type. For now, this is
equivalent to MAP_CACHED, but with the addition of W^X support in
barebox, this will be required to avoid a prefetch abort when MMU
attributes are used.

Signed-off-by: Ahmad Fatoum <a.fatoum@barebox.org>
---
Sascha, I think this should be ordered before your MMU patches to avoid
the known regressions. Let's see what else there is. :)
---
 arch/arm/mach-imx/romapi.c | 3 ++-
 drivers/firmware/socfpga.c | 3 ++-
 drivers/hab/habv4.c        | 2 +-
 include/mmu.h              | 1 +
 4 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-imx/romapi.c b/arch/arm/mach-imx/romapi.c
index 10af42f28a76..a4143d372ae8 100644
--- a/arch/arm/mach-imx/romapi.c
+++ b/arch/arm/mach-imx/romapi.c
@@ -299,7 +299,8 @@ void imx93_bootsource(void)
 		goto out;
 	}
 
-	arch_remap_range((void *)rom.start, rom.start, resource_size(&rom), MAP_CACHED);
+	/* TODO: restore uncached mapping once we no longer need this? */
+	arch_remap_range((void *)rom.start, rom.start, resource_size(&rom), MAP_CODE);
 
 	OPTIMIZER_HIDE_VAR(rom_api);
 
diff --git a/drivers/firmware/socfpga.c b/drivers/firmware/socfpga.c
index 0f7d11abb588..4b10ca009798 100644
--- a/drivers/firmware/socfpga.c
+++ b/drivers/firmware/socfpga.c
@@ -353,7 +353,8 @@ static int socfpga_fpgamgr_program_finish(struct firmware_handler *fh)
 		return status;
 	}
 
-	remap_range((void *)CYCLONE5_OCRAM_ADDRESS, PAGE_SIZE, MAP_CACHED);
+	/* TODO: restore uncached mapping once we no longer need this? */
+	remap_range((void *)CYCLONE5_OCRAM_ADDRESS, PAGE_SIZE, MAP_CODE);
 
 	dev_dbg(&mgr->dev, "Setting APPLYCFG bit...\n");
 
diff --git a/drivers/hab/habv4.c b/drivers/hab/habv4.c
index 4945e8930acb..83ee06a6aa46 100644
--- a/drivers/hab/habv4.c
+++ b/drivers/hab/habv4.c
@@ -689,7 +689,7 @@ int imx8m_hab_print_status(void)
 
 int imx6_hab_print_status(void)
 {
-	remap_range(0x0, SZ_1M, MAP_CACHED);
+	remap_range(0x0, SZ_1M, MAP_CODE);
 
 	imx6_hab_get_status();
 
diff --git a/include/mmu.h b/include/mmu.h
index 84ec6c5efb3e..669959050194 100644
--- a/include/mmu.h
+++ b/include/mmu.h
@@ -8,6 +8,7 @@
 #define MAP_UNCACHED	0
 #define MAP_CACHED	1
 #define MAP_FAULT	2
+#define MAP_CODE	MAP_CACHED	/* until support added */
 
 /*
  * Depending on the architecture the default mapping can be
-- 
2.39.5