[PATCH V2] lib: reset: Move fdt_reset_init into generic_early_init

guoren at kernel.org guoren at kernel.org
Sun Jun 18 08:07:16 PDT 2023


From: Guo Ren <guoren at linux.alibaba.com>

The fdt_reset_thead driver needs to modify the __reset_thead_csr_stub
text region for the secondary harts booting. After that, the
sbi_hart_pmp_configure may lock down the text region with M_READABLE &
M_EXECUTABLE attributes in the future. Currently, the M_READABLE &
M_EXECUtABLE have no effect on m-mode, the L-bit in pmpcfg csr is
useless for the current opensbi scenario. See:

Priv-isa-spec 3.7.1.2. Locking and Privilege Mode
When the L bit is clear, any M-mode access matching the PMP entry will
succeed; the R/W/X permissions apply only to S and U modes.

That's why current fdt_reset_thead could still work well after commit:
230278dcf127 ("lib: sbi: Add separate entries for firmware RX and RW
regions"). So this patch fixes up a fake bug for the M-mode permission
setting of the future.

Fixes: 230278dcf127 ("lib: sbi: Add separate entries for firmware RX and RW regions")
Link: http://lists.infradead.org/pipermail/opensbi/2023-June/005176.html
Reported-by: Jessica Clarke <jrtc27 at jrtc27.com>
Signed-off-by: Guo Ren <guoren at linux.alibaba.com>
Signed-off-by: Guo Ren <guoren at kernel.org>
---
Changelog:
v2:
 - Direct move fdt_reset_init into generic_early_init
---
 platform/generic/platform.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/platform/generic/platform.c b/platform/generic/platform.c
index eeefef4c9533..bd608f6d4065 100644
--- a/platform/generic/platform.c
+++ b/platform/generic/platform.c
@@ -143,6 +143,9 @@ static int generic_nascent_init(void)
 
 static int generic_early_init(bool cold_boot)
 {
+	if (cold_boot)
+		fdt_reset_init();
+
 	if (!generic_plat || !generic_plat->early_init)
 		return 0;
 
@@ -154,9 +157,6 @@ static int generic_final_init(bool cold_boot)
 	void *fdt;
 	int rc;
 
-	if (cold_boot)
-		fdt_reset_init();
-
 	if (generic_plat && generic_plat->final_init) {
 		rc = generic_plat->final_init(cold_boot, generic_plat_match);
 		if (rc)
-- 
2.36.1




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