[PATCH] arm: proc-v7-3level.S: SOC_LS1021A: clear TTBCR.T1SZ

yanjiang.jin at windriver.com yanjiang.jin at windriver.com
Tue May 2 02:47:18 PDT 2017


From: Yanjiang Jin <yanjiang.jin at windriver.com>

The macro "v7_ttb_setup" will set "TTBCR.T1SZ" only when
"PHYS_OFFSET <= PAGE_OFFSET".
But if we load the second kernel during kdump boot, PHYS_OFFSET may be
greater than PAGE_OFFSET, we don't want to set this bit, but TTBCR.T1SZ
is still not zero since the first kernel's value is reserved.
In this circumstance, the second kernel would hang once the MMU is enabled.

Signed-off-by: Yanjiang Jin <yanjiang.jin at windriver.com>
---
 arch/arm/mm/proc-v7-3level.S | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mm/proc-v7-3level.S b/arch/arm/mm/proc-v7-3level.S
index 5e5720e..b6ca5eb 100644
--- a/arch/arm/mm/proc-v7-3level.S
+++ b/arch/arm/mm/proc-v7-3level.S
@@ -140,12 +140,16 @@ ENDPROC(cpu_v7_set_pte_ext)
 	 * otherwise booting secondary CPUs would end up using TTBR1 for the
 	 * identity mapping set up in TTBR0.
 	 */
-	orrls	\tmp, \tmp, #TTBR1_SIZE				@ TTBCR.T1SZ
-	mcr	p15, 0, \tmp, c2, c0, 2				@ TTBCR
+
+#ifdef CONFIG_SOC_LS1021A
+	bic	\tmp, \tmp, #TTBR1_SIZE		@ clear TTBCR.T1SZ first
+#endif
+	orrls	\tmp, \tmp, #TTBR1_SIZE		@ TTBCR.T1SZ
+	mcr	p15, 0, \tmp, c2, c0, 2		@ TTBCR
 	mov	\tmp, \ttbr1, lsr #20
 	mov	\ttbr1, \ttbr1, lsl #12
 	addls	\ttbr1, \ttbr1, #TTBR1_OFFSET
-	mcrr	p15, 1, \ttbr1, \tmp, c2			@ load TTBR1
+	mcrr	p15, 1, \ttbr1, \tmp, c2	@ load TTBR1
 	.endm
 
 	/*
-- 
1.9.1




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