From 3c24121039c9da14692eb48f6e39565b28c0f3cf Mon Sep 17 00:00:00 2001 From: Vladimir Murzin <vladimir.murzin@arm.com> Date: Tue, 3 Apr 2018 10:38:37 +0100 Subject: [PATCH] ARM: 8756/1: NOMMU: Postpone MPU activation till __after_proc_init MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch postpone MPU activation till __after_proc_init (which is placed in .text section) rather than doing it in __setup_mpu. It allows us ignore used-only-once .head.text section while programming PMSAv8 MPU (for PMSAv7 it stays covered anyway). Tested-by: Szemz? András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> --- arch/arm/kernel/head-nommu.S | 45 ++++++++++++++++++------------------ 1 file changed, 22 insertions(+), 23 deletions(-) diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index e294c0aa1e367..2f0f1ba6e2376 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -125,11 +125,24 @@ __secondary_data: */ .text __after_proc_init: +#ifdef CONFIG_ARM_MPU +M_CLASS(movw r12, #:lower16:BASEADDR_V7M_SCB) +M_CLASS(movt r12, #:upper16:BASEADDR_V7M_SCB) +M_CLASS(ldr r3, [r12, 0x50]) +AR_CLASS(mrc p15, 0, r3, c0, c1, 4) @ Read ID_MMFR0 + and r3, r3, #(MMFR0_PMSA) @ PMSA field + teq r3, #(MMFR0_PMSAv7) @ PMSA v7 +#endif #ifdef CONFIG_CPU_CP15 /* * CP15 system control register value returned in r0 from * the CPU init function. */ + +#ifdef CONFIG_ARM_MPU + biceq r0, r0, #CR_BR @ Disable the 'default mem-map' + orreq r0, r0, #CR_M @ Set SCTRL.M (MPU on) +#endif #if defined(CONFIG_ALIGNMENT_TRAP) && __LINUX_ARM_ARCH__ < 6 orr r0, r0, #CR_A #else @@ -145,7 +158,15 @@ __after_proc_init: bic r0, r0, #CR_I #endif mcr p15, 0, r0, c1, c0, 0 @ write control reg + isb #elif defined (CONFIG_CPU_V7M) +#ifdef CONFIG_ARM_MPU + ldreq r3, [r12, MPU_CTRL] + biceq r3, #MPU_CTRL_PRIVDEFENA + orreq r3, #MPU_CTRL_ENABLE + streq r3, [r12, MPU_CTRL] + isb +#endif /* For V7M systems we want to modify the CCR similarly to the SCTLR */ #ifdef CONFIG_CPU_DCACHE_DISABLE bic r0, r0, #V7M_SCB_CCR_DC @@ -156,9 +177,7 @@ __after_proc_init: #ifdef CONFIG_CPU_ICACHE_DISABLE bic r0, r0, #V7M_SCB_CCR_IC #endif - movw r3, #:lower16:(BASEADDR_V7M_SCB + V7M_SCB_CCR) - movt r3, #:upper16:(BASEADDR_V7M_SCB + V7M_SCB_CCR) - str r0, [r3] + str r0, [r12, V7M_SCB_CCR] #endif /* CONFIG_CPU_CP15 elif CONFIG_CPU_V7M */ ret lr ENDPROC(__after_proc_init) @@ -282,19 +301,6 @@ M_CLASS(ldr r0, [r12, #MPU_TYPE]) setup_region r0, r5, r6, PMSAv7_INSTR_SIDE, r12 @ XIP_PHYS_ADDR, shared, enabled 3: isb #endif - - /* Enable the MPU */ -AR_CLASS(mrc p15, 0, r0, c1, c0, 0) @ Read SCTLR -AR_CLASS(bic r0, r0, #CR_BR) @ Disable the 'default mem-map' -AR_CLASS(orr r0, r0, #CR_M) @ Set SCTRL.M (MPU on) -AR_CLASS(mcr p15, 0, r0, c1, c0, 0) @ Enable MPU - -M_CLASS(ldr r0, [r12, #MPU_CTRL]) -M_CLASS(bic r0, #MPU_CTRL_PRIVDEFENA) -M_CLASS(orr r0, #MPU_CTRL_ENABLE) -M_CLASS(str r0, [r12, #MPU_CTRL]) - isb - ret lr ENDPROC(__setup_pmsa_v7) @@ -352,13 +358,6 @@ ENTRY(__secondary_setup_pmsa_v7) cmp r4, #0 bgt 1b - /* Enable the MPU */ - mrc p15, 0, r0, c1, c0, 0 @ Read SCTLR - bic r0, r0, #CR_BR @ Disable the 'default mem-map' - orr r0, r0, #CR_M @ Set SCTRL.M (MPU on) - mcr p15, 0, r0, c1, c0, 0 @ Enable MPU - isb - ret lr ENDPROC(__secondary_setup_pmsa_v7) -- GitLab