[PATCH v3 5/8] ARM: tegra: Don't apply CPU erratas in insecure mode

From: Dmitry Osipenko
Date: Thu Aug 30 2018 - 14:05:43 EST


CPU isn't allowed to touch secure registers while running under secure
monitor. Hence skip applying of CPU erratas in the reset handler if
Trusted Foundations firmware presents.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
arch/arm/mach-tegra/reset-handler.S | 24 ++++++++++++------------
arch/arm/mach-tegra/reset.c | 3 +++
arch/arm/mach-tegra/reset.h | 9 +++++++--
arch/arm/mach-tegra/sleep-tegra20.S | 4 ++++
4 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/arch/arm/mach-tegra/reset-handler.S b/arch/arm/mach-tegra/reset-handler.S
index 805f306fa6f7..a9f13230da2f 100644
--- a/arch/arm/mach-tegra/reset-handler.S
+++ b/arch/arm/mach-tegra/reset-handler.S
@@ -29,8 +29,6 @@

#define PMC_SCRATCH41 0x140

-#define RESET_DATA(x) ((TEGRA_RESET_##x)*4)
-
#ifdef CONFIG_PM_SLEEP
/*
* tegra_resume
@@ -121,6 +119,12 @@ ENTRY(__tegra_cpu_reset_handler)
cpsid aif, 0x13 @ SVC mode, interrupts disabled

tegra_get_soc_id TEGRA_APB_MISC_BASE, r6
+
+ adr r12, __tegra_cpu_reset_handler_data
+ ldr r5, [r12, #RESET_DATA(TF_PRESENT)]
+ cmp r5, #0
+ bne after_errata
+
#ifdef CONFIG_ARCH_TEGRA_2x_SOC
t20_check:
cmp r6, #TEGRA20
@@ -155,7 +159,6 @@ after_errata:
and r10, r10, #0x3 @ R10 = CPU number
mov r11, #1
mov r11, r11, lsl r10 @ R11 = CPU mask
- adr r12, __tegra_cpu_reset_handler_data

#ifdef CONFIG_SMP
/* Does the OS know about this CPU? */
@@ -169,10 +172,9 @@ after_errata:
cmp r6, #TEGRA20
bne 1f
/* If not CPU0, don't let CPU0 reset CPU1 now that CPU1 is coming up. */
- mov32 r5, TEGRA_IRAM_BASE + TEGRA_IRAM_RESET_HANDLER_OFFSET
mov r0, #CPU_NOT_RESETTABLE
cmp r10, #0
- strneb r0, [r5, #__tegra20_cpu1_resettable_status_offset]
+ strneb r0, [r12, #RESET_DATA(RESETTABLE_STATUS)]
1:
#endif

@@ -277,14 +279,12 @@ ENDPROC(__tegra_cpu_reset_handler)
.align L1_CACHE_SHIFT
.type __tegra_cpu_reset_handler_data, %object
.globl __tegra_cpu_reset_handler_data
+ .globl __tegra_cpu_reset_handler_data_offset
+ .equ __tegra_cpu_reset_handler_data_offset, \
+ . - __tegra_cpu_reset_handler_start
__tegra_cpu_reset_handler_data:
- .rept TEGRA_RESET_DATA_SIZE
- .long 0
+ .rept TEGRA_RESET_DATA_SIZE
+ .long 0
.endr
- .globl __tegra20_cpu1_resettable_status_offset
- .equ __tegra20_cpu1_resettable_status_offset, \
- . - __tegra_cpu_reset_handler_start
- .byte 0
.align L1_CACHE_SHIFT
-
ENTRY(__tegra_cpu_reset_handler_end)
diff --git a/arch/arm/mach-tegra/reset.c b/arch/arm/mach-tegra/reset.c
index dc558892753c..b02ae7699842 100644
--- a/arch/arm/mach-tegra/reset.c
+++ b/arch/arm/mach-tegra/reset.c
@@ -24,6 +24,7 @@
#include <asm/cacheflush.h>
#include <asm/firmware.h>
#include <asm/hardware/cache-l2x0.h>
+#include <asm/trusted_foundations.h>

#include "iomap.h"
#include "irammap.h"
@@ -89,6 +90,8 @@ static void __init tegra_cpu_reset_handler_enable(void)

void __init tegra_cpu_reset_handler_init(void)
{
+ __tegra_cpu_reset_handler_data[TEGRA_RESET_TF_PRESENT] =
+ trusted_foundations_registered();

#ifdef CONFIG_SMP
__tegra_cpu_reset_handler_data[TEGRA_RESET_MASK_PRESENT] =
diff --git a/arch/arm/mach-tegra/reset.h b/arch/arm/mach-tegra/reset.h
index 9c479c7925b8..db0e6b3097ab 100644
--- a/arch/arm/mach-tegra/reset.h
+++ b/arch/arm/mach-tegra/reset.h
@@ -25,7 +25,11 @@
#define TEGRA_RESET_STARTUP_SECONDARY 3
#define TEGRA_RESET_STARTUP_LP2 4
#define TEGRA_RESET_STARTUP_LP1 5
-#define TEGRA_RESET_DATA_SIZE 6
+#define TEGRA_RESET_RESETTABLE_STATUS 6
+#define TEGRA_RESET_TF_PRESENT 7
+#define TEGRA_RESET_DATA_SIZE 8
+
+#define RESET_DATA(x) ((TEGRA_RESET_##x)*4)

#ifndef __ASSEMBLY__

@@ -49,7 +53,8 @@ void __tegra_cpu_reset_handler_end(void);
(u32)__tegra_cpu_reset_handler_start)))
#define tegra20_cpu1_resettable_status \
(IO_ADDRESS(TEGRA_IRAM_BASE + TEGRA_IRAM_RESET_HANDLER_OFFSET + \
- (u32)__tegra20_cpu1_resettable_status_offset))
+ ((u32)&__tegra_cpu_reset_handler_data[TEGRA_RESET_RESETTABLE_STATUS] - \
+ (u32)__tegra_cpu_reset_handler_start)))
#endif

#define tegra_cpu_reset_handler_offset \
diff --git a/arch/arm/mach-tegra/sleep-tegra20.S b/arch/arm/mach-tegra/sleep-tegra20.S
index 5c8e638ee51a..11f423e4a263 100644
--- a/arch/arm/mach-tegra/sleep-tegra20.S
+++ b/arch/arm/mach-tegra/sleep-tegra20.S
@@ -28,6 +28,7 @@
#include <asm/cache.h>

#include "irammap.h"
+#include "reset.h"
#include "sleep.h"

#define EMC_CFG 0xc
@@ -54,6 +55,9 @@
#define APB_MISC_XM2CFGCPADCTRL2 0x8e4
#define APB_MISC_XM2CFGDPADCTRL2 0x8e8

+#define __tegra20_cpu1_resettable_status_offset \
+ (__tegra_cpu_reset_handler_data_offset + RESET_DATA(RESETTABLE_STATUS))
+
.macro pll_enable, rd, r_car_base, pll_base
ldr \rd, [\r_car_base, #\pll_base]
tst \rd, #(1 << 30)
--
2.18.0