linux/arch/arm/mach-omap2/omap-smc.S
Tony Lindgren 351b7c4907 ARM: omap2+: Revert omap-smp.c changes resetting CPU1 during boot
Commit 3251885285 ("ARM: OMAP4+: Reset CPU1 properly for kexec") started
unconditionally resetting CPU1 because of a kexec boot issue I was seeing
earlier on omap4 when doing kexec boot between two different kernel
versions.

This caused issues on some systems. We should only reset CPU1 as a last
resort option, and try to avoid it where possible. Doing an unconditional
CPU1 reset causes issues for example when booting a bootloader configured
secure OS running on CPU1 as reported by Andrew F. Davis <afd@ti.com>.

We can't completely remove the reset of CPU1 as it would break kexec
booting from older kernels. But we can limit the CPU1 reset to cases
where CPU1 is wrongly parked within the memory area used by the booting
kernel. Then later on we can add support for parking CPU1 for kexec out
of the SDRAM back to bootrom.

So let's first fix the regression reported by Andrew by making CPU1 reset
conditional. To do this, we need to:

1. Save configured AUX_CORE_BOOT_1 for later

2. Modify AUX_CORE_BOOT_0 reading code to for HS SoCs to return
   the whole register instead of the CPU mask

3. Check if CPU1 is wrongly parked into the booting kernel by the
   previous kernel and reset if needed

Fixes: 3251885285 ("ARM: OMAP4+: Reset CPU1 properly for kexec")
Reported-by: Andrew F. Davis <afd@ti.com>
Cc: Andrew F. Davis <afd@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Tested-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-03-27 10:10:42 -07:00

99 lines
2.5 KiB
ArmAsm

/*
* OMAP34xx and OMAP44xx secure APIs file.
*
* Copyright (C) 2010 Texas Instruments, Inc.
* Written by Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* Copyright (C) 2012 Ivaylo Dimitrov <freemangordon@abv.bg>
* Copyright (C) 2013 Pali Rohár <pali.rohar@gmail.com>
*
* This program is free software,you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
/*
* This is common routine to manage secure monitor API
* used to modify the PL310 secure registers.
* 'r0' contains the value to be modified and 'r12' contains
* the monitor API number. It uses few CPU registers
* internally and hence they need be backed up including
* link register "lr".
* Function signature : void omap_smc1(u32 fn, u32 arg)
*/
ENTRY(omap_smc1)
stmfd sp!, {r2-r12, lr}
mov r12, r0
mov r0, r1
dsb
smc #0
ldmfd sp!, {r2-r12, pc}
ENDPROC(omap_smc1)
/**
* u32 omap_smc2(u32 id, u32 falg, u32 pargs)
* Low level common routine for secure HAL and PPA APIs.
* @id: Application ID of HAL APIs
* @flag: Flag to indicate the criticality of operation
* @pargs: Physical address of parameter list starting
* with number of parametrs
*/
ENTRY(omap_smc2)
stmfd sp!, {r4-r12, lr}
mov r3, r2
mov r2, r1
mov r1, #0x0 @ Process ID
mov r6, #0xff
mov r12, #0x00 @ Secure Service ID
mov r7, #0
mcr p15, 0, r7, c7, c5, 6
dsb
dmb
smc #0
ldmfd sp!, {r4-r12, pc}
ENDPROC(omap_smc2)
/**
* u32 omap_smc3(u32 service_id, u32 process_id, u32 flag, u32 pargs)
* Low level common routine for secure HAL and PPA APIs via smc #1
* r0 - @service_id: Secure Service ID
* r1 - @process_id: Process ID
* r2 - @flag: Flag to indicate the criticality of operation
* r3 - @pargs: Physical address of parameter list
*/
ENTRY(omap_smc3)
stmfd sp!, {r4-r11, lr}
mov r12, r0 @ Copy the secure service ID
mov r6, #0xff @ Indicate new Task call
dsb @ Memory Barrier (not sure if needed, copied from omap_smc2)
smc #1 @ Call PPA service
ldmfd sp!, {r4-r11, pc}
ENDPROC(omap_smc3)
ENTRY(omap_modify_auxcoreboot0)
stmfd sp!, {r1-r12, lr}
ldr r12, =0x104
dsb
smc #0
ldmfd sp!, {r1-r12, pc}
ENDPROC(omap_modify_auxcoreboot0)
ENTRY(omap_auxcoreboot_addr)
stmfd sp!, {r2-r12, lr}
ldr r12, =0x105
dsb
smc #0
ldmfd sp!, {r2-r12, pc}
ENDPROC(omap_auxcoreboot_addr)
ENTRY(omap_read_auxcoreboot0)
stmfd sp!, {r2-r12, lr}
ldr r12, =0x103
dsb
smc #0
ldmfd sp!, {r2-r12, pc}
ENDPROC(omap_read_auxcoreboot0)