mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-28 03:40:04 +00:00
e59941b9b3
ARMv8 introduces system registers for the Generic Interrupt Controllers CPU and virtual interfaces. When GICv3 is implemented, EL2 needs to allow the kernel to use those registers, by changing the value of ICC_HSRE. Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
246 lines
6.8 KiB
ArmAsm
246 lines
6.8 KiB
ArmAsm
/*
|
|
* Copyright (c) 2012 Linaro Limited.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/irqchip/arm-gic-v3.h>
|
|
#include <linux/linkage.h>
|
|
#include <asm/assembler.h>
|
|
#include <asm/virt.h>
|
|
|
|
#ifndef ZIMAGE
|
|
/*
|
|
* For the kernel proper, we need to find out the CPU boot mode long after
|
|
* boot, so we need to store it in a writable variable.
|
|
*
|
|
* This is not in .bss, because we set it sufficiently early that the boot-time
|
|
* zeroing of .bss would clobber it.
|
|
*/
|
|
.data
|
|
ENTRY(__boot_cpu_mode)
|
|
.long 0
|
|
.text
|
|
|
|
/*
|
|
* Save the primary CPU boot mode. Requires 3 scratch registers.
|
|
*/
|
|
.macro store_primary_cpu_mode reg1, reg2, reg3
|
|
mrs \reg1, cpsr
|
|
and \reg1, \reg1, #MODE_MASK
|
|
adr \reg2, .L__boot_cpu_mode_offset
|
|
ldr \reg3, [\reg2]
|
|
str \reg1, [\reg2, \reg3]
|
|
.endm
|
|
|
|
/*
|
|
* Compare the current mode with the one saved on the primary CPU.
|
|
* If they don't match, record that fact. The Z bit indicates
|
|
* if there's a match or not.
|
|
* Requires 3 additionnal scratch registers.
|
|
*/
|
|
.macro compare_cpu_mode_with_primary mode, reg1, reg2, reg3
|
|
adr \reg2, .L__boot_cpu_mode_offset
|
|
ldr \reg3, [\reg2]
|
|
ldr \reg1, [\reg2, \reg3]
|
|
cmp \mode, \reg1 @ matches primary CPU boot mode?
|
|
orrne \reg1, \reg1, #BOOT_CPU_MODE_MISMATCH
|
|
strne \reg1, [\reg2, \reg3] @ record what happened and give up
|
|
.endm
|
|
|
|
#else /* ZIMAGE */
|
|
|
|
.macro store_primary_cpu_mode reg1:req, reg2:req, reg3:req
|
|
.endm
|
|
|
|
/*
|
|
* The zImage loader only runs on one CPU, so we don't bother with mult-CPU
|
|
* consistency checking:
|
|
*/
|
|
.macro compare_cpu_mode_with_primary mode, reg1, reg2, reg3
|
|
cmp \mode, \mode
|
|
.endm
|
|
|
|
#endif /* ZIMAGE */
|
|
|
|
/*
|
|
* Hypervisor stub installation functions.
|
|
*
|
|
* These must be called with the MMU and D-cache off.
|
|
* They are not ABI compliant and are only intended to be called from the kernel
|
|
* entry points in head.S.
|
|
*/
|
|
@ Call this from the primary CPU
|
|
ENTRY(__hyp_stub_install)
|
|
store_primary_cpu_mode r4, r5, r6
|
|
ENDPROC(__hyp_stub_install)
|
|
|
|
@ fall through...
|
|
|
|
@ Secondary CPUs should call here
|
|
ENTRY(__hyp_stub_install_secondary)
|
|
mrs r4, cpsr
|
|
and r4, r4, #MODE_MASK
|
|
|
|
/*
|
|
* If the secondary has booted with a different mode, give up
|
|
* immediately.
|
|
*/
|
|
compare_cpu_mode_with_primary r4, r5, r6, r7
|
|
retne lr
|
|
|
|
/*
|
|
* Once we have given up on one CPU, we do not try to install the
|
|
* stub hypervisor on the remaining ones: because the saved boot mode
|
|
* is modified, it can't compare equal to the CPSR mode field any
|
|
* more.
|
|
*
|
|
* Otherwise...
|
|
*/
|
|
|
|
cmp r4, #HYP_MODE
|
|
retne lr @ give up if the CPU is not in HYP mode
|
|
|
|
/*
|
|
* Configure HSCTLR to set correct exception endianness/instruction set
|
|
* state etc.
|
|
* Turn off all traps
|
|
* Eventually, CPU-specific code might be needed -- assume not for now
|
|
*
|
|
* This code relies on the "eret" instruction to synchronize the
|
|
* various coprocessor accesses. This is done when we switch to SVC
|
|
* (see safe_svcmode_maskall).
|
|
*/
|
|
@ Now install the hypervisor stub:
|
|
adr r7, __hyp_stub_vectors
|
|
mcr p15, 4, r7, c12, c0, 0 @ set hypervisor vector base (HVBAR)
|
|
|
|
@ Disable all traps, so we don't get any nasty surprise
|
|
mov r7, #0
|
|
mcr p15, 4, r7, c1, c1, 0 @ HCR
|
|
mcr p15, 4, r7, c1, c1, 2 @ HCPTR
|
|
mcr p15, 4, r7, c1, c1, 3 @ HSTR
|
|
|
|
THUMB( orr r7, #(1 << 30) ) @ HSCTLR.TE
|
|
ARM_BE8(orr r7, r7, #(1 << 25)) @ HSCTLR.EE
|
|
mcr p15, 4, r7, c1, c0, 0 @ HSCTLR
|
|
|
|
mrc p15, 4, r7, c1, c1, 1 @ HDCR
|
|
and r7, #0x1f @ Preserve HPMN
|
|
mcr p15, 4, r7, c1, c1, 1 @ HDCR
|
|
|
|
#if !defined(ZIMAGE) && defined(CONFIG_ARM_ARCH_TIMER)
|
|
@ make CNTP_* and CNTPCT accessible from PL1
|
|
mrc p15, 0, r7, c0, c1, 1 @ ID_PFR1
|
|
lsr r7, #16
|
|
and r7, #0xf
|
|
cmp r7, #1
|
|
bne 1f
|
|
mrc p15, 4, r7, c14, c1, 0 @ CNTHCTL
|
|
orr r7, r7, #3 @ PL1PCEN | PL1PCTEN
|
|
mcr p15, 4, r7, c14, c1, 0 @ CNTHCTL
|
|
mov r7, #0
|
|
mcrr p15, 4, r7, r7, c14 @ CNTVOFF
|
|
|
|
@ Disable virtual timer in case it was counting
|
|
mrc p15, 0, r7, c14, c3, 1 @ CNTV_CTL
|
|
bic r7, #1 @ Clear ENABLE
|
|
mcr p15, 0, r7, c14, c3, 1 @ CNTV_CTL
|
|
1:
|
|
#endif
|
|
|
|
#ifdef CONFIG_ARM_GIC_V3
|
|
@ Check whether GICv3 system registers are available
|
|
mrc p15, 0, r7, c0, c1, 1 @ ID_PFR1
|
|
ubfx r7, r7, #28, #4
|
|
cmp r7, #1
|
|
bne 2f
|
|
|
|
@ Enable system register accesses
|
|
mrc p15, 4, r7, c12, c9, 5 @ ICC_HSRE
|
|
orr r7, r7, #(ICC_SRE_EL2_ENABLE | ICC_SRE_EL2_SRE)
|
|
mcr p15, 4, r7, c12, c9, 5 @ ICC_HSRE
|
|
isb
|
|
|
|
@ SRE bit could be forced to 0 by firmware.
|
|
@ Check whether it sticks before accessing any other sysreg
|
|
mrc p15, 4, r7, c12, c9, 5 @ ICC_HSRE
|
|
tst r7, #ICC_SRE_EL2_SRE
|
|
beq 2f
|
|
mov r7, #0
|
|
mcr p15, 4, r7, c12, c11, 0 @ ICH_HCR
|
|
2:
|
|
#endif
|
|
|
|
bx lr @ The boot CPU mode is left in r4.
|
|
ENDPROC(__hyp_stub_install_secondary)
|
|
|
|
__hyp_stub_do_trap:
|
|
cmp r0, #-1
|
|
mrceq p15, 4, r0, c12, c0, 0 @ get HVBAR
|
|
mcrne p15, 4, r0, c12, c0, 0 @ set HVBAR
|
|
__ERET
|
|
ENDPROC(__hyp_stub_do_trap)
|
|
|
|
/*
|
|
* __hyp_set_vectors: Call this after boot to set the initial hypervisor
|
|
* vectors as part of hypervisor installation. On an SMP system, this should
|
|
* be called on each CPU.
|
|
*
|
|
* r0 must be the physical address of the new vector table (which must lie in
|
|
* the bottom 4GB of physical address space.
|
|
*
|
|
* r0 must be 32-byte aligned.
|
|
*
|
|
* Before calling this, you must check that the stub hypervisor is installed
|
|
* everywhere, by waiting for any secondary CPUs to be brought up and then
|
|
* checking that BOOT_CPU_MODE_HAVE_HYP(__boot_cpu_mode) is true.
|
|
*
|
|
* If not, there is a pre-existing hypervisor, some CPUs failed to boot, or
|
|
* something else went wrong... in such cases, trying to install a new
|
|
* hypervisor is unlikely to work as desired.
|
|
*
|
|
* When you call into your shiny new hypervisor, sp_hyp will contain junk,
|
|
* so you will need to set that to something sensible at the new hypervisor's
|
|
* initialisation entry point.
|
|
*/
|
|
ENTRY(__hyp_get_vectors)
|
|
mov r0, #-1
|
|
ENDPROC(__hyp_get_vectors)
|
|
@ fall through
|
|
ENTRY(__hyp_set_vectors)
|
|
__HVC(0)
|
|
ret lr
|
|
ENDPROC(__hyp_set_vectors)
|
|
|
|
#ifndef ZIMAGE
|
|
.align 2
|
|
.L__boot_cpu_mode_offset:
|
|
.long __boot_cpu_mode - .
|
|
#endif
|
|
|
|
.align 5
|
|
__hyp_stub_vectors:
|
|
__hyp_stub_reset: W(b) .
|
|
__hyp_stub_und: W(b) .
|
|
__hyp_stub_svc: W(b) .
|
|
__hyp_stub_pabort: W(b) .
|
|
__hyp_stub_dabort: W(b) .
|
|
__hyp_stub_trap: W(b) __hyp_stub_do_trap
|
|
__hyp_stub_irq: W(b) .
|
|
__hyp_stub_fiq: W(b) .
|
|
ENDPROC(__hyp_stub_vectors)
|
|
|