redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

ARM: 8527/1: virt: enable GICv3 system registers 

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>
hifive-unleashed-5.1
Jean-Philippe Brucker 2016-02-15 20:16:24 +01:00 committed by Russell King
parent 64ac2e74f0
commit e59941b9b3
1 changed files with 24 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
arch/arm/kernel/hyp-stub.S
View File

@ -17,6 +17,7 @@
*/
#include <linux/init.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/virt.h>
@ -159,6 +160,29 @@ ARM_BE8(orr r7, r7, #(1 << 25)) @ HSCTLR.EE
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.