arch/arm64: allow floating-point registers access

BRANCH=None
BUG=None
TEST=build coreboot, make sure there are fmov instructions
     generated by the compiler, and boot to kernel

Change-Id: Ia99c710be77d5baec7a743a726257ef3ec782635
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: f770a436a0692c8e57a8c80860a180330b71e82c
Original-Change-Id: Iab4ba979b483d19fe92b8a75d9b881a57985eed7
Original-Signed-off-by: Yen Lin <yelin@nvidia.com>
Original-Signed-off-by: Furquan Shaikh <furquan@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/262242
Original-Tested-by: Furquan Shaikh <furquan@chromium.org>
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9884
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
This commit is contained in:
Yen Lin 2015-03-24 11:15:10 -07:00 committed by Patrick Georgi
parent f7c5c610a2
commit 900059a223
2 changed files with 41 additions and 0 deletions

View File

@ -117,6 +117,25 @@ static void init_this_cpu(void *arg)
printk(BIOS_DEBUG, "%s init\n", dev_path(dev));
dev->ops->init(dev);
}
/*
* Disable coprocessor traps to EL3:
* TCPAC [20] = 0, disable traps for EL2 accesses to CPTR_EL2 or HCPTR
* and EL2/EL1 access to CPACR_EL1.
* TTA [20] = 0, disable traps for trace register access from any EL.
* TFP [10] = 0, disable traps for floating-point instructions from any
* EL.
*/
raw_write_cptr_el3(CPTR_EL3_TCPAC_DISABLE | CPTR_EL3_TTA_DISABLE |
CPTR_EL3_TFP_DISABLE);
/*
* Allow FPU accesses:
* FPEN [21:20] = 3, disable traps for floating-point instructions from
* EL0/EL1.
* TTA [28] = 0, disable traps for trace register access from EL0/EL1.
*/
raw_write_cpacr_el1(CPACR_TRAP_FP_DISABLE | CPACR_TTA_DISABLE);
}
/* Fill in cpu_info structures according to device tree. */

View File

@ -126,6 +126,28 @@
#define SCTLR_LITTLE_END (0 << SCTLR_ENDIAN_SHIFT)
#define SCTLR_BIG_END (1 << SCTLR_ENDIAN_SHIFT)
#define CPTR_EL3_TCPAC_SHIFT (31)
#define CPTR_EL3_TTA_SHIFT (20)
#define CPTR_EL3_TFP_SHIFT (10)
#define CPTR_EL3_TCPAC_DISABLE (0 << CPTR_EL3_TCPAC_SHIFT)
#define CPTR_EL3_TCPAC_ENABLE (1 << CPTR_EL3_TCPAC_SHIFT)
#define CPTR_EL3_TTA_DISABLE (0 << CPTR_EL3_TTA_SHIFT)
#define CPTR_EL3_TTA_ENABLE (1 << CPTR_EL3_TTA_SHIFT)
#define CPTR_EL3_TFP_DISABLE (0 << CPTR_EL3_TFP_SHIFT)
#define CPTR_EL3_TFP_ENABLE (1 << CPTR_EL3_TFP_SHIFT)
#define CPACR_TTA_SHIFT (28)
#define CPACR_TTA_ENABLE (1 << CPACR_TTA_SHIFT)
#define CPACR_TTA_DISABLE (0 << CPACR_TTA_SHIFT)
#define CPACR_FPEN_SHIFT (20)
/*
* ARMv8-A spec: Values 0b00 and 0b10 both seem to enable traps from el0 and el1
* for fp reg access.
*/
#define CPACR_TRAP_FP_EL0_EL1 (0 << CPACR_FPEN_SHIFT)
#define CPACR_TRAP_FP_EL0 (1 << CPACR_FPEN_SHIFT)
#define CPACR_TRAP_FP_DISABLE (3 << CPACR_FPEN_SHIFT)
#ifdef __ASSEMBLY__
/* Macro to switch to label based on current el */