mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-25 02:48:21 +00:00
588ef76935
Enable svc access to cp6 via an undefined instruction hook. Do not enable access for usr code. This patch also makes iop13xx select PLAT_IOP, this requires a small change to drivers/i2c/busses/i2c-iop3xx.c. Per Lennert Buytenhek's note, the cp6 trap routine is moved to arch/arm/plat-iop Per Nicolas Pitre's note, the cp_wait is skipped since the latency to return to the faulting function is longer than cp_wait. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
51 lines
1.4 KiB
C
51 lines
1.4 KiB
C
/*
|
|
* IOP Coprocessor-6 access handler
|
|
* Copyright (c) 2006, Intel Corporation.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope 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., 59 Temple
|
|
* Place - Suite 330, Boston, MA 02111-1307 USA.
|
|
*
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <asm/traps.h>
|
|
|
|
static int cp6_trap(struct pt_regs *regs, unsigned int instr)
|
|
{
|
|
u32 temp;
|
|
|
|
/* enable cp6 access */
|
|
asm volatile (
|
|
"mrc p15, 0, %0, c15, c1, 0\n\t"
|
|
"orr %0, %0, #(1 << 6)\n\t"
|
|
"mcr p15, 0, %0, c15, c1, 0\n\t"
|
|
: "=r"(temp));
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* permit kernel space cp6 access
|
|
* deny user space cp6 access
|
|
*/
|
|
static struct undef_hook cp6_hook = {
|
|
.instr_mask = 0x0f000ff0,
|
|
.instr_val = 0x0e000610,
|
|
.cpsr_mask = MODE_MASK,
|
|
.cpsr_val = SVC_MODE,
|
|
.fn = cp6_trap,
|
|
};
|
|
|
|
void __init iop_init_cp6_handler(void)
|
|
{
|
|
register_undef_hook(&cp6_hook);
|
|
}
|