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
/*
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* IOP Coprocessor-6 access handler
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* Copyright (c) 2006, Intel Corporation.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms and conditions of the GNU General Public License,
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* version 2, as published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
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* Place - Suite 330, Boston, MA 02111-1307 USA.
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*
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*/
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#include <linux/init.h>
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#include <asm/traps.h>
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static int cp6_trap(struct pt_regs *regs, unsigned int instr)
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{
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u32 temp;
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/* enable cp6 access */
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asm volatile (
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"mrc p15, 0, %0, c15, c1, 0\n\t"
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"orr %0, %0, #(1 << 6)\n\t"
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"mcr p15, 0, %0, c15, c1, 0\n\t"
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: "=r"(temp));
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return 0;
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}
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/* permit kernel space cp6 access
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* deny user space cp6 access
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*/
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static struct undef_hook cp6_hook = {
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.instr_mask = 0x0f000ff0,
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.instr_val = 0x0e000610,
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.cpsr_mask = MODE_MASK,
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.cpsr_val = SVC_MODE,
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.fn = cp6_trap,
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};
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void __init iop_init_cp6_handler(void)
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{
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register_undef_hook(&cp6_hook);
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}
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