Commit c6213c6c authored by Steven J. Hill's avatar Steven J. Hill Committed by Ralf Baechle
Browse files

MIPS: microMIPS: Fix improper definition of ISA exception bit. 



The ISA exception bit selects whether exceptions are taken in classic
or microMIPS mode. This bit is Config3.ISAOnExc and was improperly
defined as bits 16 and 17 instead of just bit 16. A new function was
added so that platforms could set this bit when running a kernel
compiled with only microMIPS instructions.

Signed-off-by: default avatarSteven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5377/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent fe6d2909

arch/mips/include/asm/mipsregs.h

+1 −1
Original line number Diff line number Diff line
@@ -596,7 +596,7 @@ 
#define MIPS_CONF3_RXI		(_ULCAST_(1) << 12)

#define MIPS_CONF3_ULRI		(_ULCAST_(1) << 13)

#define MIPS_CONF3_ISA		(_ULCAST_(3) << 14)

#define MIPS_CONF3_ISA_OE	(_ULCAST_(3) << 16)

#define MIPS_CONF3_ISA_OE	(_ULCAST_(1) << 16)

#define MIPS_CONF3_VZ		(_ULCAST_(1) << 23)



#define MIPS_CONF4_MMUSIZEEXT	(_ULCAST_(255) << 0)

arch/mips/kernel/cpu-probe.c

+0 −3
Original line number Diff line number Diff line
@@ -269,9 +269,6 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c) 
		c->options |= MIPS_CPU_ULRI;

	if (config3 & MIPS_CONF3_ISA)

		c->options |= MIPS_CPU_MICROMIPS;

#ifdef CONFIG_CPU_MICROMIPS

	write_c0_config3(read_c0_config3() | MIPS_CONF3_ISA_OE);

#endif

	if (config3 & MIPS_CONF3_VZ)

		c->ases |= MIPS_ASE_VZ;

arch/mips/kernel/traps.c

+9 −0
Original line number Diff line number Diff line
@@ -1878,6 +1878,15 @@ void __init trap_init(void) 
			ebase += (read_c0_ebase() & 0x3ffff000);

	}



	if (cpu_has_mmips) {

		unsigned int config3 = read_c0_config3();



		if (IS_ENABLED(CONFIG_CPU_MICROMIPS))

			write_c0_config3(config3 | MIPS_CONF3_ISA_OE);

		else

			write_c0_config3(config3 & ~MIPS_CONF3_ISA_OE);

	}



	if (board_ebase_setup)

		board_ebase_setup();

	per_cpu_trap_init(true);

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