Commit 06e4814e authored by Huacai Chen's avatar Huacai Chen Committed by Ralf Baechle
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MIPS: Loongson: Invalidate special TLBs when needed 



Loongson-2 has a 4 entry itlb which is a subset of jtlb, Loongson-3 has
a 4 entry itlb and a 4 entry dtlb which are subsets of jtlb. We should
write diag register to invalidate itlb/dtlb when flushing jtlb because
itlb/dtlb are not totally transparent to software.

For Loongson-3A R2 (and newer), we should invalidate ITLB, DTLB, VTLB
and FTLB before we enable/disable FTLB.

Signed-off-by: default avatarHuacai Chen <chenhc@lemote.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Steven J . Hill <sjhill@realitydiluted.com>
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12753/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 37fbe8fa

arch/mips/include/asm/mipsregs.h

+9 −0
Original line number Diff line number Diff line
@@ -780,6 +780,15 @@ 
/* Disable Branch Return Cache */

#define R10K_DIAG_D_BRC		(_ULCAST_(1) << 22)



/* Flush ITLB */

#define LOONGSON_DIAG_ITLB	(_ULCAST_(1) << 2)

/* Flush DTLB */

#define LOONGSON_DIAG_DTLB	(_ULCAST_(1) << 3)

/* Flush VTLB */

#define LOONGSON_DIAG_VTLB	(_ULCAST_(1) << 12)

/* Flush FTLB */

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



/*

 * Coprocessor 1 (FPU) register names

 */

arch/mips/kernel/cpu-probe.c

+3 −0
Original line number Diff line number Diff line
@@ -563,6 +563,9 @@ static int set_ftlb_enable(struct cpuinfo_mips *c, int enable) 
					   << MIPS_CONF7_FTLBP_SHIFT));

		break;

	case CPU_LOONGSON3:

		/* Flush ITLB, DTLB, VTLB and FTLB */

		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB |

			      LOONGSON_DIAG_VTLB | LOONGSON_DIAG_FTLB);

		/* Loongson-3 cores use Config6 to enable the FTLB */

		config = read_c0_config6();

		if (enable)

arch/mips/mm/tlb-r4k.c

+15 −12
Original line number Diff line number Diff line
@@ -28,25 +28,28 @@ 
extern void build_tlb_refill_handler(void);



/*

 * LOONGSON2/3 has a 4 entry itlb which is a subset of dtlb,

 * unfortunately, itlb is not totally transparent to software.

 * LOONGSON-2 has a 4 entry itlb which is a subset of jtlb, LOONGSON-3 has

 * a 4 entry itlb and a 4 entry dtlb which are subsets of jtlb. Unfortunately,

 * itlb/dtlb are not totally transparent to software.

 */

static inline void flush_itlb(void)

static inline void flush_micro_tlb(void)

{

	switch (current_cpu_type()) {

	case CPU_LOONGSON2:

		write_c0_diag(LOONGSON_DIAG_ITLB);

		break;

	case CPU_LOONGSON3:

		write_c0_diag(4);

		write_c0_diag(LOONGSON_DIAG_ITLB | LOONGSON_DIAG_DTLB);

		break;

	default:

		break;

	}

}



static inline void flush_itlb_vm(struct vm_area_struct *vma)

static inline void flush_micro_tlb_vm(struct vm_area_struct *vma)

{

	if (vma->vm_flags & VM_EXEC)

		flush_itlb();

		flush_micro_tlb();

}



void local_flush_tlb_all(void)
@@ -93,7 +96,7 @@ void local_flush_tlb_all(void) 
	tlbw_use_hazard();

	write_c0_entryhi(old_ctx);

	htw_start();

	flush_itlb();

	flush_micro_tlb();

	local_irq_restore(flags);

}

EXPORT_SYMBOL(local_flush_tlb_all);
@@ -159,7 +162,7 @@ void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, 
		} else {

			drop_mmu_context(mm, cpu);

		}

		flush_itlb();

		flush_micro_tlb();

		local_irq_restore(flags);

	}

}
@@ -205,7 +208,7 @@ void local_flush_tlb_kernel_range(unsigned long start, unsigned long end) 
	} else {

		local_flush_tlb_all();

	}

	flush_itlb();

	flush_micro_tlb();

	local_irq_restore(flags);

}
@@ -240,7 +243,7 @@ void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) 
	finish:

		write_c0_entryhi(oldpid);

		htw_start();

		flush_itlb_vm(vma);

		flush_micro_tlb_vm(vma);

		local_irq_restore(flags);

	}

}
@@ -274,7 +277,7 @@ void local_flush_tlb_one(unsigned long page) 
	}

	write_c0_entryhi(oldpid);

	htw_start();

	flush_itlb();

	flush_micro_tlb();

	local_irq_restore(flags);

}
@@ -357,7 +360,7 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) 
	}

	tlbw_use_hazard();

	htw_start();

	flush_itlb_vm(vma);

	flush_micro_tlb_vm(vma);

	local_irq_restore(flags);

}

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