Commit 5d61a217 authored by Scott Wood's avatar Scott Wood Committed by Benjamin Herrenschmidt
Browse files

powerpc/nohash: Split __early_init_mmu() into boot and secondary 



__early_init_mmu() does some things that are really only needed by the
boot cpu.  On FSL booke, This includes calling
memblock_enforce_memory_limit(), which is labelled __init.  Secondary
cpu init code can't be __init as that would break CPU hotplug.

While it's probably a bug that memblock_enforce_memory_limit() isn't
__init_memblock instead, there's no reason why we should be doing this
stuff for secondary cpus in the first place.

Signed-off-by: default avatarScott Wood <scottwood@freescale.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 58d08e3b

arch/powerpc/mm/tlb_nohash.c

+66 −45
Original line number Diff line number Diff line
@@ -581,42 +581,10 @@ static void setup_mmu_htw(void) 
/*

 * Early initialization of the MMU TLB code

 */

static void __early_init_mmu(int boot_cpu)

static void early_init_this_mmu(void)

{

	unsigned int mas4;



	/* XXX This will have to be decided at runtime, but right

	 * now our boot and TLB miss code hard wires it. Ideally

	 * we should find out a suitable page size and patch the

	 * TLB miss code (either that or use the PACA to store

	 * the value we want)

	 */

	mmu_linear_psize = MMU_PAGE_1G;



	/* XXX This should be decided at runtime based on supported

	 * page sizes in the TLB, but for now let's assume 16M is

	 * always there and a good fit (which it probably is)

	 *

	 * Freescale booke only supports 4K pages in TLB0, so use that.

	 */

	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))

		mmu_vmemmap_psize = MMU_PAGE_4K;

	else

		mmu_vmemmap_psize = MMU_PAGE_16M;



	/* XXX This code only checks for TLB 0 capabilities and doesn't

	 *     check what page size combos are supported by the HW. It

	 *     also doesn't handle the case where a separate array holds

	 *     the IND entries from the array loaded by the PT.

	 */

	if (boot_cpu) {

		/* Look for supported page sizes */

		setup_page_sizes();



		/* Look for HW tablewalk support */

		setup_mmu_htw();

	}



	/* Set MAS4 based on page table setting */



	mas4 = 0x4 << MAS4_WIMGED_SHIFT;
@@ -650,11 +618,6 @@ static void __early_init_mmu(int boot_cpu) 
	}

	mtspr(SPRN_MAS4, mas4);



	/* Set the global containing the top of the linear mapping

	 * for use by the TLB miss code

	 */

	linear_map_top = memblock_end_of_DRAM();



#ifdef CONFIG_PPC_FSL_BOOK3E

	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {

		unsigned int num_cams;
@@ -662,10 +625,49 @@ static void __early_init_mmu(int boot_cpu) 
		/* use a quarter of the TLBCAM for bolted linear map */

		num_cams = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) / 4;

		linear_map_top = map_mem_in_cams(linear_map_top, num_cams);

	}

#endif



		/* limit memory so we dont have linear faults */

		memblock_enforce_memory_limit(linear_map_top);

	/* A sync won't hurt us after mucking around with

	 * the MMU configuration

	 */

	mb();

}



static void __init early_init_mmu_global(void)

{

	/* XXX This will have to be decided at runtime, but right

	 * now our boot and TLB miss code hard wires it. Ideally

	 * we should find out a suitable page size and patch the

	 * TLB miss code (either that or use the PACA to store

	 * the value we want)

	 */

	mmu_linear_psize = MMU_PAGE_1G;



	/* XXX This should be decided at runtime based on supported

	 * page sizes in the TLB, but for now let's assume 16M is

	 * always there and a good fit (which it probably is)

	 *

	 * Freescale booke only supports 4K pages in TLB0, so use that.

	 */

	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))

		mmu_vmemmap_psize = MMU_PAGE_4K;

	else

		mmu_vmemmap_psize = MMU_PAGE_16M;



	/* XXX This code only checks for TLB 0 capabilities and doesn't

	 *     check what page size combos are supported by the HW. It

	 *     also doesn't handle the case where a separate array holds

	 *     the IND entries from the array loaded by the PT.

	 */

	/* Look for supported page sizes */

	setup_page_sizes();



	/* Look for HW tablewalk support */

	setup_mmu_htw();



#ifdef CONFIG_PPC_FSL_BOOK3E

	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {

		if (book3e_htw_mode == PPC_HTW_NONE) {

			extlb_level_exc = EX_TLB_SIZE;

			patch_exception(0x1c0, exc_data_tlb_miss_bolted_book3e);
@@ -675,22 +677,41 @@ static void __early_init_mmu(int boot_cpu) 
	}

#endif



	/* A sync won't hurt us after mucking around with

	 * the MMU configuration

	/* Set the global containing the top of the linear mapping

	 * for use by the TLB miss code

	 */

	mb();

	linear_map_top = memblock_end_of_DRAM();

}



static void __init early_mmu_set_memory_limit(void)

{

#ifdef CONFIG_PPC_FSL_BOOK3E

	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E)) {

		/*

		 * Limit memory so we dont have linear faults.

		 * Unlike memblock_set_current_limit, which limits

		 * memory available during early boot, this permanently

		 * reduces the memory available to Linux.  We need to

		 * do this because highmem is not supported on 64-bit.

		 */

		memblock_enforce_memory_limit(linear_map_top);

	}

#endif



	memblock_set_current_limit(linear_map_top);

}



/* boot cpu only */

void __init early_init_mmu(void)

{

	__early_init_mmu(1);

	early_init_mmu_global();

	early_init_this_mmu();

	early_mmu_set_memory_limit();

}



void early_init_mmu_secondary(void)

{

	__early_init_mmu(0);

	early_init_this_mmu();

}



void setup_initial_memory_limit(phys_addr_t first_memblock_base,

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