powerpc/fsl-booke-64: Don't limit ppc64_rma_size to one TLB entry

This is required for kdump to work when loaded at at an address that
does not fall within the first TLB entry -- which can easily happen
because while the lower limit is enforced via reserved memory, which
doesn't affect how much is mapped, the upper limit is enforced via a
different mechanism that does.  Thus, more TLB entries are needed than
would normally be used, as the total memory to be mapped might not be a
power of two.

Signed-off-by: Scott Wood <scottwood@freescale.com>

1 files changed, 15 insertions, 7 deletions

diff --git a/arch/powerpc/mm/fsl_booke_mmu.c b/arch/powerpc/mm/fsl_booke_mmu.c
index bb1f88c10377..f3afe3d97f6b 100644
--- a/arch/powerpc/mm/fsl_booke_mmu.c
+++ b/arch/powerpc/mm/fsl_booke_mmu.c
@@ -169,7 +169,8 @@ unsigned long calc_cam_sz(unsigned long ram, unsigned long virt,
 }
 
 static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
-					unsigned long ram, int max_cam_idx)
+					unsigned long ram, int max_cam_idx,
+					bool dryrun)
 {
 	int i;
 	unsigned long amount_mapped = 0;
@@ -179,7 +180,9 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
 		unsigned long cam_sz;
 
 		cam_sz = calc_cam_sz(ram, virt, phys);
-		settlbcam(i, virt, phys, cam_sz, pgprot_val(PAGE_KERNEL_X), 0);
+		if (!dryrun)
+			settlbcam(i, virt, phys, cam_sz,
+				  pgprot_val(PAGE_KERNEL_X), 0);
 
 		ram -= cam_sz;
 		amount_mapped += cam_sz;
@@ -187,6 +190,9 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
 		phys += cam_sz;
 	}
 
+	if (dryrun)
+		return amount_mapped;
+
 	loadcam_multi(0, i, max_cam_idx);
 	tlbcam_index = i;
 
@@ -199,12 +205,12 @@ static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
 	return amount_mapped;
 }
 
-unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx)
+unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx, bool dryrun)
 {
 	unsigned long virt = PAGE_OFFSET;
 	phys_addr_t phys = memstart_addr;
 
-	return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx);
+	return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx, dryrun);
 }
 
 #ifdef CONFIG_PPC32
@@ -235,7 +241,7 @@ void __init adjust_total_lowmem(void)
 	ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem);
 
 	i = switch_to_as1();
-	__max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM);
+	__max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, false);
 	restore_to_as0(i, 0, 0, 1);
 
 	pr_info("Memory CAM mapping: ");
@@ -303,10 +309,12 @@ notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start)
 		n = switch_to_as1();
 		/* map a 64M area for the second relocation */
 		if (memstart_addr > start)
-			map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM);
+			map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM,
+					false);
 		else
 			map_mem_in_cams_addr(start, PAGE_OFFSET + offset,
-					0x4000000, CONFIG_LOWMEM_CAM_NUM);
+					0x4000000, CONFIG_LOWMEM_CAM_NUM,
+					false);
 		restore_to_as0(n, offset, __va(dt_ptr), 1);
 		/* We should never reach here */
 		panic("Relocation error");