[PATCH v2 12/16] powerpc/64e: remove mmu_linear_psize

Nicholas Piggin npiggin at gmail.com
Thu Oct 21 14:54:13 AEDT 2021


mmu_linear_psize is only set at boot once on 64e, is not necessarily
the correct size of the linear map pages, and is never used anywhere
except memremap_compat_align.

Remove mmu_linear_psize and hard code the 1GB value instead in
memremap_compat_align.

Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
 arch/powerpc/mm/ioremap.c    | 6 +++++-
 arch/powerpc/mm/nohash/tlb.c | 9 ---------
 2 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/mm/ioremap.c b/arch/powerpc/mm/ioremap.c
index 57342154d2b0..730c3bbe4759 100644
--- a/arch/powerpc/mm/ioremap.c
+++ b/arch/powerpc/mm/ioremap.c
@@ -109,12 +109,16 @@ void __iomem *do_ioremap(phys_addr_t pa, phys_addr_t offset, unsigned long size,
 */
 unsigned long memremap_compat_align(void)
 {
+#ifdef CONFIG_PPC_BOOK3E_64
+	// 1GB maximum possible size of the linear mapping.
+	return max(SUBSECTION_SIZE, 1UL << 30);
+#else
 	unsigned int shift = mmu_psize_defs[mmu_linear_psize].shift;
 
 	if (radix_enabled())
 		return SUBSECTION_SIZE;
 	return max(SUBSECTION_SIZE, 1UL << shift);
-
+#endif
 }
 EXPORT_SYMBOL_GPL(memremap_compat_align);
 #endif
diff --git a/arch/powerpc/mm/nohash/tlb.c b/arch/powerpc/mm/nohash/tlb.c
index 5872f69141d5..8c1523ae7f7f 100644
--- a/arch/powerpc/mm/nohash/tlb.c
+++ b/arch/powerpc/mm/nohash/tlb.c
@@ -150,7 +150,6 @@ static inline int mmu_get_tsize(int psize)
  */
 #ifdef CONFIG_PPC64
 
-int mmu_linear_psize;		/* Page size used for the linear mapping */
 int mmu_pte_psize;		/* Page size used for PTE pages */
 int mmu_vmemmap_psize;		/* Page size used for the virtual mem map */
 int book3e_htw_mode;		/* HW tablewalk?  Value is PPC_HTW_* */
@@ -655,14 +654,6 @@ static void early_init_this_mmu(void)
 
 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)
-- 
2.23.0



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