From cab25bc7537badea41f635a049f45408c24dff26 Mon Sep 17 00:00:00 2001
From: Paul Burton <paul.burton@imgtec.com>
Date: Tue, 22 Sep 2015 12:03:37 -0700
Subject: [PATCH] MIPS: Extend hardware table walking support to MIPS64
Extend the existing support for Hardware Table Walking (HTW) to MIPS64
systems by supporting PMDs & setting the pointer size bit in PWSize,
then ceasing to blacklist HTW on MIPS64 systems.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11224/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
arch/mips/kernel/cpu-probe.c | 3 +--
arch/mips/mm/tlbex.c | 8 +++++++-
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 09a51d091941b..6b9064499bd3d 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -536,8 +536,7 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c)
c->options |= MIPS_CPU_SEGMENTS;
if (config3 & MIPS_CONF3_MSA)
c->ases |= MIPS_ASE_MSA;
- /* Only tested on 32-bit cores */
- if ((config3 & MIPS_CONF3_PW) && config_enabled(CONFIG_32BIT)) {
+ if (config3 & MIPS_CONF3_PW) {
c->htw_seq = 0;
c->options |= MIPS_CPU_HTW;
}
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 6b7cc20efd92a..32e0be27673fe 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -2284,6 +2284,10 @@ static void config_htw_params(void)
/* re-initialize the PTI field including the even/odd bit */
pwfield &= ~MIPS_PWFIELD_PTI_MASK;
pwfield |= PAGE_SHIFT << MIPS_PWFIELD_PTI_SHIFT;
+ if (CONFIG_PGTABLE_LEVELS >= 3) {
+ pwfield &= ~MIPS_PWFIELD_MDI_MASK;
+ pwfield |= PMD_SHIFT << MIPS_PWFIELD_MDI_SHIFT;
+ }
/* Set the PTEI right shift */
ptei = _PAGE_GLOBAL_SHIFT << MIPS_PWFIELD_PTEI_SHIFT;
pwfield |= ptei;
@@ -2305,9 +2309,11 @@ static void config_htw_params(void)
pwsize = ilog2(PTRS_PER_PGD) << MIPS_PWSIZE_GDW_SHIFT;
pwsize |= ilog2(PTRS_PER_PTE) << MIPS_PWSIZE_PTW_SHIFT;
+ if (CONFIG_PGTABLE_LEVELS >= 3)
+ pwsize |= ilog2(PTRS_PER_PMD) << MIPS_PWSIZE_MDW_SHIFT;
/* If XPA has been enabled, PTEs are 64-bit in size. */
- if (read_c0_pagegrain() & PG_ELPA)
+ if (config_enabled(CONFIG_64BITS) || (read_c0_pagegrain() & PG_ELPA))
pwsize |= 1;
write_c0_pwsize(pwsize);
--
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