[PATCH 09/12] MIPS: mm: Pass scratch register through to iPTE_SW

From: Paul Burton
Date: Fri Apr 15 2016 - 06:39:43 EST


Rather than hardcode a scratch register for the XPA case in iPTE_SW,
pass one through from the work registers allocated by the caller. This
allows for the XPA path to function correctly regardless of the work
registers in use.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---

arch/mips/mm/tlbex.c | 24 +++++++++++-------------
1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 004cd9f..d7a7b3d 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -1526,14 +1526,12 @@ iPTE_LW(u32 **p, unsigned int pte, unsigned int ptr)

static void
iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
- unsigned int mode)
+ unsigned int mode, unsigned int scratch)
{
#ifdef CONFIG_PHYS_ADDR_T_64BIT
unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);

if (config_enabled(CONFIG_XPA) && !cpu_has_64bits) {
- const int scratch = 1; /* Our extra working register */
-
uasm_i_lui(p, scratch, (mode >> 16));
uasm_i_or(p, pte, pte, scratch);
} else
@@ -1630,11 +1628,11 @@ build_pte_present(u32 **p, struct uasm_reloc **r,
/* Make PTE valid, store result in PTR. */
static void
build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
- unsigned int ptr)
+ unsigned int ptr, unsigned int scratch)
{
unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;

- iPTE_SW(p, r, pte, ptr, mode);
+ iPTE_SW(p, r, pte, ptr, mode, scratch);
}

/*
@@ -1670,12 +1668,12 @@ build_pte_writable(u32 **p, struct uasm_reloc **r,
*/
static void
build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
- unsigned int ptr)
+ unsigned int ptr, unsigned int scratch)
{
unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
| _PAGE_DIRTY);

- iPTE_SW(p, r, pte, ptr, mode);
+ iPTE_SW(p, r, pte, ptr, mode, scratch);
}

/*
@@ -1780,7 +1778,7 @@ static void build_r3000_tlb_load_handler(void)
build_r3000_tlbchange_handler_head(&p, K0, K1);
build_pte_present(&p, &r, K0, K1, -1, label_nopage_tlbl);
uasm_i_nop(&p); /* load delay */
- build_make_valid(&p, &r, K0, K1);
+ build_make_valid(&p, &r, K0, K1, -1);
build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);

uasm_l_nopage_tlbl(&l, p);
@@ -1811,7 +1809,7 @@ static void build_r3000_tlb_store_handler(void)
build_r3000_tlbchange_handler_head(&p, K0, K1);
build_pte_writable(&p, &r, K0, K1, -1, label_nopage_tlbs);
uasm_i_nop(&p); /* load delay */
- build_make_write(&p, &r, K0, K1);
+ build_make_write(&p, &r, K0, K1, -1);
build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);

uasm_l_nopage_tlbs(&l, p);
@@ -1842,7 +1840,7 @@ static void build_r3000_tlb_modify_handler(void)
build_r3000_tlbchange_handler_head(&p, K0, K1);
build_pte_modifiable(&p, &r, K0, K1, -1, label_nopage_tlbm);
uasm_i_nop(&p); /* load delay */
- build_make_write(&p, &r, K0, K1);
+ build_make_write(&p, &r, K0, K1, -1);
build_r3000_pte_reload_tlbwi(&p, K0, K1);

uasm_l_nopage_tlbm(&l, p);
@@ -2010,7 +2008,7 @@ static void build_r4000_tlb_load_handler(void)
}
uasm_l_tlbl_goaround1(&l, p);
}
- build_make_valid(&p, &r, wr.r1, wr.r2);
+ build_make_valid(&p, &r, wr.r1, wr.r2, wr.r3);
build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);

#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
@@ -2124,7 +2122,7 @@ static void build_r4000_tlb_store_handler(void)
build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
if (m4kc_tlbp_war())
build_tlb_probe_entry(&p);
- build_make_write(&p, &r, wr.r1, wr.r2);
+ build_make_write(&p, &r, wr.r1, wr.r2, wr.r3);
build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);

#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
@@ -2180,7 +2178,7 @@ static void build_r4000_tlb_modify_handler(void)
if (m4kc_tlbp_war())
build_tlb_probe_entry(&p);
/* Present and writable bits set, set accessed and dirty bits. */
- build_make_write(&p, &r, wr.r1, wr.r2);
+ build_make_write(&p, &r, wr.r1, wr.r2, wr.r3);
build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);

#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
--
2.8.0