Commit 6e4662ff authored by Stuart Menefy's avatar Stuart Menefy Committed by Paul Mundt
Browse files

sh: Use MMU.TTB register as pointer to current pgd.



Add TTB accessor functions and give it a sensible default
value. We will use this later for optimizing the fault
path.
Signed-off-by: default avatarStuart Menefy <stuart.menefy@st.com>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent b5a1bcbe
......@@ -155,9 +155,6 @@ extern char __init_begin, __init_end;
/*
* paging_init() sets up the page tables
*
* This routines also unmaps the page at virtual kernel address 0, so
* that we can trap those pesky NULL-reference errors in the kernel.
*/
void __init paging_init(void)
{
......@@ -180,14 +177,11 @@ void __init paging_init(void)
*/
{
unsigned long max_dma, low, start_pfn;
pgd_t *pg_dir;
int i;
/* We don't need kernel mapping as hardware support that. */
pg_dir = swapper_pg_dir;
for (i = 0; i < PTRS_PER_PGD; i++)
pgd_val(pg_dir[i]) = 0;
/* We don't need to map the kernel through the TLB, as
* it is permanatly mapped using P1. So clear the
* entire pgd. */
memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
/* Turn on the MMU */
enable_mmu();
......@@ -206,6 +200,10 @@ void __init paging_init(void)
}
}
/* Set an initial value for the MMU.TTB so we don't have to
* check for a null value. */
set_TTB(swapper_pg_dir);
#elif defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH4)
/*
* If we don't have CONFIG_MMU set and the processor in question
......
......@@ -10,7 +10,6 @@
#include <asm/cpu/mmu_context.h>
#include <asm/tlbflush.h>
#include <asm/pgalloc.h>
#include <asm/uaccess.h>
#include <asm/io.h>
......@@ -42,10 +41,8 @@ extern unsigned long mmu_context_cache;
/*
* Get MMU context if needed.
*/
static __inline__ void
get_mmu_context(struct mm_struct *mm)
static inline void get_mmu_context(struct mm_struct *mm)
{
extern void flush_tlb_all(void);
unsigned long mc = mmu_context_cache;
/* Check if we have old version of context. */
......@@ -61,6 +58,7 @@ get_mmu_context(struct mm_struct *mm)
* Flush all TLB and start new cycle.
*/
flush_tlb_all();
/*
* Fix version; Note that we avoid version #0
* to distingush NO_CONTEXT.
......@@ -75,11 +73,10 @@ get_mmu_context(struct mm_struct *mm)
* Initialize the context related info for a new mm_struct
* instance.
*/
static __inline__ int init_new_context(struct task_struct *tsk,
static inline int init_new_context(struct task_struct *tsk,
struct mm_struct *mm)
{
mm->context.id = NO_CONTEXT;
return 0;
}
......@@ -87,12 +84,12 @@ static __inline__ int init_new_context(struct task_struct *tsk,
* Destroy context related info for an mm_struct that is about
* to be put to rest.
*/
static __inline__ void destroy_context(struct mm_struct *mm)
static inline void destroy_context(struct mm_struct *mm)
{
/* Do nothing */
}
static __inline__ void set_asid(unsigned long asid)
static inline void set_asid(unsigned long asid)
{
unsigned long __dummy;
......@@ -105,7 +102,7 @@ static __inline__ void set_asid(unsigned long asid)
"r" (0xffffff00));
}
static __inline__ unsigned long get_asid(void)
static inline unsigned long get_asid(void)
{
unsigned long asid;
......@@ -120,24 +117,29 @@ static __inline__ unsigned long get_asid(void)
* After we have set current->mm to a new value, this activates
* the context for the new mm so we see the new mappings.
*/
static __inline__ void activate_context(struct mm_struct *mm)
static inline void activate_context(struct mm_struct *mm)
{
get_mmu_context(mm);
set_asid(mm->context.id & MMU_CONTEXT_ASID_MASK);
}
/* MMU_TTB can be used for optimizing the fault handling.
(Currently not used) */
static __inline__ void switch_mm(struct mm_struct *prev,
struct mm_struct *next,
struct task_struct *tsk)
/* MMU_TTB is used for optimizing the fault handling. */
static inline void set_TTB(pgd_t *pgd)
{
if (likely(prev != next)) {
unsigned long __pgdir = (unsigned long)next->pgd;
ctrl_outl((unsigned long)pgd, MMU_TTB);
}
__asm__ __volatile__("mov.l %0, %1"
: /* no output */
: "r" (__pgdir), "m" (__m(MMU_TTB)));
static inline pgd_t *get_TTB(void)
{
return (pgd_t *)ctrl_inl(MMU_TTB);
}
static inline void switch_mm(struct mm_struct *prev,
struct mm_struct *next,
struct task_struct *tsk)
{
if (likely(prev != next)) {
set_TTB(next->pgd);
activate_context(next);
}
}
......@@ -147,7 +149,7 @@ static __inline__ void switch_mm(struct mm_struct *prev,
#define activate_mm(prev, next) \
switch_mm((prev),(next),NULL)
static __inline__ void
static inline void
enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment