Re: [PATCH] remove dead cyrix/centaur mtrr init code

Andries Brouwer
2005-03-03T04:42:06Z

On Wed, Mar 02, 2005 at 01:45:43PM +0000, Alan Cox wrote:
> On Mer, 2005-03-02 at 08:02, Dave Jones wrote:
> > If there are any of them still being used out there, I'd be even
> > more surprised if they're running 2.6. Then again, there are
> > probably loonies out there running it on 386/486's. 8-)
>
> I have one here running 2.4 still. I can test a 2.6 fix for the mtrr
> init happily enough.

Good. If I understand things correctly - you or davej or someone will
correct me otherwise - failing to initialise mtrr does not break anything,
it would just mean slower access to certain kinds of memory for certain
kinds of access patterns. (Would you test using an X benchmark?)

Below roughly speaking the same patch as before, but with calls
to the cyrix and centaur mtrr init routines inserted.

Andries

-----

diff -uprN -X /linux/dontdiff a/arch/i386/kernel/cpu/mtrr/centaur.c b/arch/i386/kernel/cpu/mtrr/centaur.c
--- a/arch/i386/kernel/cpu/mtrr/centaur.c 2003-12-18 03:58:38.000000000 +0100
+++ b/arch/i386/kernel/cpu/mtrr/centaur.c 2005-03-02 23:22:10.000000000 +0100
@@ -86,6 +86,7 @@ static void centaur_set_mcr(unsigned int
centaur_mcr[reg].low = low;
wrmsr(MSR_IDT_MCR0 + reg, low, high);
}
+
/*
* Initialise the later (saner) Winchip MCR variant. In this version
* the BIOS can pass us the registers it has used (but not their values)
@@ -168,7 +169,7 @@ centaur_mcr0_init(void)
* Initialise Winchip series MCR registers
*/

-static void __init
+void __init
centaur_mcr_init(void)
{
struct set_mtrr_context ctxt;
@@ -203,7 +204,6 @@ static int centaur_validate_add_page(uns

static struct mtrr_ops centaur_mtrr_ops = {
.vendor = X86_VENDOR_CENTAUR,
- .init = centaur_mcr_init,
.set = centaur_set_mcr,
.get = centaur_get_mcr,
.get_free_region = centaur_get_free_region,
diff -uprN -X /linux/dontdiff a/arch/i386/kernel/cpu/mtrr/cyrix.c b/arch/i386/kernel/cpu/mtrr/cyrix.c
--- a/arch/i386/kernel/cpu/mtrr/cyrix.c 2003-12-18 03:58:56.000000000 +0100
+++ b/arch/i386/kernel/cpu/mtrr/cyrix.c 2005-03-02 23:22:40.000000000 +0100
@@ -218,12 +218,12 @@ typedef struct {
mtrr_type type;
} arr_state_t;

-arr_state_t arr_state[8] __initdata = {
+static arr_state_t arr_state[8] __initdata = {
{0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL},
{0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}
};

-unsigned char ccr_state[7] __initdata = { 0, 0, 0, 0, 0, 0, 0 };
+static unsigned char ccr_state[7] __initdata = { 0, 0, 0, 0, 0, 0, 0 };

static void cyrix_set_all(void)
{
@@ -257,7 +257,7 @@ static void cyrix_set_all(void)
* - (maybe) disable ARR3
* Just to be sure, we enable ARR usage by the processor (CCR5 bit 5 set)
*/
-static void __init
+void __init
cyrix_arr_init(void)
{
struct set_mtrr_context ctxt;
@@ -344,7 +344,6 @@ cyrix_arr_init(void)

static struct mtrr_ops cyrix_mtrr_ops = {
.vendor = X86_VENDOR_CYRIX,
- .init = cyrix_arr_init,
.set_all = cyrix_set_all,
.set = cyrix_set_arr,
.get = cyrix_get_arr,
diff -uprN -X /linux/dontdiff a/arch/i386/kernel/cpu/mtrr/generic.c b/arch/i386/kernel/cpu/mtrr/generic.c
--- a/arch/i386/kernel/cpu/mtrr/generic.c 2005-03-02 20:54:48.000000000 +0100
+++ b/arch/i386/kernel/cpu/mtrr/generic.c 2005-03-02 20:56:19.000000000 +0100
@@ -19,8 +19,7 @@ struct mtrr_state {
};

static unsigned long smp_changes_mask;
-struct mtrr_state mtrr_state = {};
-
+static struct mtrr_state mtrr_state = {};

/* Get the MSR pair relating to a var range */
static void __init
@@ -383,7 +382,7 @@ int generic_validate_add_page(unsigned l
}

-int generic_have_wrcomb(void)
+static int generic_have_wrcomb(void)
{
unsigned long config, dummy;
rdmsr(MTRRcap_MSR, config, dummy);
diff -uprN -X /linux/dontdiff a/arch/i386/kernel/cpu/mtrr/main.c b/arch/i386/kernel/cpu/mtrr/main.c
--- a/arch/i386/kernel/cpu/mtrr/main.c 2004-12-29 03:39:42.000000000 +0100
+++ b/arch/i386/kernel/cpu/mtrr/main.c 2005-03-02 23:21:46.000000000 +0100
@@ -57,10 +57,6 @@ static struct mtrr_ops * mtrr_ops[X86_VE

struct mtrr_ops * mtrr_if = NULL;

-__initdata char *mtrr_if_name[] = {
- "none", "Intel", "AMD K6", "Cyrix ARR", "Centaur MCR"
-};
-
static void set_mtrr(unsigned int reg, unsigned long base,
unsigned long size, mtrr_type type);

@@ -100,7 +96,7 @@ static int have_wrcomb(void)
}

/* This function returns the number of variable MTRRs */
-void __init set_num_var_ranges(void)
+static void __init set_num_var_ranges(void)
{
unsigned long config = 0, dummy;

@@ -526,6 +522,8 @@ EXPORT_SYMBOL(mtrr_del);
* These should be called implicitly, but we can't yet until all the initcall
* stuff is done...
*/
+extern void centaur_mcr_init(void);
+extern void cyrix_arr_init(void);
extern void amd_init_mtrr(void);
extern void cyrix_init_mtrr(void);
extern void centaur_init_mtrr(void);
@@ -665,6 +663,7 @@ static int __init mtrr_init(void)
break;
case X86_VENDOR_CENTAUR:
if (cpu_has_centaur_mcr) {
+ centaur_mcr_init();
mtrr_if = mtrr_ops[X86_VENDOR_CENTAUR];
size_or_mask = 0xfff00000; /* 32 bits */
size_and_mask = 0;
@@ -672,6 +671,7 @@ static int __init mtrr_init(void)
break;
case X86_VENDOR_CYRIX:
if (cpu_has_cyrix_arr) {
+ cyrix_arr_init();
mtrr_if = mtrr_ops[X86_VENDOR_CYRIX];
size_or_mask = 0xfff00000; /* 32 bits */
size_and_mask = 0;
diff -uprN -X /linux/dontdiff a/arch/i386/kernel/cpu/mtrr/mtrr.h b/arch/i386/kernel/cpu/mtrr/mtrr.h
--- a/arch/i386/kernel/cpu/mtrr/mtrr.h 2004-10-30 21:43:59.000000000 +0200
+++ b/arch/i386/kernel/cpu/mtrr/mtrr.h 2005-03-02 23:17:52.000000000 +0100
@@ -37,7 +37,6 @@ typedef u8 mtrr_type;
struct mtrr_ops {
u32 vendor;
u32 use_intel_if;
- void (*init)(void);
void (*set)(unsigned int reg, unsigned long base,
unsigned long size, mtrr_type type);
void (*set_all)(void);
@@ -57,7 +56,6 @@ extern int generic_validate_add_page(uns

extern struct mtrr_ops generic_mtrr_ops;

-extern int generic_have_wrcomb(void);
extern int positive_have_wrcomb(void);

/* library functions for processor-specific routines */
@@ -96,4 +94,3 @@ void finalize_mtrr_state(void);
void mtrr_state_warn(void);
char *mtrr_attrib_to_str(int x);

-extern char * mtrr_if_name[];