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[ARM] Remove cache type printks
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The cache type register found in ARMv5 and later CPUs changes format
and meaning depending on the CPU architecture version.  Currently,
this code:
a) doesn't work for everything - Xscale's are identified as
   'unknown 5'.
b) is not able to tell whether the caches are VIVT or VIPT from the
   cache type.
c) prints rubbish on some ARMv6 and ARMv7+ CPUs.

The two solutions to this are:
1. Add yet more code to decode and print the various different register
   formats.
2. Remove the code altogther.

The code only exists to decode and print the cache parameters.
Increasing the complexity of it just for the sake of a few prinks
isn't worth it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored and Russell King committed Sep 25, 2008
1 parent 1562f98 commit 90f1e08
Showing 1 changed file with 1 addition and 141 deletions.
142 changes: 1 addition & 141 deletions arch/arm/kernel/setup.c
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Original file line number Diff line number Diff line change
Expand Up @@ -176,63 +176,6 @@ static struct resource io_res[] = {
#define lp1 io_res[1]
#define lp2 io_res[2]

static const char *cache_types[16] = {
"write-through",
"write-back",
"write-back",
"undefined 3",
"undefined 4",
"undefined 5",
"write-back",
"write-back",
"undefined 8",
"undefined 9",
"undefined 10",
"undefined 11",
"undefined 12",
"undefined 13",
"write-back",
"undefined 15",
};

static const char *cache_clean[16] = {
"not required",
"read-block",
"cp15 c7 ops",
"undefined 3",
"undefined 4",
"undefined 5",
"cp15 c7 ops",
"cp15 c7 ops",
"undefined 8",
"undefined 9",
"undefined 10",
"undefined 11",
"undefined 12",
"undefined 13",
"cp15 c7 ops",
"undefined 15",
};

static const char *cache_lockdown[16] = {
"not supported",
"not supported",
"not supported",
"undefined 3",
"undefined 4",
"undefined 5",
"format A",
"format B",
"undefined 8",
"undefined 9",
"undefined 10",
"undefined 11",
"undefined 12",
"undefined 13",
"format C",
"undefined 15",
};

static const char *proc_arch[] = {
"undefined/unknown",
"3",
Expand All @@ -253,48 +196,6 @@ static const char *proc_arch[] = {
"?(17)",
};

#define CACHE_TYPE(x) (((x) >> 25) & 15)
#define CACHE_S(x) ((x) & (1 << 24))
#define CACHE_DSIZE(x) (((x) >> 12) & 4095) /* only if S=1 */
#define CACHE_ISIZE(x) ((x) & 4095)

#define CACHE_SIZE(y) (((y) >> 6) & 7)
#define CACHE_ASSOC(y) (((y) >> 3) & 7)
#define CACHE_M(y) ((y) & (1 << 2))
#define CACHE_LINE(y) ((y) & 3)

static inline void dump_cache(const char *prefix, int cpu, unsigned int cache)
{
unsigned int mult = 2 + (CACHE_M(cache) ? 1 : 0);

printk("CPU%u: %s: %d bytes, associativity %d, %d byte lines, %d sets\n",
cpu, prefix,
mult << (8 + CACHE_SIZE(cache)),
(mult << CACHE_ASSOC(cache)) >> 1,
8 << CACHE_LINE(cache),
1 << (6 + CACHE_SIZE(cache) - CACHE_ASSOC(cache) -
CACHE_LINE(cache)));
}

static void __init dump_cpu_info(int cpu)
{
unsigned int info = read_cpuid_cachetype();

if (info != read_cpuid_id()) {
printk("CPU%u: D %s %s cache\n", cpu, cache_is_vivt() ? "VIVT" : "VIPT",
cache_types[CACHE_TYPE(info)]);
if (CACHE_S(info)) {
dump_cache("I cache", cpu, CACHE_ISIZE(info));
dump_cache("D cache", cpu, CACHE_DSIZE(info));
} else {
dump_cache("cache", cpu, CACHE_ISIZE(info));
}
}

if (arch_is_coherent())
printk("Cache coherency enabled\n");
}

int cpu_architecture(void)
{
int cpu_arch;
Expand Down Expand Up @@ -383,8 +284,7 @@ static void __init setup_processor(void)
/*
* cpu_init - initialise one CPU.
*
* cpu_init dumps the cache information, initialises SMP specific
* information, and sets up the per-CPU stacks.
* cpu_init sets up the per-CPU stacks.
*/
void cpu_init(void)
{
Expand All @@ -396,9 +296,6 @@ void cpu_init(void)
BUG();
}

if (system_state == SYSTEM_BOOTING)
dump_cpu_info(cpu);

/*
* setup stacks for re-entrant exception handlers
*/
Expand Down Expand Up @@ -865,22 +762,6 @@ static const char *hwcap_str[] = {
NULL
};

static void
c_show_cache(struct seq_file *m, const char *type, unsigned int cache)
{
unsigned int mult = 2 + (CACHE_M(cache) ? 1 : 0);

seq_printf(m, "%s size\t\t: %d\n"
"%s assoc\t\t: %d\n"
"%s line length\t: %d\n"
"%s sets\t\t: %d\n",
type, mult << (8 + CACHE_SIZE(cache)),
type, (mult << CACHE_ASSOC(cache)) >> 1,
type, 8 << CACHE_LINE(cache),
type, 1 << (6 + CACHE_SIZE(cache) - CACHE_ASSOC(cache) -
CACHE_LINE(cache)));
}

static int c_show(struct seq_file *m, void *v)
{
int i;
Expand Down Expand Up @@ -934,27 +815,6 @@ static int c_show(struct seq_file *m, void *v)
}
seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);

{
unsigned int cache_info = read_cpuid_cachetype();
if (cache_info != read_cpuid_id()) {
seq_printf(m, "Cache type\t: %s\n"
"Cache clean\t: %s\n"
"Cache lockdown\t: %s\n"
"Cache format\t: %s\n",
cache_types[CACHE_TYPE(cache_info)],
cache_clean[CACHE_TYPE(cache_info)],
cache_lockdown[CACHE_TYPE(cache_info)],
CACHE_S(cache_info) ? "Harvard" : "Unified");

if (CACHE_S(cache_info)) {
c_show_cache(m, "I", CACHE_ISIZE(cache_info));
c_show_cache(m, "D", CACHE_DSIZE(cache_info));
} else {
c_show_cache(m, "Cache", CACHE_ISIZE(cache_info));
}
}
}

seq_puts(m, "\n");

seq_printf(m, "Hardware\t: %s\n", machine_name);
Expand Down

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