ARM: kernel: update cpuinfo to print all online CPUs features

Currently, reading /proc/cpuinfo provides userspace with CPU ID of
the CPU carrying out the read from the file. This is fine as long as all
CPUs in the system are the same. With the advent of big.LITTLE and
heterogenous ARM systems this approach provides user space with incorrect
bits of information since CPU ids in the system might differ from the one
provided by the CPU reading the file.

This patch updates the cpuinfo show function so that a read from
/proc/cpuinfo prints HW information for all online CPUs at once, mirroring
 x86 behaviour.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
This commit is contained in:
Lorenzo Pieralisi 2012-09-10 18:55:21 +01:00
parent e8d432c9cf
commit b4b8f770eb
1 changed files with 35 additions and 35 deletions

View File

@ -841,12 +841,9 @@ static const char *hwcap_str[] = {
static int c_show(struct seq_file *m, void *v)
{
int i;
int i, j;
u32 cpuid;
seq_printf(m, "Processor\t: %s rev %d (%s)\n",
cpu_name, read_cpuid_id() & 15, elf_platform);
#if defined(CONFIG_SMP)
for_each_online_cpu(i) {
/*
* glibc reads /proc/cpuinfo to determine the number of
@ -854,45 +851,48 @@ static int c_show(struct seq_file *m, void *v)
* "processor". Give glibc what it expects.
*/
seq_printf(m, "processor\t: %d\n", i);
seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
cpuid = is_smp() ? per_cpu(cpu_data, i).cpuid : read_cpuid_id();
seq_printf(m, "model name\t: %s rev %d (%s)\n",
cpu_name, cpuid & 15, elf_platform);
#if defined(CONFIG_SMP)
seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
(per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
}
#else /* CONFIG_SMP */
seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
loops_per_jiffy / (500000/HZ),
(loops_per_jiffy / (5000/HZ)) % 100);
#else
seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
loops_per_jiffy / (500000/HZ),
(loops_per_jiffy / (5000/HZ)) % 100);
#endif
/* dump out the processor features */
seq_puts(m, "Features\t: ");
/* dump out the processor features */
seq_puts(m, "Features\t: ");
for (j = 0; hwcap_str[j]; j++)
if (elf_hwcap & (1 << j))
seq_printf(m, "%s ", hwcap_str[j]);
for (i = 0; hwcap_str[i]; i++)
if (elf_hwcap & (1 << i))
seq_printf(m, "%s ", hwcap_str[i]);
seq_printf(m, "\nCPU implementer\t: 0x%02x\n", cpuid >> 24);
seq_printf(m, "CPU architecture: %s\n",
proc_arch[cpu_architecture()]);
seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
seq_printf(m, "CPU architecture: %s\n", proc_arch[cpu_architecture()]);
if ((read_cpuid_id() & 0x0008f000) == 0x00000000) {
/* pre-ARM7 */
seq_printf(m, "CPU part\t: %07x\n", read_cpuid_id() >> 4);
} else {
if ((read_cpuid_id() & 0x0008f000) == 0x00007000) {
/* ARM7 */
seq_printf(m, "CPU variant\t: 0x%02x\n",
(read_cpuid_id() >> 16) & 127);
if ((cpuid & 0x0008f000) == 0x00000000) {
/* pre-ARM7 */
seq_printf(m, "CPU part\t: %07x\n", cpuid >> 4);
} else {
/* post-ARM7 */
seq_printf(m, "CPU variant\t: 0x%x\n",
(read_cpuid_id() >> 20) & 15);
if ((cpuid & 0x0008f000) == 0x00007000) {
/* ARM7 */
seq_printf(m, "CPU variant\t: 0x%02x\n",
(cpuid >> 16) & 127);
} else {
/* post-ARM7 */
seq_printf(m, "CPU variant\t: 0x%x\n",
(cpuid >> 20) & 15);
}
seq_printf(m, "CPU part\t: 0x%03x\n",
(cpuid >> 4) & 0xfff);
}
seq_printf(m, "CPU part\t: 0x%03x\n",
(read_cpuid_id() >> 4) & 0xfff);
seq_printf(m, "CPU revision\t: %d\n\n", cpuid & 15);
}
seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);
seq_puts(m, "\n");
seq_printf(m, "Hardware\t: %s\n", machine_name);
seq_printf(m, "Revision\t: %04x\n", system_rev);