iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

Browse Source 
Pull arm fixes from Russell King:
 "A number of fixes for the PJ4/iwmmxt changes which arm-soc forced me
  to take during the merge window.  This stuff should have been better
  tested and sorted out *before* the merge window"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8042/1: iwmmxt: allow to build iWMMXt on Marvell PJ4B
  ARM: 8041/1: pj4: fix cpu_is_pj4 check
  ARM: 8040/1: pj4: properly detect existence of iWMMXt coprocessor
  ARM: 8039/1: pj4: enable iWMMXt only if CONFIG_IWMMXT is set
  ARM: 8038/1: iwmmxt: explicitly check for supported architectures
This commit is contained in:
Linus Torvalds 2014-04-27 12:55:04 -07:00
commit 2b9d1c050d
5 changed files with 56 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/arm/Kconfig
View File

@ -1111,9 +1111,9 @@ config ARM_NR_BANKS
default 8
config IWMMXT
bool "Enable iWMMXt support" if !CPU_PJ4
depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4
default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4
bool "Enable iWMMXt support"
depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
help
Enable support for iWMMXt context switching at run time if
running on a CPU that supports it.

14
arch/arm/include/asm/cputype.h
View File

@ -222,22 +222,22 @@ static inline int cpu_is_xsc3(void)
#endif
/*
* Marvell's PJ4 core is based on V7 version. It has some modification
* for coprocessor setting. For this reason, we need a way to distinguish
* it.
* Marvell's PJ4 and PJ4B cores are based on V7 version,
* but require a specical sequence for enabling coprocessors.
* For this reason, we need a way to distinguish them.
*/
#ifndef CONFIG_CPU_PJ4
#define cpu_is_pj4() 0
#else
#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B)
static inline int cpu_is_pj4(void)
{
unsigned int id;
id = read_cpuid_id();
if ((id & 0xfffffff0) == 0x562f5840)
if ((id & 0xff0fff00) == 0x560f5800)
return 1;
return 0;
}
#else
#define cpu_is_pj4() 0
#endif
#endif

1
arch/arm/kernel/Makefile
View File

@ -79,6 +79,7 @@ obj-$(CONFIG_CPU_XSCALE) += xscale-cp0.o
obj-$(CONFIG_CPU_XSC3) += xscale-cp0.o
obj-$(CONFIG_CPU_MOHAWK) += xscale-cp0.o
obj-$(CONFIG_CPU_PJ4) += pj4-cp0.o
obj-$(CONFIG_CPU_PJ4B) += pj4-cp0.o
obj-$(CONFIG_IWMMXT) += iwmmxt.o
obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_event_cpu.o

8
arch/arm/kernel/iwmmxt.S
View File

@ -19,12 +19,16 @@
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#if defined(CONFIG_CPU_PJ4)
#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B)
#define PJ4(code...) code
#define XSC(code...)
#else
#elif defined(CONFIG_CPU_MOHAWK) || \
defined(CONFIG_CPU_XSC3) || \
defined(CONFIG_CPU_XSCALE)
#define PJ4(code...)
#define XSC(code...) code
#else
#error "Unsupported iWMMXt architecture"
#endif
#define MMX_WR0 (0x00)

42
arch/arm/kernel/pj4-cp0.c
View File

@ -45,7 +45,7 @@ static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t)
return NOTIFY_DONE;
}
static struct notifier_block iwmmxt_notifier_block = {
static struct notifier_block __maybe_unused iwmmxt_notifier_block = {
.notifier_call = iwmmxt_do,
};
@ -72,6 +72,33 @@ static void __init pj4_cp_access_write(u32 value)
: "=r" (temp) : "r" (value));
}
static int __init pj4_get_iwmmxt_version(void)
{
u32 cp_access, wcid;
cp_access = pj4_cp_access_read();
pj4_cp_access_write(cp_access | 0xf);
/* check if coprocessor 0 and 1 are available */
if ((pj4_cp_access_read() & 0xf) != 0xf) {
pj4_cp_access_write(cp_access);
return -ENODEV;
}
/* read iWMMXt coprocessor id register p1, c0 */
__asm__ __volatile__ ("mrc p1, 0, %0, c0, c0, 0\n" : "=r" (wcid));
pj4_cp_access_write(cp_access);
/* iWMMXt v1 */
if ((wcid & 0xffffff00) == 0x56051000)
return 1;
/* iWMMXt v2 */
if ((wcid & 0xffffff00) == 0x56052000)
return 2;
return -EINVAL;
}
/*
* Disable CP0/CP1 on boot, and let call_fpe() and the iWMMXt lazy
@ -79,17 +106,26 @@ static void __init pj4_cp_access_write(u32 value)
*/
static int __init pj4_cp0_init(void)
{
u32 cp_access;
u32 __maybe_unused cp_access;
int vers;
if (!cpu_is_pj4())
return 0;
vers = pj4_get_iwmmxt_version();
if (vers < 0)
return 0;
#ifndef CONFIG_IWMMXT
pr_info("PJ4 iWMMXt coprocessor detected, but kernel support is missing.\n");
#else
cp_access = pj4_cp_access_read() & ~0xf;
pj4_cp_access_write(cp_access);
printk(KERN_INFO "PJ4 iWMMXt coprocessor enabled.\n");
pr_info("PJ4 iWMMXt v%d coprocessor enabled.\n", vers);
elf_hwcap |= HWCAP_IWMMXT;
thread_register_notifier(&iwmmxt_notifier_block);
#endif
return 0;
}