Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
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
+56
-15
+3
-3
arch/arm/Kconfig
+3
-3
arch/arm/Kconfig
···
1111
1111
default 8
1112
1112
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1113
config IWMMXT
1114
-
bool "Enable iWMMXt support" if !CPU_PJ4
1115
-
depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4
1116
-
default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4
1114
+
bool "Enable iWMMXt support"
1115
+
depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
1116
+
default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
1117
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help
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Enable support for iWMMXt context switching at run time if
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1119
running on a CPU that supports it.
+7
-7
arch/arm/include/asm/cputype.h
+7
-7
arch/arm/include/asm/cputype.h
···
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#endif
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/*
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-
* Marvell's PJ4 core is based on V7 version. It has some modification
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-
* for coprocessor setting. For this reason, we need a way to distinguish
227
-
* it.
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+
* Marvell's PJ4 and PJ4B cores are based on V7 version,
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+
* but require a specical sequence for enabling coprocessors.
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+
* For this reason, we need a way to distinguish them.
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*/
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-
#ifndef CONFIG_CPU_PJ4
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-
#define cpu_is_pj4() 0
231
-
#else
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+
#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B)
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static inline int cpu_is_pj4(void)
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{
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unsigned int id;
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id = read_cpuid_id();
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-
if ((id & 0xfffffff0) == 0x562f5840)
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+
if ((id & 0xff0fff00) == 0x560f5800)
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return 1;
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return 0;
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}
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+
#else
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+
#define cpu_is_pj4() 0
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#endif
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#endif
+1
arch/arm/kernel/Makefile
+1
arch/arm/kernel/Makefile
···
79
79
obj-$(CONFIG_CPU_XSC3) += xscale-cp0.o
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obj-$(CONFIG_CPU_MOHAWK) += xscale-cp0.o
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obj-$(CONFIG_CPU_PJ4) += pj4-cp0.o
82
+
obj-$(CONFIG_CPU_PJ4B) += pj4-cp0.o
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obj-$(CONFIG_IWMMXT) += iwmmxt.o
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obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
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obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_event_cpu.o
+6
-2
arch/arm/kernel/iwmmxt.S
+6
-2
arch/arm/kernel/iwmmxt.S
···
19
19
#include <asm/thread_info.h>
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#include <asm/asm-offsets.h>
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21
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-
#if defined(CONFIG_CPU_PJ4)
22
+
#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B)
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#define PJ4(code...) code
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#define XSC(code...)
25
-
#else
25
+
#elif defined(CONFIG_CPU_MOHAWK) || \
26
+
defined(CONFIG_CPU_XSC3) || \
27
+
defined(CONFIG_CPU_XSCALE)
26
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#define PJ4(code...)
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#define XSC(code...) code
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+
#else
31
+
#error "Unsupported iWMMXt architecture"
28
32
#endif
29
33
30
34
#define MMX_WR0 (0x00)
+39
-3
arch/arm/kernel/pj4-cp0.c
+39
-3
arch/arm/kernel/pj4-cp0.c
···
45
45
return NOTIFY_DONE;
46
46
}
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47
48
-
static struct notifier_block iwmmxt_notifier_block = {
48
+
static struct notifier_block __maybe_unused iwmmxt_notifier_block = {
49
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.notifier_call = iwmmxt_do,
50
50
};
51
51
···
72
72
: "=r" (temp) : "r" (value));
73
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}
74
74
75
+
static int __init pj4_get_iwmmxt_version(void)
76
+
{
77
+
u32 cp_access, wcid;
78
+
79
+
cp_access = pj4_cp_access_read();
80
+
pj4_cp_access_write(cp_access | 0xf);
81
+
82
+
/* check if coprocessor 0 and 1 are available */
83
+
if ((pj4_cp_access_read() & 0xf) != 0xf) {
84
+
pj4_cp_access_write(cp_access);
85
+
return -ENODEV;
86
+
}
87
+
88
+
/* read iWMMXt coprocessor id register p1, c0 */
89
+
__asm__ __volatile__ ("mrc p1, 0, %0, c0, c0, 0\n" : "=r" (wcid));
90
+
91
+
pj4_cp_access_write(cp_access);
92
+
93
+
/* iWMMXt v1 */
94
+
if ((wcid & 0xffffff00) == 0x56051000)
95
+
return 1;
96
+
/* iWMMXt v2 */
97
+
if ((wcid & 0xffffff00) == 0x56052000)
98
+
return 2;
99
+
100
+
return -EINVAL;
101
+
}
75
102
76
103
/*
77
104
* Disable CP0/CP1 on boot, and let call_fpe() and the iWMMXt lazy
···
106
79
*/
107
80
static int __init pj4_cp0_init(void)
108
81
{
109
-
u32 cp_access;
82
+
u32 __maybe_unused cp_access;
83
+
int vers;
110
84
111
85
if (!cpu_is_pj4())
112
86
return 0;
113
87
88
+
vers = pj4_get_iwmmxt_version();
89
+
if (vers < 0)
90
+
return 0;
91
+
92
+
#ifndef CONFIG_IWMMXT
93
+
pr_info("PJ4 iWMMXt coprocessor detected, but kernel support is missing.\n");
94
+
#else
114
95
cp_access = pj4_cp_access_read() & ~0xf;
115
96
pj4_cp_access_write(cp_access);
116
97
117
-
printk(KERN_INFO "PJ4 iWMMXt coprocessor enabled.\n");
98
+
pr_info("PJ4 iWMMXt v%d coprocessor enabled.\n", vers);
118
99
elf_hwcap |= HWCAP_IWMMXT;
119
100
thread_register_notifier(&iwmmxt_notifier_block);
101
+
#endif
120
102
121
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return 0;
122
104
}