1 /*
2 * Support for MicroBlaze PVR (processor version register)
3 *
4 * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
5 * Copyright (C) 2007-2009 PetaLogix
6 * Copyright (C) 2007 John Williams <john.williams@petalogix.com>
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/compiler.h>
15 #include <asm/exceptions.h>
16 #include <asm/pvr.h>
17
18 /*
19 * Until we get an assembler that knows about the pvr registers,
20 * this horrible cruft will have to do.
21 * That hardcoded opcode is mfs r3, rpvrNN
22 */
23
24 #define get_single_pvr(pvrid, val) \
25 { \
26 register unsigned tmp __asm__("r3"); \
27 tmp = 0x0; /* Prevent warning about unused */ \
28 __asm__ __volatile__ ( \
29 "mfs %0, rpvr" #pvrid ";" \
30 : "=r" (tmp) : : "memory"); \
31 val = tmp; \
32 }
33
34 /*
35 * Does the CPU support the PVR register?
36 * return value:
37 * 0: no PVR
38 * 1: simple PVR
39 * 2: full PVR
40 *
41 * This must work on all CPU versions, including those before the
42 * PVR was even an option.
43 */
44
45 int cpu_has_pvr(void)
46 {
47 unsigned long flags;
48 unsigned pvr0;
49
50 local_save_flags(flags);
51
52 /* PVR bit in MSR tells us if there is any support */
53 if (!(flags & PVR_MSR_BIT))
54 return 0;
55
56 get_single_pvr(0, pvr0);
57 pr_debug("%s: pvr0 is 0x%08x\n", __func__, pvr0);
58
59 if (pvr0 & PVR0_PVR_FULL_MASK)
60 return 1;
61
62 /* for partial PVR use static cpuinfo */
63 return 2;
64 }
65
66 void get_pvr(struct pvr_s *p)
67 {
68 get_single_pvr(0, p->pvr[0]);
69 get_single_pvr(1, p->pvr[1]);
70 get_single_pvr(2, p->pvr[2]);
71 get_single_pvr(3, p->pvr[3]);
72 get_single_pvr(4, p->pvr[4]);
73 get_single_pvr(5, p->pvr[5]);
74 get_single_pvr(6, p->pvr[6]);
75 get_single_pvr(7, p->pvr[7]);
76 get_single_pvr(8, p->pvr[8]);
77 get_single_pvr(9, p->pvr[9]);
78 get_single_pvr(10, p->pvr[10]);
79 get_single_pvr(11, p->pvr[11]);
80 }