xref: /linux/arch/sh/kernel/cpu/sh4/probe.c (revision 4bedea94545165364618d403d03b61d797acba0b)
1 /*
2  * arch/sh/kernel/cpu/sh4/probe.c
3  *
4  * CPU Subtype Probing for SH-4.
5  *
6  * Copyright (C) 2001, 2002, 2003, 2004  Paul Mundt
7  * Copyright (C) 2003  Richard Curnow
8  *
9  * This file is subject to the terms and conditions of the GNU General Public
10  * License.  See the file "COPYING" in the main directory of this archive
11  * for more details.
12  */
13 
14 #include <linux/init.h>
15 #include <asm/processor.h>
16 #include <asm/cache.h>
17 #include <asm/io.h>
18 
19 int __init detect_cpu_and_cache_system(void)
20 {
21 	unsigned long pvr, prr, cvr;
22 	unsigned long size;
23 
24 	static unsigned long sizes[16] = {
25 		[1] = (1 << 12),
26 		[2] = (1 << 13),
27 		[4] = (1 << 14),
28 		[8] = (1 << 15),
29 		[9] = (1 << 16)
30 	};
31 
32 	pvr = (ctrl_inl(CCN_PVR) >> 8) & 0xffff;
33 	prr = (ctrl_inl(CCN_PRR) >> 4) & 0xff;
34 	cvr = (ctrl_inl(CCN_CVR));
35 
36 	/*
37 	 * Setup some sane SH-4 defaults for the icache
38 	 */
39 	cpu_data->icache.way_incr	= (1 << 13);
40 	cpu_data->icache.entry_shift	= 5;
41 	cpu_data->icache.entry_mask	= 0x1fe0;
42 	cpu_data->icache.sets		= 256;
43 	cpu_data->icache.ways		= 1;
44 	cpu_data->icache.linesz		= L1_CACHE_BYTES;
45 
46 	/*
47 	 * And again for the dcache ..
48 	 */
49 	cpu_data->dcache.way_incr	= (1 << 14);
50 	cpu_data->dcache.entry_shift	= 5;
51 	cpu_data->dcache.entry_mask	= 0x3fe0;
52 	cpu_data->dcache.sets		= 512;
53 	cpu_data->dcache.ways		= 1;
54 	cpu_data->dcache.linesz		= L1_CACHE_BYTES;
55 
56 	/* Set the FPU flag, virtually all SH-4's have one */
57 	cpu_data->flags |= CPU_HAS_FPU;
58 
59 	/*
60 	 * Probe the underlying processor version/revision and
61 	 * adjust cpu_data setup accordingly.
62 	 */
63 	switch (pvr) {
64 	case 0x205:
65 		cpu_data->type = CPU_SH7750;
66 		cpu_data->flags |= CPU_HAS_P2_FLUSH_BUG | CPU_HAS_PERF_COUNTER;
67 		break;
68 	case 0x206:
69 		cpu_data->type = CPU_SH7750S;
70 		cpu_data->flags |= CPU_HAS_P2_FLUSH_BUG | CPU_HAS_PERF_COUNTER;
71 		break;
72 	case 0x1100:
73 		cpu_data->type = CPU_SH7751;
74 		break;
75 	case 0x2000:
76 		cpu_data->type = CPU_SH73180;
77 		cpu_data->icache.ways = 4;
78 		cpu_data->dcache.ways = 4;
79 		cpu_data->flags &= ~CPU_HAS_FPU;
80 		break;
81 	case 0x8000:
82 		cpu_data->type = CPU_ST40RA;
83 		break;
84 	case 0x8100:
85 		cpu_data->type = CPU_ST40GX1;
86 		break;
87 	case 0x700:
88 		cpu_data->type = CPU_SH4_501;
89 		cpu_data->icache.ways = 2;
90 		cpu_data->dcache.ways = 2;
91 
92 		/* No FPU on the SH4-500 series.. */
93 		cpu_data->flags &= ~CPU_HAS_FPU;
94 		break;
95 	case 0x600:
96 		cpu_data->type = CPU_SH4_202;
97 		cpu_data->icache.ways = 2;
98 		cpu_data->dcache.ways = 2;
99 		break;
100 	case 0x500 ... 0x501:
101 		switch (prr) {
102 		    case 0x10: cpu_data->type = CPU_SH7750R; break;
103 		    case 0x11: cpu_data->type = CPU_SH7751R; break;
104 		    case 0x50: cpu_data->type = CPU_SH7760;  break;
105 		}
106 
107 		cpu_data->icache.ways = 2;
108 		cpu_data->dcache.ways = 2;
109 
110 		break;
111 	default:
112 		cpu_data->type = CPU_SH_NONE;
113 		break;
114 	}
115 
116 	/*
117 	 * On anything that's not a direct-mapped cache, look to the CVR
118 	 * for I/D-cache specifics.
119 	 */
120 	if (cpu_data->icache.ways > 1) {
121 		size = sizes[(cvr >> 20) & 0xf];
122 		cpu_data->icache.way_incr	= (size >> 1);
123 		cpu_data->icache.sets		= (size >> 6);
124 		cpu_data->icache.entry_mask	=
125 			(cpu_data->icache.way_incr - (1 << 5));
126 	}
127 
128 	if (cpu_data->dcache.ways > 1) {
129 		size = sizes[(cvr >> 16) & 0xf];
130 		cpu_data->dcache.way_incr	= (size >> 1);
131 		cpu_data->dcache.sets		= (size >> 6);
132 		cpu_data->dcache.entry_mask	=
133 			(cpu_data->dcache.way_incr - (1 << 5));
134 	}
135 
136 	return 0;
137 }
138 
139