xref: /openbmc/linux/arch/sh/kernel/cpu/sh2/probe.c (revision 6d99a79c)
1 /*
2  * arch/sh/kernel/cpu/sh2/probe.c
3  *
4  * CPU Subtype Probing for SH-2.
5  *
6  * Copyright (C) 2002 Paul Mundt
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 #include <linux/init.h>
13 #include <linux/of_fdt.h>
14 #include <linux/smp.h>
15 #include <linux/io.h>
16 #include <asm/processor.h>
17 #include <asm/cache.h>
18 
19 #if defined(CONFIG_CPU_J2)
20 extern u32 __iomem *j2_ccr_base;
21 static int __init scan_cache(unsigned long node, const char *uname,
22 			     int depth, void *data)
23 {
24 	if (!of_flat_dt_is_compatible(node, "jcore,cache"))
25 		return 0;
26 
27 	j2_ccr_base = (u32 __iomem *)of_flat_dt_translate_address(node);
28 
29 	return 1;
30 }
31 #endif
32 
33 void __ref cpu_probe(void)
34 {
35 #if defined(CONFIG_CPU_SUBTYPE_SH7619)
36 	boot_cpu_data.type			= CPU_SH7619;
37 	boot_cpu_data.dcache.ways		= 4;
38 	boot_cpu_data.dcache.way_incr	= (1<<12);
39 	boot_cpu_data.dcache.sets		= 256;
40 	boot_cpu_data.dcache.entry_shift	= 4;
41 	boot_cpu_data.dcache.linesz		= L1_CACHE_BYTES;
42 	boot_cpu_data.dcache.flags		= 0;
43 #endif
44 
45 #if defined(CONFIG_CPU_J2)
46 #if defined(CONFIG_SMP)
47 	unsigned cpu = hard_smp_processor_id();
48 #else
49 	unsigned cpu = 0;
50 #endif
51 	if (cpu == 0) of_scan_flat_dt(scan_cache, NULL);
52 	if (j2_ccr_base) __raw_writel(0x80000303, j2_ccr_base + 4*cpu);
53 	if (cpu != 0) return;
54 	boot_cpu_data.type			= CPU_J2;
55 
56 	/* These defaults are appropriate for the original/current
57 	 * J2 cache. Once there is a proper framework for getting cache
58 	 * info from device tree, we should switch to that. */
59 	boot_cpu_data.dcache.ways		= 1;
60 	boot_cpu_data.dcache.sets		= 256;
61 	boot_cpu_data.dcache.entry_shift	= 5;
62 	boot_cpu_data.dcache.linesz		= 32;
63 	boot_cpu_data.dcache.flags		= 0;
64 
65 	boot_cpu_data.flags |= CPU_HAS_CAS_L;
66 #else
67 	/*
68 	 * SH-2 doesn't have separate caches
69 	 */
70 	boot_cpu_data.dcache.flags |= SH_CACHE_COMBINED;
71 #endif
72 	boot_cpu_data.icache = boot_cpu_data.dcache;
73 	boot_cpu_data.family = CPU_FAMILY_SH2;
74 }
75