xref: /openbmc/linux/arch/sh/kernel/cpu/sh2/probe.c (revision 9b93eb47)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arch/sh/kernel/cpu/sh2/probe.c
4  *
5  * CPU Subtype Probing for SH-2.
6  *
7  * Copyright (C) 2002 Paul Mundt
8  */
9 #include <linux/init.h>
10 #include <linux/of_fdt.h>
11 #include <linux/smp.h>
12 #include <linux/io.h>
13 #include <asm/processor.h>
14 #include <asm/cache.h>
15 
16 #if defined(CONFIG_CPU_J2)
17 extern u32 __iomem *j2_ccr_base;
18 static int __init scan_cache(unsigned long node, const char *uname,
19 			     int depth, void *data)
20 {
21 	if (!of_flat_dt_is_compatible(node, "jcore,cache"))
22 		return 0;
23 
24 	j2_ccr_base = (u32 __iomem *)of_flat_dt_translate_address(node);
25 
26 	return 1;
27 }
28 #endif
29 
30 void __ref cpu_probe(void)
31 {
32 #if defined(CONFIG_CPU_SUBTYPE_SH7619)
33 	boot_cpu_data.type			= CPU_SH7619;
34 	boot_cpu_data.dcache.ways		= 4;
35 	boot_cpu_data.dcache.way_incr	= (1<<12);
36 	boot_cpu_data.dcache.sets		= 256;
37 	boot_cpu_data.dcache.entry_shift	= 4;
38 	boot_cpu_data.dcache.linesz		= L1_CACHE_BYTES;
39 	boot_cpu_data.dcache.flags		= 0;
40 #endif
41 
42 #if defined(CONFIG_CPU_J2)
43 #if defined(CONFIG_SMP)
44 	unsigned cpu = hard_smp_processor_id();
45 #else
46 	unsigned cpu = 0;
47 #endif
48 	if (cpu == 0) of_scan_flat_dt(scan_cache, NULL);
49 	if (j2_ccr_base) __raw_writel(0x80000303, j2_ccr_base + 4*cpu);
50 	if (cpu != 0) return;
51 	boot_cpu_data.type			= CPU_J2;
52 
53 	/* These defaults are appropriate for the original/current
54 	 * J2 cache. Once there is a proper framework for getting cache
55 	 * info from device tree, we should switch to that. */
56 	boot_cpu_data.dcache.ways		= 1;
57 	boot_cpu_data.dcache.sets		= 256;
58 	boot_cpu_data.dcache.entry_shift	= 5;
59 	boot_cpu_data.dcache.linesz		= 32;
60 	boot_cpu_data.dcache.flags		= 0;
61 
62 	boot_cpu_data.flags |= CPU_HAS_CAS_L;
63 #else
64 	/*
65 	 * SH-2 doesn't have separate caches
66 	 */
67 	boot_cpu_data.dcache.flags |= SH_CACHE_COMBINED;
68 #endif
69 	boot_cpu_data.icache = boot_cpu_data.dcache;
70 	boot_cpu_data.family = CPU_FAMILY_SH2;
71 }
72