android_kernel_xiaomi_sm8350/arch/sh/kernel/cpu/sh3/probe.c
Stuart Menefy cbaa118ecf sh: Preparation for uncached jumps through PMB.
Presently most of the 29-bit physical parts do P1/P2 segmentation
with a 1:1 cached/uncached mapping, jumping between the two to
control the caching behaviour. This provides the basic infrastructure
to maintain this behaviour on 32-bit physical parts that don't map
P1/P2 at all, using a shiny new linker section and corresponding
fixmap entry.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-01-28 13:18:59 +09:00

109 lines
2.8 KiB
C

/*
* arch/sh/kernel/cpu/sh3/probe.c
*
* CPU Subtype Probing for SH-3.
*
* Copyright (C) 1999, 2000 Niibe Yutaka
* Copyright (C) 2002 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <asm/processor.h>
#include <asm/cache.h>
#include <asm/io.h>
int __uses_jump_to_uncached detect_cpu_and_cache_system(void)
{
unsigned long addr0, addr1, data0, data1, data2, data3;
jump_to_uncached();
/*
* Check if the entry shadows or not.
* When shadowed, it's 128-entry system.
* Otherwise, it's 256-entry system.
*/
addr0 = CACHE_OC_ADDRESS_ARRAY + (3 << 12);
addr1 = CACHE_OC_ADDRESS_ARRAY + (1 << 12);
/* First, write back & invalidate */
data0 = ctrl_inl(addr0);
ctrl_outl(data0&~(SH_CACHE_VALID|SH_CACHE_UPDATED), addr0);
data1 = ctrl_inl(addr1);
ctrl_outl(data1&~(SH_CACHE_VALID|SH_CACHE_UPDATED), addr1);
/* Next, check if there's shadow or not */
data0 = ctrl_inl(addr0);
data0 ^= SH_CACHE_VALID;
ctrl_outl(data0, addr0);
data1 = ctrl_inl(addr1);
data2 = data1 ^ SH_CACHE_VALID;
ctrl_outl(data2, addr1);
data3 = ctrl_inl(addr0);
/* Lastly, invaliate them. */
ctrl_outl(data0&~SH_CACHE_VALID, addr0);
ctrl_outl(data2&~SH_CACHE_VALID, addr1);
back_to_cached();
boot_cpu_data.dcache.ways = 4;
boot_cpu_data.dcache.entry_shift = 4;
boot_cpu_data.dcache.linesz = L1_CACHE_BYTES;
boot_cpu_data.dcache.flags = 0;
/*
* 7709A/7729 has 16K cache (256-entry), while 7702 has only
* 2K(direct) 7702 is not supported (yet)
*/
if (data0 == data1 && data2 == data3) { /* Shadow */
boot_cpu_data.dcache.way_incr = (1 << 11);
boot_cpu_data.dcache.entry_mask = 0x7f0;
boot_cpu_data.dcache.sets = 128;
boot_cpu_data.type = CPU_SH7708;
boot_cpu_data.flags |= CPU_HAS_MMU_PAGE_ASSOC;
} else { /* 7709A or 7729 */
boot_cpu_data.dcache.way_incr = (1 << 12);
boot_cpu_data.dcache.entry_mask = 0xff0;
boot_cpu_data.dcache.sets = 256;
boot_cpu_data.type = CPU_SH7729;
#if defined(CONFIG_CPU_SUBTYPE_SH7706)
boot_cpu_data.type = CPU_SH7706;
#endif
#if defined(CONFIG_CPU_SUBTYPE_SH7710)
boot_cpu_data.type = CPU_SH7710;
#endif
#if defined(CONFIG_CPU_SUBTYPE_SH7712)
boot_cpu_data.type = CPU_SH7712;
#endif
#if defined(CONFIG_CPU_SUBTYPE_SH7720)
boot_cpu_data.type = CPU_SH7720;
#endif
#if defined(CONFIG_CPU_SUBTYPE_SH7705)
boot_cpu_data.type = CPU_SH7705;
#if defined(CONFIG_SH7705_CACHE_32KB)
boot_cpu_data.dcache.way_incr = (1 << 13);
boot_cpu_data.dcache.entry_mask = 0x1ff0;
boot_cpu_data.dcache.sets = 512;
ctrl_outl(CCR_CACHE_32KB, CCR3);
#else
ctrl_outl(CCR_CACHE_16KB, CCR3);
#endif
#endif
}
/*
* SH-3 doesn't have separate caches
*/
boot_cpu_data.dcache.flags |= SH_CACHE_COMBINED;
boot_cpu_data.icache = boot_cpu_data.dcache;
return 0;
}