linux/arch/mips/include/asm/cpu-features.h
David Daney 6dd9344cfc MIPS: Implement Read Inhibit/eXecute Inhibit
The SmartMIPS ASE specifies how Read Inhibit (RI) and eXecute Inhibit
(XI) bits in the page tables work.  The upper two bits of EntryLo{0,1}
are RI and XI when the feature is enabled in the PageGrain register.
SmartMIPS only covers 32-bit systems.  Cavium Octeon+ extends this to
64-bit systems by continuing to place the RI and XI bits in the top of
EntryLo even when EntryLo is 64-bits wide.

Because we need to carry the RI and XI bits in the PTE, the layout of
the PTE is changed.  There is a two instruction overhead in the TLB
refill hot path to get the EntryLo bits into the proper position.
Also the TLB load exception has to probe the TLB to check if RI or XI
caused the exception.

Also of note is that the layout of the PTE bits is done at compile and
runtime rather than statically.  In the 32-bit case this allows for
the same number of PFN bits as before the patch as the _PAGE_HUGE is
not supported in 32-bit kernels (we have _PAGE_NO_EXEC and
_PAGE_NO_READ instead of _PAGE_READ and _PAGE_HUGE).

The patch is tested on Cavium Octeon+, but should also work on 32-bit
systems with the Smart-MIPS ASE.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/952/
Patchwork: http://patchwork.linux-mips.org/patch/956/
Patchwork: http://patchwork.linux-mips.org/patch/962/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-02-27 12:53:26 +01:00

254 lines
7.4 KiB
C

/*
* 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.
*
* Copyright (C) 2003, 2004 Ralf Baechle
* Copyright (C) 2004 Maciej W. Rozycki
*/
#ifndef __ASM_CPU_FEATURES_H
#define __ASM_CPU_FEATURES_H
#include <asm/cpu.h>
#include <asm/cpu-info.h>
#include <cpu-feature-overrides.h>
#ifndef current_cpu_type
#define current_cpu_type() current_cpu_data.cputype
#endif
/*
* SMP assumption: Options of CPU 0 are a superset of all processors.
* This is true for all known MIPS systems.
*/
#ifndef cpu_has_tlb
#define cpu_has_tlb (cpu_data[0].options & MIPS_CPU_TLB)
#endif
#ifndef cpu_has_4kex
#define cpu_has_4kex (cpu_data[0].options & MIPS_CPU_4KEX)
#endif
#ifndef cpu_has_3k_cache
#define cpu_has_3k_cache (cpu_data[0].options & MIPS_CPU_3K_CACHE)
#endif
#define cpu_has_6k_cache 0
#define cpu_has_8k_cache 0
#ifndef cpu_has_4k_cache
#define cpu_has_4k_cache (cpu_data[0].options & MIPS_CPU_4K_CACHE)
#endif
#ifndef cpu_has_tx39_cache
#define cpu_has_tx39_cache (cpu_data[0].options & MIPS_CPU_TX39_CACHE)
#endif
#ifndef cpu_has_octeon_cache
#define cpu_has_octeon_cache 0
#endif
#ifndef cpu_has_fpu
#define cpu_has_fpu (current_cpu_data.options & MIPS_CPU_FPU)
#define raw_cpu_has_fpu (raw_current_cpu_data.options & MIPS_CPU_FPU)
#else
#define raw_cpu_has_fpu cpu_has_fpu
#endif
#ifndef cpu_has_32fpr
#define cpu_has_32fpr (cpu_data[0].options & MIPS_CPU_32FPR)
#endif
#ifndef cpu_has_counter
#define cpu_has_counter (cpu_data[0].options & MIPS_CPU_COUNTER)
#endif
#ifndef cpu_has_watch
#define cpu_has_watch (cpu_data[0].options & MIPS_CPU_WATCH)
#endif
#ifndef cpu_has_divec
#define cpu_has_divec (cpu_data[0].options & MIPS_CPU_DIVEC)
#endif
#ifndef cpu_has_vce
#define cpu_has_vce (cpu_data[0].options & MIPS_CPU_VCE)
#endif
#ifndef cpu_has_cache_cdex_p
#define cpu_has_cache_cdex_p (cpu_data[0].options & MIPS_CPU_CACHE_CDEX_P)
#endif
#ifndef cpu_has_cache_cdex_s
#define cpu_has_cache_cdex_s (cpu_data[0].options & MIPS_CPU_CACHE_CDEX_S)
#endif
#ifndef cpu_has_prefetch
#define cpu_has_prefetch (cpu_data[0].options & MIPS_CPU_PREFETCH)
#endif
#ifndef cpu_has_mcheck
#define cpu_has_mcheck (cpu_data[0].options & MIPS_CPU_MCHECK)
#endif
#ifndef cpu_has_ejtag
#define cpu_has_ejtag (cpu_data[0].options & MIPS_CPU_EJTAG)
#endif
#ifndef cpu_has_llsc
#define cpu_has_llsc (cpu_data[0].options & MIPS_CPU_LLSC)
#endif
#ifndef kernel_uses_llsc
#define kernel_uses_llsc cpu_has_llsc
#endif
#ifndef cpu_has_mips16
#define cpu_has_mips16 (cpu_data[0].ases & MIPS_ASE_MIPS16)
#endif
#ifndef cpu_has_mdmx
#define cpu_has_mdmx (cpu_data[0].ases & MIPS_ASE_MDMX)
#endif
#ifndef cpu_has_mips3d
#define cpu_has_mips3d (cpu_data[0].ases & MIPS_ASE_MIPS3D)
#endif
#ifndef cpu_has_smartmips
#define cpu_has_smartmips (cpu_data[0].ases & MIPS_ASE_SMARTMIPS)
#endif
#ifndef kernel_uses_smartmips_rixi
#define kernel_uses_smartmips_rixi 0
#endif
#ifndef cpu_has_vtag_icache
#define cpu_has_vtag_icache (cpu_data[0].icache.flags & MIPS_CACHE_VTAG)
#endif
#ifndef cpu_has_dc_aliases
#define cpu_has_dc_aliases (cpu_data[0].dcache.flags & MIPS_CACHE_ALIASES)
#endif
#ifndef cpu_has_ic_fills_f_dc
#define cpu_has_ic_fills_f_dc (cpu_data[0].icache.flags & MIPS_CACHE_IC_F_DC)
#endif
#ifndef cpu_has_pindexed_dcache
#define cpu_has_pindexed_dcache (cpu_data[0].dcache.flags & MIPS_CACHE_PINDEX)
#endif
/*
* I-Cache snoops remote store. This only matters on SMP. Some multiprocessors
* such as the R10000 have I-Caches that snoop local stores; the embedded ones
* don't. For maintaining I-cache coherency this means we need to flush the
* D-cache all the way back to whever the I-cache does refills from, so the
* I-cache has a chance to see the new data at all. Then we have to flush the
* I-cache also.
* Note we may have been rescheduled and may no longer be running on the CPU
* that did the store so we can't optimize this into only doing the flush on
* the local CPU.
*/
#ifndef cpu_icache_snoops_remote_store
#ifdef CONFIG_SMP
#define cpu_icache_snoops_remote_store (cpu_data[0].icache.flags & MIPS_IC_SNOOPS_REMOTE)
#else
#define cpu_icache_snoops_remote_store 1
#endif
#endif
# ifndef cpu_has_mips32r1
# define cpu_has_mips32r1 (cpu_data[0].isa_level & MIPS_CPU_ISA_M32R1)
# endif
# ifndef cpu_has_mips32r2
# define cpu_has_mips32r2 (cpu_data[0].isa_level & MIPS_CPU_ISA_M32R2)
# endif
# ifndef cpu_has_mips64r1
# define cpu_has_mips64r1 (cpu_data[0].isa_level & MIPS_CPU_ISA_M64R1)
# endif
# ifndef cpu_has_mips64r2
# define cpu_has_mips64r2 (cpu_data[0].isa_level & MIPS_CPU_ISA_M64R2)
# endif
/*
* Shortcuts ...
*/
#define cpu_has_mips32 (cpu_has_mips32r1 | cpu_has_mips32r2)
#define cpu_has_mips64 (cpu_has_mips64r1 | cpu_has_mips64r2)
#define cpu_has_mips_r1 (cpu_has_mips32r1 | cpu_has_mips64r1)
#define cpu_has_mips_r2 (cpu_has_mips32r2 | cpu_has_mips64r2)
#define cpu_has_mips_r (cpu_has_mips32r1 | cpu_has_mips32r2 | \
cpu_has_mips64r1 | cpu_has_mips64r2)
#ifndef cpu_has_mips_r2_exec_hazard
#define cpu_has_mips_r2_exec_hazard cpu_has_mips_r2
#endif
/*
* MIPS32, MIPS64, VR5500, IDT32332, IDT32334 and maybe a few other
* pre-MIPS32/MIPS53 processors have CLO, CLZ. For 64-bit kernels
* cpu_has_clo_clz also indicates the availability of DCLO and DCLZ.
*/
# ifndef cpu_has_clo_clz
# define cpu_has_clo_clz cpu_has_mips_r
# endif
#ifndef cpu_has_dsp
#define cpu_has_dsp (cpu_data[0].ases & MIPS_ASE_DSP)
#endif
#ifndef cpu_has_mipsmt
#define cpu_has_mipsmt (cpu_data[0].ases & MIPS_ASE_MIPSMT)
#endif
#ifndef cpu_has_userlocal
#define cpu_has_userlocal (cpu_data[0].options & MIPS_CPU_ULRI)
#endif
#ifdef CONFIG_32BIT
# ifndef cpu_has_nofpuex
# define cpu_has_nofpuex (cpu_data[0].options & MIPS_CPU_NOFPUEX)
# endif
# ifndef cpu_has_64bits
# define cpu_has_64bits (cpu_data[0].isa_level & MIPS_CPU_ISA_64BIT)
# endif
# ifndef cpu_has_64bit_zero_reg
# define cpu_has_64bit_zero_reg (cpu_data[0].isa_level & MIPS_CPU_ISA_64BIT)
# endif
# ifndef cpu_has_64bit_gp_regs
# define cpu_has_64bit_gp_regs 0
# endif
# ifndef cpu_has_64bit_addresses
# define cpu_has_64bit_addresses 0
# endif
# ifndef cpu_vmbits
# define cpu_vmbits 31
# endif
#endif
#ifdef CONFIG_64BIT
# ifndef cpu_has_nofpuex
# define cpu_has_nofpuex 0
# endif
# ifndef cpu_has_64bits
# define cpu_has_64bits 1
# endif
# ifndef cpu_has_64bit_zero_reg
# define cpu_has_64bit_zero_reg 1
# endif
# ifndef cpu_has_64bit_gp_regs
# define cpu_has_64bit_gp_regs 1
# endif
# ifndef cpu_has_64bit_addresses
# define cpu_has_64bit_addresses 1
# endif
# ifndef cpu_vmbits
# define cpu_vmbits cpu_data[0].vmbits
# define __NEED_VMBITS_PROBE
# endif
#endif
#if defined(CONFIG_CPU_MIPSR2_IRQ_VI) && !defined(cpu_has_vint)
# define cpu_has_vint (cpu_data[0].options & MIPS_CPU_VINT)
#elif !defined(cpu_has_vint)
# define cpu_has_vint 0
#endif
#if defined(CONFIG_CPU_MIPSR2_IRQ_EI) && !defined(cpu_has_veic)
# define cpu_has_veic (cpu_data[0].options & MIPS_CPU_VEIC)
#elif !defined(cpu_has_veic)
# define cpu_has_veic 0
#endif
#ifndef cpu_has_inclusive_pcaches
#define cpu_has_inclusive_pcaches (cpu_data[0].options & MIPS_CPU_INCLUSIVE_CACHES)
#endif
#ifndef cpu_dcache_line_size
#define cpu_dcache_line_size() cpu_data[0].dcache.linesz
#endif
#ifndef cpu_icache_line_size
#define cpu_icache_line_size() cpu_data[0].icache.linesz
#endif
#ifndef cpu_scache_line_size
#define cpu_scache_line_size() cpu_data[0].scache.linesz
#endif
#ifndef cpu_hwrena_impl_bits
#define cpu_hwrena_impl_bits 0
#endif
#endif /* __ASM_CPU_FEATURES_H */