diff options
| author | Paul Burton <paul.burton@imgtec.com> | 2016-02-03 06:15:32 +0300 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2016-05-13 15:01:50 +0300 |
| commit | 87a70bcdb41008decfcf7c217e26b0bcd7f52642 (patch) | |
| tree | af92be6eadac4c5363881d68ee36954ded88b2ad /arch/mips/kernel/cps-vec.S | |
| parent | f12401d7219f5a1e361ded834016e5777a10262b (diff) | |
| download | linux-87a70bcdb41008decfcf7c217e26b0bcd7f52642.tar.xz | |
MIPS: smp-cps: Skip core setup if coherent
In preparation for supporting MIPSr6 multithreading (ie. VPs) which will
begin execution from the core reset vector, skip core level setup if the
core is already coherent. This is never the case when a core is first
started, since boot_core explicitly clears the cores GCR_Cx_COH_EN
register, and always the case when secondary VPs start since the first
VP to start will have enabled coherence after initialising the core &
its caches.
One notable side effect of this patch is that eva_init gets called
slightly earlier, prior to mips_cps_core_init rather than after it.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12338/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/cps-vec.S')
| -rw-r--r-- | arch/mips/kernel/cps-vec.S | 39 |
1 files changed, 24 insertions, 15 deletions
diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S index 2613de9bcb2d..4849cbd47ccc 100644 --- a/arch/mips/kernel/cps-vec.S +++ b/arch/mips/kernel/cps-vec.S @@ -101,43 +101,52 @@ not_nmi: li t0, ST0_CU1 | ST0_CU0 | ST0_BEV | STATUS_BITDEPS mtc0 t0, CP0_STATUS + /* Skip cache & coherence setup if we're already coherent */ + cmgcrb v1 + lw s7, GCR_CL_COHERENCE_OFS(v1) + bnez s7, 1f + nop + /* Initialize the L1 caches */ jal mips_cps_cache_init nop + /* Enter the coherent domain */ + li t0, 0xff + sw t0, GCR_CL_COHERENCE_OFS(v1) + ehb + /* Set Kseg0 CCA to that in s0 */ - mfc0 t0, CP0_CONFIG +1: mfc0 t0, CP0_CONFIG ori t0, 0x7 xori t0, 0x7 or t0, t0, s0 mtc0 t0, CP0_CONFIG ehb - /* Enter the coherent domain */ - cmgcrb v1 - li t0, 0xff - sw t0, GCR_CL_COHERENCE_OFS(v1) - ehb - /* Jump to kseg0 */ PTR_LA t0, 1f jr t0 nop /* - * We're up, cached & coherent. Perform any further required core-level - * initialisation. + * We're up, cached & coherent. Perform any EVA initialization necessary + * before we access memory. */ -1: jal mips_cps_core_init - nop - - /* Do any EVA initialization if necessary */ - eva_init +1: eva_init /* Retrieve boot configuration pointers */ jal mips_cps_get_bootcfg nop + /* Skip core-level init if we started up coherent */ + bnez s7, 1f + nop + + /* Perform any further required core-level initialisation */ + jal mips_cps_core_init + nop + /* * Boot any other VPEs within this core that should be online, and * deactivate this VPE if it should be offline. @@ -147,7 +156,7 @@ not_nmi: move a0, v0 /* Off we go! */ - PTR_L t1, VPEBOOTCFG_PC(v1) +1: PTR_L t1, VPEBOOTCFG_PC(v1) PTR_L gp, VPEBOOTCFG_GP(v1) PTR_L sp, VPEBOOTCFG_SP(v1) jr t1 |