From 5a3e7c02d84fd31e6a2b1b242612363b6131a09e Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Wed, 3 Feb 2016 03:15:33 +0000 Subject: [PATCH] MIPS: smp-cps: Support MIPSr6 Virtual Processors Introduce support for bringing up Virtual Processors in MIPSr6 systems as CPUs, much like their VPE parallel from the now-deprecated MT ASE. The existing mips_cps_boot_vpes function fits the MIPSr6 architecture pretty well - it can now simply write the mask of running VPs to the VC_RUN register, rather than looping through each & starting or stopping as appropriate as is done for VPEs from the MT ASE. Thus the VP support is in general an extension & simplification of the existing MT ASE VPE (aka SMVP) support. Signed-off-by: Paul Burton Cc: Matt Redfearn Cc: Rusty Russell Cc: Maciej W. Rozycki Cc: Niklas Cassel Cc: Ezequiel Garcia Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12339/ Signed-off-by: Ralf Baechle --- arch/mips/Kconfig | 2 +- arch/mips/include/asm/cpu-info.h | 4 +-- arch/mips/kernel/cps-vec.S | 53 ++++++++++++++++++++++++++++++++++++++-- arch/mips/kernel/smp-cps.c | 35 +++++++++++++++++++++++--- 4 files changed, 85 insertions(+), 9 deletions(-) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 882e73c3..e77a439 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -2282,7 +2282,7 @@ config MIPS_CMP config MIPS_CPS bool "MIPS Coherent Processing System support" - depends on SYS_SUPPORTS_MIPS_CPS && !CPU_MIPSR6 + depends on SYS_SUPPORTS_MIPS_CPS select MIPS_CM select MIPS_CPC select MIPS_CPS_PM if HOTPLUG_CPU diff --git a/arch/mips/include/asm/cpu-info.h b/arch/mips/include/asm/cpu-info.h index af12c1f..9ec8168 100644 --- a/arch/mips/include/asm/cpu-info.h +++ b/arch/mips/include/asm/cpu-info.h @@ -68,7 +68,7 @@ struct cpuinfo_mips { #ifdef CONFIG_64BIT int vmbits; /* Virtual memory size in bits */ #endif -#ifdef CONFIG_MIPS_MT_SMP +#if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_CPU_MIPSR6) /* * There is not necessarily a 1:1 mapping of VPE num to CPU number * in particular on multi-core systems. @@ -125,7 +125,7 @@ struct proc_cpuinfo_notifier_args { unsigned long n; }; -#ifdef CONFIG_MIPS_MT_SMP +#if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_CPU_MIPSR6) # define cpu_vpe_id(cpuinfo) ((cpuinfo)->vpe_id) #else # define cpu_vpe_id(cpuinfo) ({ (void)cpuinfo; 0; }) diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S index 4849cbd..c28138d 100644 --- a/arch/mips/kernel/cps-vec.S +++ b/arch/mips/kernel/cps-vec.S @@ -18,9 +18,12 @@ #include #include +#define GCR_CPC_BASE_OFS 0x0088 #define GCR_CL_COHERENCE_OFS 0x2008 #define GCR_CL_ID_OFS 0x2028 +#define CPC_CL_VC_RUN_OFS 0x2028 + .extern mips_cm_base .set noreorder @@ -60,6 +63,26 @@ nop .endm + /* + * Set dest to non-zero if the core supports MIPSr6 multithreading + * (ie. VPs), else zero. If MIPSr6 multithreading is not supported then + * branch to nomt. + */ + .macro has_vp dest, nomt + mfc0 \dest, CP0_CONFIG, 1 + bgez \dest, \nomt + mfc0 \dest, CP0_CONFIG, 2 + bgez \dest, \nomt + mfc0 \dest, CP0_CONFIG, 3 + bgez \dest, \nomt + mfc0 \dest, CP0_CONFIG, 4 + bgez \dest, \nomt + mfc0 \dest, CP0_CONFIG, 5 + andi \dest, \dest, MIPS_CONF5_VP + beqz \dest, \nomt + nop + .endm + /* Calculate an uncached address for the CM GCRs */ .macro cmgcrb dest .set push @@ -296,7 +319,17 @@ LEAF(mips_cps_get_bootcfg) /* Calculate this VPEs ID. If the core doesn't support MT use 0 */ li t9, 0 -#ifdef CONFIG_MIPS_MT_SMP +#if defined(CONFIG_CPU_MIPSR6) + has_vp ta2, 1f + + /* + * Assume non-contiguous numbering. Perhaps some day we'll need + * to handle contiguous VP numbering, but no such systems yet + * exist. + */ + mfc0 t9, $3, 1 + andi t9, t9, 0xff +#elif defined(CONFIG_MIPS_MT_SMP) has_mt ta2, 1f /* Find the number of VPEs present in the core */ @@ -332,7 +365,23 @@ LEAF(mips_cps_boot_vpes) PTR_L ta2, COREBOOTCFG_VPEMASK(a0) PTR_L ta3, COREBOOTCFG_VPECONFIG(a0) -#ifdef CONFIG_MIPS_MT +#if defined(CONFIG_CPU_MIPSR6) + + has_vp t0, 5f + + /* Find base address of CPC */ + cmgcrb t3 + PTR_L t1, GCR_CPC_BASE_OFS(t3) + PTR_LI t2, ~0x7fff + and t1, t1, t2 + PTR_LI t2, UNCAC_BASE + PTR_ADD t1, t1, t2 + + /* Set VC_RUN to the VPE mask */ + PTR_S ta2, CPC_CL_VC_RUN_OFS(t1) + ehb + +#elif defined(CONFIG_MIPS_MT) .set push .set mt diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c index 1a289db..0651217 100644 --- a/arch/mips/kernel/smp-cps.c +++ b/arch/mips/kernel/smp-cps.c @@ -35,7 +35,8 @@ static unsigned core_vpe_count(unsigned core) { unsigned cfg; - if (!config_enabled(CONFIG_MIPS_MT_SMP) || !cpu_has_mipsmt) + if ((!config_enabled(CONFIG_MIPS_MT_SMP) || !cpu_has_mipsmt) + && (!config_enabled(CONFIG_CPU_MIPSR6) || !cpu_has_vp)) return 1; mips_cm_lock_other(core, 0); @@ -47,11 +48,12 @@ static unsigned core_vpe_count(unsigned core) static void __init cps_smp_setup(void) { unsigned int ncores, nvpes, core_vpes; + unsigned long core_entry; int c, v; /* Detect & record VPE topology */ ncores = mips_cm_numcores(); - pr_info("VPE topology "); + pr_info("%s topology ", cpu_has_mips_r6 ? "VP" : "VPE"); for (c = nvpes = 0; c < ncores; c++) { core_vpes = core_vpe_count(c); pr_cont("%c%u", c ? ',' : '{', core_vpes); @@ -62,7 +64,7 @@ static void __init cps_smp_setup(void) for (v = 0; v < min_t(int, core_vpes, NR_CPUS - nvpes); v++) { cpu_data[nvpes + v].core = c; -#ifdef CONFIG_MIPS_MT_SMP +#if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_CPU_MIPSR6) cpu_data[nvpes + v].vpe_id = v; #endif } @@ -91,6 +93,11 @@ static void __init cps_smp_setup(void) /* Make core 0 coherent with everything */ write_gcr_cl_coherence(0xff); + if (mips_cm_revision() >= CM_REV_CM3) { + core_entry = CKSEG1ADDR((unsigned long)mips_cps_core_entry); + write_gcr_bev_base(core_entry); + } + #ifdef CONFIG_MIPS_MT_FPAFF /* If we have an FPU, enroll ourselves in the FPU-full mask */ if (cpu_has_fpu) @@ -213,6 +220,18 @@ static void boot_core(unsigned core) if (mips_cpc_present()) { /* Reset the core */ mips_cpc_lock_other(core); + + if (mips_cm_revision() >= CM_REV_CM3) { + /* Run VP0 following the reset */ + write_cpc_co_vp_run(0x1); + + /* + * Ensure that the VP_RUN register is written before the + * core leaves reset. + */ + wmb(); + } + write_cpc_co_cmd(CPC_Cx_CMD_RESET); timeout = 100; @@ -262,6 +281,7 @@ static void cps_boot_secondary(int cpu, struct task_struct *idle) unsigned vpe_id = cpu_vpe_id(&cpu_data[cpu]); struct core_boot_config *core_cfg = &mips_cps_core_bootcfg[core]; struct vpe_boot_config *vpe_cfg = &core_cfg->vpe_config[vpe_id]; + unsigned long core_entry; unsigned int remote; int err; @@ -279,6 +299,13 @@ static void cps_boot_secondary(int cpu, struct task_struct *idle) goto out; } + if (cpu_has_vp) { + mips_cm_lock_other(core, vpe_id); + core_entry = CKSEG1ADDR((unsigned long)mips_cps_core_entry); + write_gcr_co_reset_base(core_entry); + mips_cm_unlock_other(); + } + if (core != current_cpu_data.core) { /* Boot a VPE on another powered up core */ for (remote = 0; remote < NR_CPUS; remote++) { @@ -296,7 +323,7 @@ static void cps_boot_secondary(int cpu, struct task_struct *idle) goto out; } - BUG_ON(!cpu_has_mipsmt); + BUG_ON(!cpu_has_mipsmt && !cpu_has_vp); /* Boot a VPE on this core */ mips_cps_boot_vpes(core_cfg, vpe_id); -- 2.7.4