diff options
Diffstat (limited to 'arch/arc/plat-eznps/mtm.c')
-rw-r--r-- | arch/arc/plat-eznps/mtm.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/arch/arc/plat-eznps/mtm.c b/arch/arc/plat-eznps/mtm.c new file mode 100644 index 000000000..aaaaffd3d --- /dev/null +++ b/arch/arc/plat-eznps/mtm.c @@ -0,0 +1,133 @@ +/* + * Copyright(c) 2015 EZchip Technologies. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + */ + +#include <linux/smp.h> +#include <linux/io.h> +#include <linux/log2.h> +#include <asm/arcregs.h> +#include <plat/mtm.h> +#include <plat/smp.h> + +#define MT_CTRL_HS_CNT 0xFF +#define MT_CTRL_ST_CNT 0xF +#define NPS_NUM_HW_THREADS 0x10 + +static void mtm_init_nat(int cpu) +{ + struct nps_host_reg_mtm_cfg mtm_cfg; + struct nps_host_reg_aux_udmc udmc; + int log_nat, nat = 0, i, t; + + /* Iterate core threads and update nat */ + for (i = 0, t = cpu; i < NPS_NUM_HW_THREADS; i++, t++) + nat += test_bit(t, cpumask_bits(cpu_possible_mask)); + + log_nat = ilog2(nat); + + udmc.value = read_aux_reg(CTOP_AUX_UDMC); + udmc.nat = log_nat; + write_aux_reg(CTOP_AUX_UDMC, udmc.value); + + mtm_cfg.value = ioread32be(MTM_CFG(cpu)); + mtm_cfg.nat = log_nat; + iowrite32be(mtm_cfg.value, MTM_CFG(cpu)); +} + +static void mtm_init_thread(int cpu) +{ + int i, tries = 5; + struct nps_host_reg_thr_init thr_init; + struct nps_host_reg_thr_init_sts thr_init_sts; + + /* Set thread init register */ + thr_init.value = 0; + iowrite32be(thr_init.value, MTM_THR_INIT(cpu)); + thr_init.thr_id = NPS_CPU_TO_THREAD_NUM(cpu); + thr_init.str = 1; + iowrite32be(thr_init.value, MTM_THR_INIT(cpu)); + + /* Poll till thread init is done */ + for (i = 0; i < tries; i++) { + thr_init_sts.value = ioread32be(MTM_THR_INIT_STS(cpu)); + if (thr_init_sts.thr_id == thr_init.thr_id) { + if (thr_init_sts.bsy) + continue; + else if (thr_init_sts.err) + pr_warn("Failed to thread init cpu %u\n", cpu); + break; + } + + pr_warn("Wrong thread id in thread init for cpu %u\n", cpu); + break; + } + + if (i == tries) + pr_warn("Got thread init timeout for cpu %u\n", cpu); +} + +int mtm_enable_thread(int cpu) +{ + struct nps_host_reg_mtm_cfg mtm_cfg; + + if (NPS_CPU_TO_THREAD_NUM(cpu) == 0) + return 1; + + /* Enable thread in mtm */ + mtm_cfg.value = ioread32be(MTM_CFG(cpu)); + mtm_cfg.ten |= (1 << (NPS_CPU_TO_THREAD_NUM(cpu))); + iowrite32be(mtm_cfg.value, MTM_CFG(cpu)); + + return 0; +} + +void mtm_enable_core(unsigned int cpu) +{ + int i; + struct nps_host_reg_aux_mt_ctrl mt_ctrl; + struct nps_host_reg_mtm_cfg mtm_cfg; + + if (NPS_CPU_TO_THREAD_NUM(cpu) != 0) + return; + + /* Initialize Number of Active Threads */ + mtm_init_nat(cpu); + + /* Initialize mtm_cfg */ + mtm_cfg.value = ioread32be(MTM_CFG(cpu)); + mtm_cfg.ten = 1; + iowrite32be(mtm_cfg.value, MTM_CFG(cpu)); + + /* Initialize all other threads in core */ + for (i = 1; i < NPS_NUM_HW_THREADS; i++) + mtm_init_thread(cpu + i); + + + /* Enable HW schedule, stall counter, mtm */ + mt_ctrl.value = 0; + mt_ctrl.hsen = 1; + mt_ctrl.hs_cnt = MT_CTRL_HS_CNT; + mt_ctrl.sten = 1; + mt_ctrl.st_cnt = MT_CTRL_ST_CNT; + mt_ctrl.mten = 1; + write_aux_reg(CTOP_AUX_MT_CTRL, mt_ctrl.value); + + /* + * HW scheduling mechanism will start working + * Only after call to instruction "schd.rw". + * cpu_relax() calls "schd.rw" instruction. + */ + cpu_relax(); +} |