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 000000000000..aaaaffd3d940
--- /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();
+}