diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-09-11 04:34:46 -0300 |
commit | 863981e96738983919de841ec669e157e6bdaeb0 (patch) | |
tree | d6d89a12e7eb8017837c057935a2271290907f76 /drivers/clocksource/timer-nps.c | |
parent | 8dec7c70575785729a6a9e6719a955e9c545bcab (diff) |
Linux-libre 4.7.1-gnupck-4.7.1-gnu
Diffstat (limited to 'drivers/clocksource/timer-nps.c')
-rw-r--r-- | drivers/clocksource/timer-nps.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-nps.c b/drivers/clocksource/timer-nps.c new file mode 100644 index 000000000..d46108920 --- /dev/null +++ b/drivers/clocksource/timer-nps.c @@ -0,0 +1,98 @@ +/* + * Copyright (c) 2016, Mellanox Technologies. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <linux/interrupt.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/clk.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/cpu.h> +#include <soc/nps/common.h> + +#define NPS_MSU_TICK_LOW 0xC8 +#define NPS_CLUSTER_OFFSET 8 +#define NPS_CLUSTER_NUM 16 + +/* This array is per cluster of CPUs (Each NPS400 cluster got 256 CPUs) */ +static void *nps_msu_reg_low_addr[NPS_CLUSTER_NUM] __read_mostly; + +static unsigned long nps_timer_rate; + +static cycle_t nps_clksrc_read(struct clocksource *clksrc) +{ + int cluster = raw_smp_processor_id() >> NPS_CLUSTER_OFFSET; + + return (cycle_t)ioread32be(nps_msu_reg_low_addr[cluster]); +} + +static void __init nps_setup_clocksource(struct device_node *node, + struct clk *clk) +{ + int ret, cluster; + + for (cluster = 0; cluster < NPS_CLUSTER_NUM; cluster++) + nps_msu_reg_low_addr[cluster] = + nps_host_reg((cluster << NPS_CLUSTER_OFFSET), + NPS_MSU_BLKID, NPS_MSU_TICK_LOW); + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("Couldn't enable parent clock\n"); + return; + } + + nps_timer_rate = clk_get_rate(clk); + + ret = clocksource_mmio_init(nps_msu_reg_low_addr, "EZnps-tick", + nps_timer_rate, 301, 32, nps_clksrc_read); + if (ret) { + pr_err("Couldn't register clock source.\n"); + clk_disable_unprepare(clk); + } +} + +static void __init nps_timer_init(struct device_node *node) +{ + struct clk *clk; + + clk = of_clk_get(node, 0); + if (IS_ERR(clk)) { + pr_err("Can't get timer clock.\n"); + return; + } + + nps_setup_clocksource(node, clk); +} + +CLOCKSOURCE_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer", + nps_timer_init); |