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authorLinus Torvalds <torvalds@linux-foundation.org>2016-05-19 12:46:18 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2016-05-19 12:46:18 -0400
commit0efacbbaee1e94e9942da0912f5b46ffd45a74bd (patch)
treea17933437de955f4ce5e74760610bab75f2ae385 /drivers/clocksource/timer-nps.c
parentf4f27d0028aabce57e44c16c2fdefccd6310d2f3 (diff)
parent776d7f1694a7d678291354a05f0243965708306a (diff)
Merge tag 'arc-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta: "We have a relatively big changeset for ARC for 4.7. The highlight is support for EZChip (now Mellanox) NPS-400 network processor, a 400-Gb throughput C-programmable packet processor based on ARC700 cores from Synopsys. See http://www.mellanox.com/related-docs/prod_npu/PB_NPS-400.pdf Also present are irqchip and clocksource drivers for NPS as agreed with respective maintainers to go via ARC tree due to an soc header dependency. I have the needed ACKs from Jason, Marc, Daniel. You might run into a trivial merge conflict in drivers/irqchip/* This EZChip platform support required some deep changes in ARC architecture code and also opportunity to cleanup past sins (legacy irq domains, missing irq domain lookup, hard coded timer irqs...) Summary: - Support for EZChip (now Mellanox) NPS-400 Network processor based on ARC700 - NPS interrupt controller and clocksource drivers - ARC timers probed off DT - ARC iqrchips switching to linear domain (upgrade from legacy domains)" * tag 'arc-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (37 commits) arc: axs103_smp: Fix CPU frequency to 100MHz for dual-core arc: axs10x: Add DT bindings for I2S PLL Clock ARC: pae: STRICT_MM_TYPECHECKS was broken ARC: Add eznps platform to Kconfig and Makefile ARC: [plat-eznps] Use dedicated COMMAND_LINE_SIZE ARC: [plat-eznps] Use dedicated cpu_relax() ARC: [plat-eznps] Use dedicated identity auxiliary register. ARC: [plat-eznps] Use dedicated SMP barriers ARC: [plat-eznps] Use dedicated atomic/bitops/cmpxchg ARC: [plat-eznps] Use dedicated user stack top ARC: [plat-eznps] Add eznps platform ARC: [plat-eznps] Add eznps board defconfig and dts ARC: Mark secondary cpu online only after all HW setup is done ARC: rwlock: disable interrupts in !LLSC variant ARC: Make vmalloc size configurable ARC: clean out UAPI byteorder.h clean off Kconfig symbol irqchip: add nps Internal and external irqchips clocksource: Add NPS400 timers driver soc: Support for EZchip SoC Documentation: Add EZchip vendor to binding list ...
Diffstat (limited to 'drivers/clocksource/timer-nps.c')
-rw-r--r--drivers/clocksource/timer-nps.c98
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 000000000000..d46108920b2c
--- /dev/null
+++ b/drivers/clocksource/timer-nps.c
@@ -0,0 +1,98 @@
1/*
2 * Copyright (c) 2016, Mellanox Technologies. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#include <linux/interrupt.h>
34#include <linux/clocksource.h>
35#include <linux/clockchips.h>
36#include <linux/clk.h>
37#include <linux/of.h>
38#include <linux/of_irq.h>
39#include <linux/cpu.h>
40#include <soc/nps/common.h>
41
42#define NPS_MSU_TICK_LOW 0xC8
43#define NPS_CLUSTER_OFFSET 8
44#define NPS_CLUSTER_NUM 16
45
46/* This array is per cluster of CPUs (Each NPS400 cluster got 256 CPUs) */
47static void *nps_msu_reg_low_addr[NPS_CLUSTER_NUM] __read_mostly;
48
49static unsigned long nps_timer_rate;
50
51static cycle_t nps_clksrc_read(struct clocksource *clksrc)
52{
53 int cluster = raw_smp_processor_id() >> NPS_CLUSTER_OFFSET;
54
55 return (cycle_t)ioread32be(nps_msu_reg_low_addr[cluster]);
56}
57
58static void __init nps_setup_clocksource(struct device_node *node,
59 struct clk *clk)
60{
61 int ret, cluster;
62
63 for (cluster = 0; cluster < NPS_CLUSTER_NUM; cluster++)
64 nps_msu_reg_low_addr[cluster] =
65 nps_host_reg((cluster << NPS_CLUSTER_OFFSET),
66 NPS_MSU_BLKID, NPS_MSU_TICK_LOW);
67
68 ret = clk_prepare_enable(clk);
69 if (ret) {
70 pr_err("Couldn't enable parent clock\n");
71 return;
72 }
73
74 nps_timer_rate = clk_get_rate(clk);
75
76 ret = clocksource_mmio_init(nps_msu_reg_low_addr, "EZnps-tick",
77 nps_timer_rate, 301, 32, nps_clksrc_read);
78 if (ret) {
79 pr_err("Couldn't register clock source.\n");
80 clk_disable_unprepare(clk);
81 }
82}
83
84static void __init nps_timer_init(struct device_node *node)
85{
86 struct clk *clk;
87
88 clk = of_clk_get(node, 0);
89 if (IS_ERR(clk)) {
90 pr_err("Can't get timer clock.\n");
91 return;
92 }
93
94 nps_setup_clocksource(node, clk);
95}
96
97CLOCKSOURCE_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer",
98 nps_timer_init);