diff mbox

[v3,1/2] clocksource: Add Oxford Semiconductor RPS Dual Timer

Message ID 1465985607-21231-2-git-send-email-narmstrong@baylibre.com (mailing list archive)
State New, archived
Headers show

Commit Message

Neil Armstrong June 15, 2016, 10:13 a.m. UTC
Add clocksource and clockevent driver from dual RPS timer.
The HW provides a dual one-shot or periodic 24bit timers,
the drivers set the first one as tick event source and the
second as a continuous scheduler clock source.
The timer can use 1, 16 or 256 as pre-dividers, thus the
clocksource uses 16 by default.

CC: Ma Haijun <mahaijuns@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/clocksource/Kconfig           |   7 +
 drivers/clocksource/Makefile          |   1 +
 drivers/clocksource/timer-oxnas-rps.c | 290 ++++++++++++++++++++++++++++++++++
 3 files changed, 298 insertions(+)
 create mode 100644 drivers/clocksource/timer-oxnas-rps.c

Comments

kernel test robot June 15, 2016, 3:35 p.m. UTC | #1
Hi,

[auto build test WARNING on tip/timers/core]
[also build test WARNING on v4.7-rc3 next-20160615]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Neil-Armstrong/clocksource-Add-support-for-Oxford-Semiconductor-RPS-Dual-Timer/20160615-181650
config: blackfin-allmodconfig (attached as .config)
compiler: bfin-uclinux-gcc (GCC) 4.6.3
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=blackfin 

All warnings (new ones prefixed by >>):

>> drivers/clocksource/timer-oxnas-rps.c:50:0: warning: "TIMER_ENABLE" redefined [enabled by default]
   arch/blackfin/mach-bf533/include/mach/defBF532.h:97:0: note: this is the location of the previous definition

vim +/TIMER_ENABLE +50 drivers/clocksource/timer-oxnas-rps.c

    34	/* TIMER1 used as tick
    35	 * TIMER2 used as clocksource
    36	 */
    37	
    38	/* Registers definitions */
    39	
    40	#define TIMER_LOAD_REG		0x0
    41	#define TIMER_CURR_REG		0x4
    42	#define TIMER_CTRL_REG		0x8
    43	#define TIMER_CLRINT_REG	0xC
    44	
    45	#define TIMER_BITS		24
    46	
    47	#define TIMER_MAX_VAL		(BIT(TIMER_BITS) - 1)
    48	
    49	#define TIMER_PERIODIC		BIT(6)
  > 50	#define TIMER_ENABLE		BIT(7)
    51	
    52	#define TIMER_DIV1		(0)
    53	#define TIMER_DIV16		(1 << 2)
    54	#define TIMER_DIV256		(2 << 2)
    55	
    56	#define TIMER1_REG_OFFSET	0
    57	#define TIMER2_REG_OFFSET	0x20
    58	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
kernel test robot June 15, 2016, 3:51 p.m. UTC | #2
Hi,

[auto build test ERROR on tip/timers/core]
[also build test ERROR on v4.7-rc3 next-20160615]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Neil-Armstrong/clocksource-Add-support-for-Oxford-Semiconductor-RPS-Dual-Timer/20160615-181650
config: ia64-allyesconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 4.9.0
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=ia64 

All error/warnings (new ones prefixed by >>):

>> drivers/clocksource/timer-oxnas-rps.c:62:28: error: field 'clkevent' has incomplete type
     struct clock_event_device clkevent;
                               ^
   In file included from include/linux/list.h:8:0,
                    from include/linux/smp.h:11,
                    from include/linux/irq.h:12,
                    from drivers/clocksource/timer-oxnas-rps.c:24:
   drivers/clocksource/timer-oxnas-rps.c: In function 'oxnas_rps_timer_shutdown':
   include/linux/kernel.h:831:48: warning: initialization from incompatible pointer type
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
>> drivers/clocksource/timer-oxnas-rps.c:101:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   include/linux/kernel.h:831:48: warning: (near initialization for 'rps')
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
>> drivers/clocksource/timer-oxnas-rps.c:101:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   drivers/clocksource/timer-oxnas-rps.c: In function 'oxnas_rps_timer_set_periodic':
   include/linux/kernel.h:831:48: warning: initialization from incompatible pointer type
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
   drivers/clocksource/timer-oxnas-rps.c:111:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   include/linux/kernel.h:831:48: warning: (near initialization for 'rps')
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
   drivers/clocksource/timer-oxnas-rps.c:111:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   drivers/clocksource/timer-oxnas-rps.c: In function 'oxnas_rps_timer_set_oneshot':
   include/linux/kernel.h:831:48: warning: initialization from incompatible pointer type
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
   drivers/clocksource/timer-oxnas-rps.c:121:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   include/linux/kernel.h:831:48: warning: (near initialization for 'rps')
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
   drivers/clocksource/timer-oxnas-rps.c:121:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   drivers/clocksource/timer-oxnas-rps.c: In function 'oxnas_rps_timer_next_event':
   include/linux/kernel.h:831:48: warning: initialization from incompatible pointer type
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
   drivers/clocksource/timer-oxnas-rps.c:132:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   include/linux/kernel.h:831:48: warning: (near initialization for 'rps')
     const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                   ^
   drivers/clocksource/timer-oxnas-rps.c:132:3: note: in expansion of macro 'container_of'
      container_of(evt, struct oxnas_rps_timer, clkevent);
      ^
   drivers/clocksource/timer-oxnas-rps.c: In function 'oxnas_rps_clockevent_init':
>> drivers/clocksource/timer-oxnas-rps.c:161:27: error: 'CLOCK_EVT_FEAT_PERIODIC' undeclared (first use in this function)
     rps->clkevent.features = CLOCK_EVT_FEAT_PERIODIC |
                              ^
   drivers/clocksource/timer-oxnas-rps.c:161:27: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/clocksource/timer-oxnas-rps.c:162:6: error: 'CLOCK_EVT_FEAT_ONESHOT' undeclared (first use in this function)
         CLOCK_EVT_FEAT_ONESHOT |
         ^
>> drivers/clocksource/timer-oxnas-rps.c:163:6: error: 'CLOCK_EVT_FEAT_DYNIRQ' undeclared (first use in this function)
         CLOCK_EVT_FEAT_DYNIRQ;
         ^
>> drivers/clocksource/timer-oxnas-rps.c:172:2: error: implicit declaration of function 'clockevents_config_and_register' [-Werror=implicit-function-declaration]
     clockevents_config_and_register(&rps->clkevent,
     ^
   drivers/clocksource/timer-oxnas-rps.c: In function 'oxnas_rps_clocksource_init':
>> drivers/clocksource/timer-oxnas-rps.c:209:2: error: implicit declaration of function 'clocksource_mmio_init' [-Werror=implicit-function-declaration]
     ret = clocksource_mmio_init(timer_sched_base,
     ^
>> drivers/clocksource/timer-oxnas-rps.c:212:9: error: 'clocksource_mmio_readl_down' undeclared (first use in this function)
            clocksource_mmio_readl_down);
            ^
   drivers/clocksource/timer-oxnas-rps.c: At top level:
>> drivers/clocksource/timer-oxnas-rps.c:290:10: error: expected ')' before string constant
             "oxsemi,ox810se-rps-timer", oxnas_rps_timer_init);
             ^
   drivers/clocksource/timer-oxnas-rps.c:223:20: warning: 'oxnas_rps_timer_init' defined but not used [-Wunused-function]
    static void __init oxnas_rps_timer_init(struct device_node *np)
                       ^
   cc1: some warnings being treated as errors

vim +/clkevent +62 drivers/clocksource/timer-oxnas-rps.c

    18	 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    19	 */
    20	
    21	#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
    22	
    23	#include <linux/init.h>
  > 24	#include <linux/irq.h>
    25	#include <linux/io.h>
    26	#include <linux/clk.h>
    27	#include <linux/slab.h>
    28	#include <linux/interrupt.h>
    29	#include <linux/of_irq.h>
    30	#include <linux/of_address.h>
    31	#include <linux/clockchips.h>
    32	#include <linux/sched_clock.h>
    33	
    34	/* TIMER1 used as tick
    35	 * TIMER2 used as clocksource
    36	 */
    37	
    38	/* Registers definitions */
    39	
    40	#define TIMER_LOAD_REG		0x0
    41	#define TIMER_CURR_REG		0x4
    42	#define TIMER_CTRL_REG		0x8
    43	#define TIMER_CLRINT_REG	0xC
    44	
    45	#define TIMER_BITS		24
    46	
    47	#define TIMER_MAX_VAL		(BIT(TIMER_BITS) - 1)
    48	
    49	#define TIMER_PERIODIC		BIT(6)
    50	#define TIMER_ENABLE		BIT(7)
    51	
    52	#define TIMER_DIV1		(0)
    53	#define TIMER_DIV16		(1 << 2)
    54	#define TIMER_DIV256		(2 << 2)
    55	
    56	#define TIMER1_REG_OFFSET	0
    57	#define TIMER2_REG_OFFSET	0x20
    58	
    59	/* Clockevent & Clocksource data */
    60	
    61	struct oxnas_rps_timer {
  > 62		struct clock_event_device clkevent;
    63		void __iomem *clksrc_base;
    64		void __iomem *clkevt_base;
    65		unsigned long timer_period;
    66		unsigned int timer_prescaler;
    67		struct clk *clk;
    68		int irq;
    69	};
    70	
    71	static irqreturn_t oxnas_rps_timer_irq(int irq, void *dev_id)
    72	{
    73		struct oxnas_rps_timer *rps = dev_id;
    74	
    75		writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
    76	
    77		rps->clkevent.event_handler(&rps->clkevent);
    78	
    79		return IRQ_HANDLED;
    80	}
    81	
    82	static void oxnas_rps_timer_config(struct oxnas_rps_timer *rps,
    83					   unsigned long period,
    84					   unsigned int periodic)
    85	{
    86		uint32_t cfg = rps->timer_prescaler;
    87	
    88		if (period)
    89			cfg |= TIMER_ENABLE;
    90	
    91		if (periodic)
    92			cfg |= TIMER_PERIODIC;
    93	
    94		writel_relaxed(period, rps->clkevt_base + TIMER_LOAD_REG);
    95		writel_relaxed(cfg, rps->clkevt_base + TIMER_CTRL_REG);
    96	}
    97	
    98	static int oxnas_rps_timer_shutdown(struct clock_event_device *evt)
    99	{
   100		struct oxnas_rps_timer *rps =
 > 101			container_of(evt, struct oxnas_rps_timer, clkevent);
   102	
   103		oxnas_rps_timer_config(rps, 0, 0);
   104	
   105		return 0;
   106	}
   107	
   108	static int oxnas_rps_timer_set_periodic(struct clock_event_device *evt)
   109	{
   110		struct oxnas_rps_timer *rps =
   111			container_of(evt, struct oxnas_rps_timer, clkevent);
   112	
   113		oxnas_rps_timer_config(rps, rps->timer_period, 1);
   114	
   115		return 0;
   116	}
   117	
   118	static int oxnas_rps_timer_set_oneshot(struct clock_event_device *evt)
   119	{
   120		struct oxnas_rps_timer *rps =
   121			container_of(evt, struct oxnas_rps_timer, clkevent);
   122	
   123		oxnas_rps_timer_config(rps, rps->timer_period, 0);
   124	
   125		return 0;
   126	}
   127	
   128	static int oxnas_rps_timer_next_event(unsigned long delta,
   129					struct clock_event_device *evt)
   130	{
   131		struct oxnas_rps_timer *rps =
 > 132			container_of(evt, struct oxnas_rps_timer, clkevent);
   133	
   134		oxnas_rps_timer_config(rps, delta, 0);
   135	
   136		return 0;
   137	}
   138	
   139	static int __init oxnas_rps_clockevent_init(struct oxnas_rps_timer *rps)
   140	{
   141		ulong clk_rate = clk_get_rate(rps->clk);
   142		ulong timer_rate;
   143	
   144		/* Start with prescaler 1 */
   145		rps->timer_prescaler = TIMER_DIV1;
   146		rps->timer_period = DIV_ROUND_UP(clk_rate, HZ);
   147		timer_rate = clk_rate;
   148	
   149		if (rps->timer_period > TIMER_MAX_VAL) {
   150			rps->timer_prescaler = TIMER_DIV16;
   151			timer_rate = clk_rate / 16;
   152			rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
   153		}
   154		if (rps->timer_period > TIMER_MAX_VAL) {
   155			rps->timer_prescaler = TIMER_DIV256;
   156			timer_rate = clk_rate / 256;
   157			rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
   158		}
   159	
   160		rps->clkevent.name = "oxnas-rps";
 > 161		rps->clkevent.features = CLOCK_EVT_FEAT_PERIODIC |
 > 162					 CLOCK_EVT_FEAT_ONESHOT |
 > 163					 CLOCK_EVT_FEAT_DYNIRQ;
   164		rps->clkevent.tick_resume = oxnas_rps_timer_shutdown;
   165		rps->clkevent.set_state_shutdown = oxnas_rps_timer_shutdown;
   166		rps->clkevent.set_state_periodic = oxnas_rps_timer_set_periodic;
   167		rps->clkevent.set_state_oneshot = oxnas_rps_timer_set_oneshot;
   168		rps->clkevent.set_next_event = oxnas_rps_timer_next_event;
   169		rps->clkevent.rating = 200;
   170		rps->clkevent.cpumask = cpu_possible_mask;
   171		rps->clkevent.irq = rps->irq;
 > 172		clockevents_config_and_register(&rps->clkevent,
   173						timer_rate,
   174						1,
   175						TIMER_MAX_VAL);
   176	
   177		pr_info("Registered clock event rate %luHz prescaler %x period %lu\n",
   178				clk_rate,
   179				rps->timer_prescaler,
   180				rps->timer_period);
   181	
   182		return 0;
   183	}
   184	
   185	/* Clocksource */
   186	
   187	static void __iomem *timer_sched_base;
   188	
   189	static u64 notrace oxnas_rps_read_sched_clock(void)
   190	{
   191		return ~readl_relaxed(timer_sched_base);
   192	}
   193	
   194	static int __init oxnas_rps_clocksource_init(struct oxnas_rps_timer *rps)
   195	{
   196		ulong clk_rate = clk_get_rate(rps->clk);
   197		int ret;
   198	
   199		/* use prescale 16 */
   200		clk_rate = clk_rate / 16;
   201	
   202		writel_relaxed(TIMER_MAX_VAL, rps->clksrc_base + TIMER_LOAD_REG);
   203		writel_relaxed(TIMER_PERIODIC | TIMER_ENABLE | TIMER_DIV16,
   204				rps->clksrc_base + TIMER_CTRL_REG);
   205	
   206		timer_sched_base = rps->clksrc_base + TIMER_CURR_REG;
   207		sched_clock_register(oxnas_rps_read_sched_clock,
   208				     TIMER_BITS, clk_rate);
 > 209		ret = clocksource_mmio_init(timer_sched_base,
   210					    "oxnas_rps_clocksource_timer",
   211					    clk_rate, 250, TIMER_BITS,
 > 212					    clocksource_mmio_readl_down);
   213		if (WARN_ON(ret)) {
   214			pr_err("can't register clocksource\n");
   215			return ret;

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Daniel Lezcano June 16, 2016, 1:29 p.m. UTC | #3
On 06/15/2016 05:51 PM, kbuild test robot wrote:
> Hi,
>
> [auto build test ERROR on tip/timers/core]
> [also build test ERROR on v4.7-rc3 next-20160615]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

You should add in the Kconfig:

+depends on GENERIC_CLOCKSOURCE
Daniel Lezcano June 16, 2016, 1:33 p.m. UTC | #4
On 06/15/2016 05:35 PM, kbuild test robot wrote:
> Hi,
>
> [auto build test WARNING on tip/timers/core]
> [also build test WARNING on v4.7-rc3 next-20160615]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url:    https://github.com/0day-ci/linux/commits/Neil-Armstrong/clocksource-Add-support-for-Oxford-Semiconductor-RPS-Dual-Timer/20160615-181650
> config: blackfin-allmodconfig (attached as .config)
> compiler: bfin-uclinux-gcc (GCC) 4.6.3
> reproduce:
>          wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
>          chmod +x ~/bin/make.cross
>          # save the attached .config to linux build tree
>          make.cross ARCH=blackfin
>
> All warnings (new ones prefixed by >>):
>
>>> drivers/clocksource/timer-oxnas-rps.c:50:0: warning: "TIMER_ENABLE" redefined [enabled by default]
>     arch/blackfin/mach-bf533/include/mach/defBF532.h:97:0: note: this is the location of the previous definition
>
> vim +/TIMER_ENABLE +50 drivers/clocksource/timer-oxnas-rps.c
>
>      34	/* TIMER1 used as tick
>      35	 * TIMER2 used as clocksource
>      36	 */
>      37	
>      38	/* Registers definitions */
>      39	
>      40	#define TIMER_LOAD_REG		0x0
>      41	#define TIMER_CURR_REG		0x4
>      42	#define TIMER_CTRL_REG		0x8
>      43	#define TIMER_CLRINT_REG	0xC
>      44	
>      45	#define TIMER_BITS		24
>      46	
>      47	#define TIMER_MAX_VAL		(BIT(TIMER_BITS) - 1)
>      48	
>      49	#define TIMER_PERIODIC		BIT(6)
>    > 50	#define TIMER_ENABLE		BIT(7)

It is already defined in the arch/blackfin/include dir.
Neil Armstrong June 16, 2016, 1:47 p.m. UTC | #5
On 06/16/2016 03:33 PM, Daniel Lezcano wrote:
> On 06/15/2016 05:35 PM, kbuild test robot wrote:
>> Hi,
>>
>> [auto build test WARNING on tip/timers/core]
>> [also build test WARNING on v4.7-rc3 next-20160615]
>> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>>
>> url:    https://github.com/0day-ci/linux/commits/Neil-Armstrong/clocksource-Add-support-for-Oxford-Semiconductor-RPS-Dual-Timer/20160615-181650
>> config: blackfin-allmodconfig (attached as .config)
>> compiler: bfin-uclinux-gcc (GCC) 4.6.3
>> reproduce:
>>          wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
>>          chmod +x ~/bin/make.cross
>>          # save the attached .config to linux build tree
>>          make.cross ARCH=blackfin
>>
>> All warnings (new ones prefixed by >>):
>>
>>>> drivers/clocksource/timer-oxnas-rps.c:50:0: warning: "TIMER_ENABLE" redefined [enabled by default]
>>     arch/blackfin/mach-bf533/include/mach/defBF532.h:97:0: note: this is the location of the previous definition
>>
>> vim +/TIMER_ENABLE +50 drivers/clocksource/timer-oxnas-rps.c
>>
>>      34    /* TIMER1 used as tick
>>      35     * TIMER2 used as clocksource
>>      36     */
>>      37   
>>      38    /* Registers definitions */
>>      39   
>>      40    #define TIMER_LOAD_REG        0x0
>>      41    #define TIMER_CURR_REG        0x4
>>      42    #define TIMER_CTRL_REG        0x8
>>      43    #define TIMER_CLRINT_REG    0xC
>>      44   
>>      45    #define TIMER_BITS        24
>>      46   
>>      47    #define TIMER_MAX_VAL        (BIT(TIMER_BITS) - 1)
>>      48   
>>      49    #define TIMER_PERIODIC        BIT(6)
>>    > 50    #define TIMER_ENABLE        BIT(7)
> 
> It is already defined in the arch/blackfin/include dir.
> 

Hi Daniel,

This should never happen due to the blackfin headers.
Actually the COMPILE_TEST option made these two happen.

Should I push a v4 to keep COMPILE_TEST ?

Neil
Daniel Lezcano June 16, 2016, 2:14 p.m. UTC | #6
On 06/16/2016 03:47 PM, Neil Armstrong wrote:
> On 06/16/2016 03:33 PM, Daniel Lezcano wrote:
>> On 06/15/2016 05:35 PM, kbuild test robot wrote:
>>> Hi,
>>>
>>> [auto build test WARNING on tip/timers/core]
>>> [also build test WARNING on v4.7-rc3 next-20160615]
>>> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>>>
>>> url:    https://github.com/0day-ci/linux/commits/Neil-Armstrong/clocksource-Add-support-for-Oxford-Semiconductor-RPS-Dual-Timer/20160615-181650
>>> config: blackfin-allmodconfig (attached as .config)
>>> compiler: bfin-uclinux-gcc (GCC) 4.6.3
>>> reproduce:
>>>           wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
>>>           chmod +x ~/bin/make.cross
>>>           # save the attached .config to linux build tree
>>>           make.cross ARCH=blackfin
>>>
>>> All warnings (new ones prefixed by >>):
>>>
>>>>> drivers/clocksource/timer-oxnas-rps.c:50:0: warning: "TIMER_ENABLE" redefined [enabled by default]
>>>      arch/blackfin/mach-bf533/include/mach/defBF532.h:97:0: note: this is the location of the previous definition
>>>
>>> vim +/TIMER_ENABLE +50 drivers/clocksource/timer-oxnas-rps.c
>>>
>>>       34    /* TIMER1 used as tick
>>>       35     * TIMER2 used as clocksource
>>>       36     */
>>>       37
>>>       38    /* Registers definitions */
>>>       39
>>>       40    #define TIMER_LOAD_REG        0x0
>>>       41    #define TIMER_CURR_REG        0x4
>>>       42    #define TIMER_CTRL_REG        0x8
>>>       43    #define TIMER_CLRINT_REG    0xC
>>>       44
>>>       45    #define TIMER_BITS        24
>>>       46
>>>       47    #define TIMER_MAX_VAL        (BIT(TIMER_BITS) - 1)
>>>       48
>>>       49    #define TIMER_PERIODIC        BIT(6)
>>>     > 50    #define TIMER_ENABLE        BIT(7)
>>
>> It is already defined in the arch/blackfin/include dir.
>>
>
> Hi Daniel,
>
> This should never happen due to the blackfin headers.
> Actually the COMPILE_TEST option made these two happen.
>
> Should I push a v4 to keep COMPILE_TEST ?

The easier way would be:
	depends on !BLACKFIN

I will take care of cleaning up this macro name collision when moving 
the timer driver in drivers/clocksource (that's really in the future ...).

The idea is to have all the drivers with the COMPILE_TEST option set, so 
we can spot more issues at compile time earlier. This change reveals, of 
course, some errors we were not facing before and at least it has the 
benefit to enlighten some arch-shadowed drivers.

   -- Daniel
Daniel Lezcano June 16, 2016, 2:15 p.m. UTC | #7
On 06/16/2016 03:47 PM, Neil Armstrong wrote:
> On 06/16/2016 03:33 PM, Daniel Lezcano wrote:
>> On 06/15/2016 05:35 PM, kbuild test robot wrote:
>>> Hi,
>>>
>>> [auto build test WARNING on tip/timers/core]
>>> [also build test WARNING on v4.7-rc3 next-20160615]
>>> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>>>
>>> url:    https://github.com/0day-ci/linux/commits/Neil-Armstrong/clocksource-Add-support-for-Oxford-Semiconductor-RPS-Dual-Timer/20160615-181650
>>> config: blackfin-allmodconfig (attached as .config)
>>> compiler: bfin-uclinux-gcc (GCC) 4.6.3
>>> reproduce:
>>>           wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
>>>           chmod +x ~/bin/make.cross
>>>           # save the attached .config to linux build tree
>>>           make.cross ARCH=blackfin
>>>
>>> All warnings (new ones prefixed by >>):
>>>
>>>>> drivers/clocksource/timer-oxnas-rps.c:50:0: warning: "TIMER_ENABLE" redefined [enabled by default]
>>>      arch/blackfin/mach-bf533/include/mach/defBF532.h:97:0: note: this is the location of the previous definition
>>>
>>> vim +/TIMER_ENABLE +50 drivers/clocksource/timer-oxnas-rps.c
>>>
>>>       34    /* TIMER1 used as tick
>>>       35     * TIMER2 used as clocksource
>>>       36     */
>>>       37
>>>       38    /* Registers definitions */
>>>       39
>>>       40    #define TIMER_LOAD_REG        0x0
>>>       41    #define TIMER_CURR_REG        0x4
>>>       42    #define TIMER_CTRL_REG        0x8
>>>       43    #define TIMER_CLRINT_REG    0xC
>>>       44
>>>       45    #define TIMER_BITS        24
>>>       46
>>>       47    #define TIMER_MAX_VAL        (BIT(TIMER_BITS) - 1)
>>>       48
>>>       49    #define TIMER_PERIODIC        BIT(6)
>>>     > 50    #define TIMER_ENABLE        BIT(7)
>>
>> It is already defined in the arch/blackfin/include dir.
>>
>
> Hi Daniel,
>
> This should never happen due to the blackfin headers.
> Actually the COMPILE_TEST option made these two happen.
>
> Should I push a v4 to keep COMPILE_TEST ?

Oh, actually with 'depends on GENERIC_CLOCKSOURCE', that should solve 
both errors.
diff mbox

Patch

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 47352d2..7e937e1 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -293,6 +293,13 @@  config VF_PIT_TIMER
 	help
 	  Support for Period Interrupt Timer on Freescale Vybrid Family SoCs.
 
+config OXNAS_RPS_TIMER
+	bool "Oxford Semiconductor OXNAS RPS Timers driver" if COMPILE_TEST
+	select CLKSRC_OF
+	select CLKSRC_MMIO
+	help
+	  This enables support for the Oxford Semiconductor OXNAS RPS timers.
+
 config SYS_SUPPORTS_SH_CMT
         bool
 
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 473974f..bc66981 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -48,6 +48,7 @@  obj-$(CONFIG_MTK_TIMER)		+= mtk_timer.o
 obj-$(CONFIG_CLKSRC_PISTACHIO)	+= time-pistachio.o
 obj-$(CONFIG_CLKSRC_TI_32K)	+= timer-ti-32k.o
 obj-$(CONFIG_CLKSRC_NPS)	+= timer-nps.o
+obj-$(CONFIG_OXNAS_RPS_TIMER)	+= timer-oxnas-rps.o
 
 obj-$(CONFIG_ARM_ARCH_TIMER)		+= arm_arch_timer.o
 obj-$(CONFIG_ARM_GLOBAL_TIMER)		+= arm_global_timer.o
diff --git a/drivers/clocksource/timer-oxnas-rps.c b/drivers/clocksource/timer-oxnas-rps.c
new file mode 100644
index 0000000..c002e99
--- /dev/null
+++ b/drivers/clocksource/timer-oxnas-rps.c
@@ -0,0 +1,290 @@ 
+/*
+ * drivers/clocksource/timer-oxnas-rps.c
+ *
+ * Copyright (C) 2009 Oxford Semiconductor Ltd
+ * Copyright (C) 2013 Ma Haijun <mahaijuns@gmail.com>
+ * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/clockchips.h>
+#include <linux/sched_clock.h>
+
+/* TIMER1 used as tick
+ * TIMER2 used as clocksource
+ */
+
+/* Registers definitions */
+
+#define TIMER_LOAD_REG		0x0
+#define TIMER_CURR_REG		0x4
+#define TIMER_CTRL_REG		0x8
+#define TIMER_CLRINT_REG	0xC
+
+#define TIMER_BITS		24
+
+#define TIMER_MAX_VAL		(BIT(TIMER_BITS) - 1)
+
+#define TIMER_PERIODIC		BIT(6)
+#define TIMER_ENABLE		BIT(7)
+
+#define TIMER_DIV1		(0)
+#define TIMER_DIV16		(1 << 2)
+#define TIMER_DIV256		(2 << 2)
+
+#define TIMER1_REG_OFFSET	0
+#define TIMER2_REG_OFFSET	0x20
+
+/* Clockevent & Clocksource data */
+
+struct oxnas_rps_timer {
+	struct clock_event_device clkevent;
+	void __iomem *clksrc_base;
+	void __iomem *clkevt_base;
+	unsigned long timer_period;
+	unsigned int timer_prescaler;
+	struct clk *clk;
+	int irq;
+};
+
+static irqreturn_t oxnas_rps_timer_irq(int irq, void *dev_id)
+{
+	struct oxnas_rps_timer *rps = dev_id;
+
+	writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
+
+	rps->clkevent.event_handler(&rps->clkevent);
+
+	return IRQ_HANDLED;
+}
+
+static void oxnas_rps_timer_config(struct oxnas_rps_timer *rps,
+				   unsigned long period,
+				   unsigned int periodic)
+{
+	uint32_t cfg = rps->timer_prescaler;
+
+	if (period)
+		cfg |= TIMER_ENABLE;
+
+	if (periodic)
+		cfg |= TIMER_PERIODIC;
+
+	writel_relaxed(period, rps->clkevt_base + TIMER_LOAD_REG);
+	writel_relaxed(cfg, rps->clkevt_base + TIMER_CTRL_REG);
+}
+
+static int oxnas_rps_timer_shutdown(struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, 0, 0);
+
+	return 0;
+}
+
+static int oxnas_rps_timer_set_periodic(struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, rps->timer_period, 1);
+
+	return 0;
+}
+
+static int oxnas_rps_timer_set_oneshot(struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, rps->timer_period, 0);
+
+	return 0;
+}
+
+static int oxnas_rps_timer_next_event(unsigned long delta,
+				struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, delta, 0);
+
+	return 0;
+}
+
+static int __init oxnas_rps_clockevent_init(struct oxnas_rps_timer *rps)
+{
+	ulong clk_rate = clk_get_rate(rps->clk);
+	ulong timer_rate;
+
+	/* Start with prescaler 1 */
+	rps->timer_prescaler = TIMER_DIV1;
+	rps->timer_period = DIV_ROUND_UP(clk_rate, HZ);
+	timer_rate = clk_rate;
+
+	if (rps->timer_period > TIMER_MAX_VAL) {
+		rps->timer_prescaler = TIMER_DIV16;
+		timer_rate = clk_rate / 16;
+		rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
+	}
+	if (rps->timer_period > TIMER_MAX_VAL) {
+		rps->timer_prescaler = TIMER_DIV256;
+		timer_rate = clk_rate / 256;
+		rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
+	}
+
+	rps->clkevent.name = "oxnas-rps";
+	rps->clkevent.features = CLOCK_EVT_FEAT_PERIODIC |
+				 CLOCK_EVT_FEAT_ONESHOT |
+				 CLOCK_EVT_FEAT_DYNIRQ;
+	rps->clkevent.tick_resume = oxnas_rps_timer_shutdown;
+	rps->clkevent.set_state_shutdown = oxnas_rps_timer_shutdown;
+	rps->clkevent.set_state_periodic = oxnas_rps_timer_set_periodic;
+	rps->clkevent.set_state_oneshot = oxnas_rps_timer_set_oneshot;
+	rps->clkevent.set_next_event = oxnas_rps_timer_next_event;
+	rps->clkevent.rating = 200;
+	rps->clkevent.cpumask = cpu_possible_mask;
+	rps->clkevent.irq = rps->irq;
+	clockevents_config_and_register(&rps->clkevent,
+					timer_rate,
+					1,
+					TIMER_MAX_VAL);
+
+	pr_info("Registered clock event rate %luHz prescaler %x period %lu\n",
+			clk_rate,
+			rps->timer_prescaler,
+			rps->timer_period);
+
+	return 0;
+}
+
+/* Clocksource */
+
+static void __iomem *timer_sched_base;
+
+static u64 notrace oxnas_rps_read_sched_clock(void)
+{
+	return ~readl_relaxed(timer_sched_base);
+}
+
+static int __init oxnas_rps_clocksource_init(struct oxnas_rps_timer *rps)
+{
+	ulong clk_rate = clk_get_rate(rps->clk);
+	int ret;
+
+	/* use prescale 16 */
+	clk_rate = clk_rate / 16;
+
+	writel_relaxed(TIMER_MAX_VAL, rps->clksrc_base + TIMER_LOAD_REG);
+	writel_relaxed(TIMER_PERIODIC | TIMER_ENABLE | TIMER_DIV16,
+			rps->clksrc_base + TIMER_CTRL_REG);
+
+	timer_sched_base = rps->clksrc_base + TIMER_CURR_REG;
+	sched_clock_register(oxnas_rps_read_sched_clock,
+			     TIMER_BITS, clk_rate);
+	ret = clocksource_mmio_init(timer_sched_base,
+				    "oxnas_rps_clocksource_timer",
+				    clk_rate, 250, TIMER_BITS,
+				    clocksource_mmio_readl_down);
+	if (WARN_ON(ret)) {
+		pr_err("can't register clocksource\n");
+		return ret;
+	}
+
+	pr_info("Registered clocksource rate %luHz\n", clk_rate);
+
+	return 0;
+}
+
+static void __init oxnas_rps_timer_init(struct device_node *np)
+{
+	struct oxnas_rps_timer *rps;
+	void __iomem *base;
+	int ret;
+
+	rps = kzalloc(sizeof(*rps), GFP_KERNEL);
+	if (!rps) {
+		pr_err("Failed to allocate rps structure\n");
+		return;
+	}
+
+	rps->clk = of_clk_get(np, 0);
+	if (WARN_ON(IS_ERR(rps->clk)))
+		goto err_alloc;
+
+	if (WARN_ON(clk_prepare_enable(rps->clk)))
+		goto err_clk;
+
+	base = of_iomap(np, 0);
+	if (WARN_ON(!base))
+		goto err_clk_prepare;
+
+	rps->irq = irq_of_parse_and_map(np, 0);
+	if (WARN_ON(rps->irq < 0))
+		goto err_iomap;
+
+	rps->clkevt_base = base + TIMER1_REG_OFFSET;
+	rps->clksrc_base = base + TIMER2_REG_OFFSET;
+
+	/* Disable timers */
+	writel_relaxed(0, rps->clkevt_base + TIMER_CTRL_REG);
+	writel_relaxed(0, rps->clksrc_base + TIMER_CTRL_REG);
+	writel_relaxed(0, rps->clkevt_base + TIMER_LOAD_REG);
+	writel_relaxed(0, rps->clksrc_base + TIMER_LOAD_REG);
+	writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
+	writel_relaxed(0, rps->clksrc_base + TIMER_CLRINT_REG);
+
+	ret = request_irq(rps->irq, oxnas_rps_timer_irq,
+			  IRQF_TIMER | IRQF_IRQPOLL,
+			  "rps-timer", rps);
+	if (WARN_ON(ret))
+		goto err_iomap;
+
+	ret = oxnas_rps_clocksource_init(rps);
+	if (ret)
+		goto err_irqreq;
+
+	ret = oxnas_rps_clockevent_init(rps);
+	if (ret)
+		goto err_irqreq;
+
+	return;
+
+err_irqreq:
+	free_irq(rps->irq, rps);
+err_iomap:
+	iounmap(base);
+err_clk_prepare:
+	clk_disable_unprepare(rps->clk);
+err_clk:
+	clk_put(rps->clk);
+err_alloc:
+	kfree(rps);
+}
+
+CLOCKSOURCE_OF_DECLARE(ox810se_rps,
+		       "oxsemi,ox810se-rps-timer", oxnas_rps_timer_init);