Currently prima2 timer can be used as a scheduler clock. We properly
marked sirfsoc_read_sched_clock() as notrace but we then call another
function sirfsoc_timer_read() that _wasn't_ notrace.

Having a traceable function in the sched_clock() path leads to a recursion
within ftrace and a kernel crash.

Fix this by adding notrace attribute to the sirfsoc_timer_read() function.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Migrate prima2 driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

In the clocksource driver, we didn't explicitly enable the clock. it makes the
clk reference counter wrong. We didn't encounter any hang issue because the
tick's clock input has been open and is shared by some other hardware
components, but if we don't enable those components in kernel, in the stage of
disabling unused clk in kernel boot, Linux tick hangs.

This patch fixes it. it does an explicit prepare and enable to the clock input,
and increases the usage counter of the clk.

Signed-off-by: Zhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Nobody want to know the connection between io clk and timer clk,
so exposing this information to timer module is not reasonable.
this patch moves to define the timers' clk in dt.

Signed-off-by: Zhiwu Song <Zhiwu.Song@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>

Fix the "line over 80 characters". users of the codes - key customers
really care about that.

WARNING: line over 80 characters
64: FILE: timer-prima2.c:64:
+       WARN_ON(!(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_STATUS) & BIT(0)));

WARNING: line over 80 characters
80: FILE: timer-prima2.c:80:
+       writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);

WARNING: line over 80 characters
82: FILE: timer-prima2.c:82:
+       cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);

WARNING: line over 80 characters
92: FILE: timer-prima2.c:92:
+       writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);

WARNING: line over 80 characters
96: FILE: timer-prima2.c:96:
+       writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);

WARNING: line over 80 characters
111: FILE: timer-prima2.c:111:
+               writel_relaxed(val | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);

WARNING: line over 80 characters
114: FILE: timer-prima2.c:114:
+               writel_relaxed(val & ~BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);

WARNING: line over 80 characters
126: FILE: timer-prima2.c:126:
+       writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);

WARNING: line over 80 characters
129: FILE: timer-prima2.c:129:
+               sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);

WARNING: line over 80 characters
137: FILE: timer-prima2.c:137:
+               writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);

WARNING: line over 80 characters
139: FILE: timer-prima2.c:139:
+       writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2], sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);

WARNING: line over 80 characters
140: FILE: timer-prima2.c:140:
+       writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1], sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);

WARNING: line over 80 characters
216: FILE: timer-prima2.c:216:
+CLOCKSOURCE_OF_DECLARE(sirfsoc_prima2_timer, "sirf,prima2-tick", sirfsoc_prima2_timer_init);

total: 0 errors, 13 warnings, 216 lines checked

timer-prima2.c has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Signed-off-by: Bin Shi <Bin.Shi@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>

Since CSR SiRF was converted to multi platform in cf82e0e (ARM: sirf:
enable multiplatform support) the symbol CLOCK_TICK_RATE isn't the
platform specific definition any more, but a global dummy value. There
was no harm introduced in cf82e0e because the global value happens to
match the old platform specific one, still this dummy value isn't
intended to be used and will hopefully disappear soon, so introduce a
local #define and use that instead.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

The 32 bit sched_clock interface now supports 64 bits. Upgrade to
the 64 bit function to allow us to remove the 32 bit registration
interface and use all 64 bits of this timer.

Cc: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>

Nothing about the sched_clock implementation in the ARM port is
specific to the architecture. Generalize the code so that other
architectures can use it by selecting GENERIC_SCHED_CLOCK.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[jstultz: Merge minor collisions with other patches in my tree]
Signed-off-by: John Stultz <john.stultz@linaro.org>

This moves the two sirf clocksource drivers to drivers/clocksource
and integrates them into the framework for locating the clock sources
automatically.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Barry Song <Baohua.Song@csr.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>