| Message ID | 20181017134159.9656-1-m.szyprowski@samsung.com |
|---|---|
| Headers | show |
| Series | Proper arch timer support for Exynos5433-based TM2(e) boards | expand |
Hi Marek, On 2018년 10월 17일 22:41, Marek Szyprowski wrote: > To get ARM Architected Timers working on Samsung Exynos SoCs, one has to > first configure and enable Exynos Multi-Core Timer, because they both > share some common hardware blocks (global system counter). This patch > adds a mode of cooperation with arch_timer driver, so kernel can use > CP15 based timer interface via arch_timer driver, which is mandatory > on ARM64. In such mode MCT driver only enables its clocks and starts > global timer. Everything else will be handled by arch_timer driver. > > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> > --- > drivers/clocksource/exynos_mct.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c > index 02ad55db390b..1b19a4f03929 100644 > --- a/drivers/clocksource/exynos_mct.c > +++ b/drivers/clocksource/exynos_mct.c > @@ -606,6 +606,15 @@ static int __init mct_init_dt(struct device_node *np, unsigned int int_type) > if (ret) > return ret; > > + if (IS_ENABLED(CONFIG_ARM64) && IS_ENABLED(CONFIG_ARM_ARCH_TIMER)) { > + struct device_node *np = of_find_compatible_node(NULL, NULL, > + "arm,armv8-timer"); > + if (np) { > + of_node_put(np); > + exynos4_mct_frc_start(); > + return 0; > + } > + } > > ret = exynos4_timer_interrupts(np, int_type); > if (ret) > I tested it on Exynos5433-based TM2 board. Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> -- Best Regards, Chanwoo Choi Samsung Electronics
Hi Krzysztof, On 2018-10-17 16:29, Krzysztof Kozlowski wrote: > On Wed, 17 Oct 2018 at 15:42, Marek Szyprowski <m.szyprowski@samsung.com> wrote: >> Move interrupts allocation from exynos4_timer_resources() into separate >> function together with the interrupt number parsing code from >> mct_init_dt(), so the code for managing interrupts is kept together. >> While touching exynos4_timer_resources() function, move of_iomap() to it. >> No functional changes. >> >> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> >> --- >> drivers/clocksource/exynos_mct.c | 49 +++++++++++++++++++------------- >> 1 file changed, 30 insertions(+), 19 deletions(-) >> >> diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c >> index 49413900b24c..02ad55db390b 100644 >> --- a/drivers/clocksource/exynos_mct.c >> +++ b/drivers/clocksource/exynos_mct.c >> @@ -502,11 +502,14 @@ static int exynos4_mct_dying_cpu(unsigned int cpu) >> return 0; >> } >> >> -static int __init exynos4_timer_resources(struct device_node *np, void __iomem *base) >> +static int __init exynos4_timer_resources(struct device_node *np) >> { >> - int err, cpu; >> struct clk *mct_clk, *tick_clk; >> >> + reg_base = of_iomap(np, 0); >> + if (!reg_base) >> + panic("%s: unable to ioremap mct address space\n", __func__); >> + >> tick_clk = of_clk_get_by_name(np, "fin_pll"); >> if (IS_ERR(tick_clk)) >> panic("%s: unable to determine tick clock rate\n", __func__); >> @@ -517,9 +520,27 @@ static int __init exynos4_timer_resources(struct device_node *np, void __iomem * >> panic("%s: unable to retrieve mct clock instance\n", __func__); >> clk_prepare_enable(mct_clk); >> >> - reg_base = base; >> - if (!reg_base) >> - panic("%s: unable to ioremap mct address space\n", __func__); >> + return 0; >> +} >> + >> +static int __init exynos4_timer_interrupts(struct device_node *np, >> + unsigned int int_type) >> +{ >> + int i, err, cpu; >> + >> + mct_int_type = int_type; > This does not look good. Before, assignment was done before call to > exynos4_timer_resources(). Now, if I follow the path correctly, it > will be after. Therefore the exynos4_timer_resources() will use wrong > value. This should pop up during tests. After refactoring exynos4_timer_resource() doesn't use int_type, but you are right, there is one item missing: nr_irqs as local variable, what causes the driver to mess with the global one, what is fatal to the system. I will send a fixed version in a few minutes. > ... Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
Dear All, This patchset is an attempt to submit the last piece of missing code to have proper support for Exynos5433 SoCs based TM2(e) boards. It performs a cleanup of timer configuration, which so far needed various out-of-tree workarounds. The fixes provided by this patchset are also needed for add proper support for system suspend/resume. Best regards Marek Szyprowski Samsung R&D Institute Poland Changelog: v3: - added patch, which splits resources and interrupts allocation - simplified arch timer cooperation mode - dropped CPU hotplug priority change patch, it is not really needed - removed more non-dt dead code v2: - dropped arch timer patch, it will be discussed separately - fixed issues pointed by Krzysztof Kozlowski v1: https://patchwork.kernel.org/project/linux-samsung-soc/list/?series=27965&state=*&archive=both - initial version Patch summary: Marek Szyprowski (6): clocksource: exynos_mct: Remove dead code clocksource: exynos_mct: Fix error path in timer resources initialization clocksource: exynos_mct: Refactor resources allocation clocksource: exynos_mct: Add arch_timer cooperation mode for ARM64 arm64: dts: exynos: Move arch-timer node to right place arm64: platform: Add enable Exynos Multi-Core Timer driver arch/arm64/Kconfig.platforms | 1 + arch/arm64/boot/dts/exynos/exynos5433.dtsi | 23 +++--- drivers/clocksource/exynos_mct.c | 81 ++++++++++++++-------- 3 files changed, 67 insertions(+), 38 deletions(-) -- 2.17.1