lkml.org 
[lkml]   [2013]   [Aug]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH v3 1/6] ARM/ARM64: arch timer: add m acros for bits in control register
    Date
    From
    Hi Daniel,

    On 2013-08-14 09:50, Daniel Lezcano wrote:
    > On 08/13/2013 07:29 PM, Sudeep KarkadaNagesha wrote:
    >> From: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
    >>
    >> Add macros to describe the bitfields in the ARM architected timer
    >> control register to make code easy to understand.
    >>
    >> Cc: Catalin Marinas <catalin.marinas@arm.com>
    >> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
    >> Reviewed-by: Will Deacon <will.deacon@arm.com>
    >> Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
    >> ---
    >> arch/arm/include/asm/arch_timer.h | 9 +++++++--
    >> arch/arm64/include/asm/arch_timer.h | 12 ++++++++----
    >> include/clocksource/arm_arch_timer.h | 8 ++++++++
    >> 3 files changed, 23 insertions(+), 6 deletions(-)
    >>
    >> diff --git a/arch/arm/include/asm/arch_timer.h
    >> b/arch/arm/include/asm/arch_timer.h
    >> index e406d57..9ef74da 100644
    >> --- a/arch/arm/include/asm/arch_timer.h
    >> +++ b/arch/arm/include/asm/arch_timer.h
    >> @@ -95,8 +95,13 @@ static inline void
    >> arch_counter_set_user_access(void)
    >>
    >> asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
    >>
    >> - /* disable user access to everything */
    >> - cntkctl &= ~((3 << 8) | (7 << 0));
    >> + /* Disable user access to both physical/virtual counters/timers.
    >> */
    >> + /* Also disable virtual event stream */
    >> + cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
    >> + | ARCH_TIMER_USR_VT_ACCESS_EN
    >> + | ARCH_TIMER_VIRT_EVT_EN
    >> + | ARCH_TIMER_USR_VCT_ACCESS_EN
    >> + | ARCH_TIMER_USR_PCT_ACCESS_EN);
    >>
    >> asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
    >> }
    >> diff --git a/arch/arm64/include/asm/arch_timer.h
    >> b/arch/arm64/include/asm/arch_timer.h
    >> index 98abd47..00b09d0 100644
    >> --- a/arch/arm64/include/asm/arch_timer.h
    >> +++ b/arch/arm64/include/asm/arch_timer.h
    >> @@ -101,12 +101,16 @@ static inline void
    >> arch_counter_set_user_access(void)
    >> {
    >> u32 cntkctl;
    >>
    >> - /* Disable user access to the timers and the physical counter. */
    >> asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
    >> - cntkctl &= ~((3 << 8) | (1 << 0));
    >>
    >> - /* Enable user access to the virtual counter and frequency. */
    >> - cntkctl |= (1 << 1);
    >> + /* Disable user access to the timers and the physical counter. */
    >> + cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
    >> + | ARCH_TIMER_USR_VT_ACCESS_EN
    >> + | ARCH_TIMER_USR_PCT_ACCESS_EN);
    >> +
    >> + /* Enable user access to the virtual counter. */
    >> + cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;
    >> +
    >> asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
    >> }
    >
    > Before doing those changes, I suggest you kill
    > include/asm/arch_timer.h
    > header file and move the functions directly in the arm_arch_timer.c
    > as
    > they are only used by it.

    How do you suggest to proceed? Having #ifdefs in arm_arch_timer.c to
    cope with the inline assembly functions present in both arm and arm64
    include files? Doesn't seem much of a progress to me...

    >> diff --git a/include/clocksource/arm_arch_timer.h
    >> b/include/clocksource/arm_arch_timer.h
    >> index c463ce9..551f7e9 100644
    >> --- a/include/clocksource/arm_arch_timer.h
    >> +++ b/include/clocksource/arm_arch_timer.h
    >> @@ -29,6 +29,14 @@
    >> #define ARCH_TIMER_PHYS_ACCESS 0
    >> #define ARCH_TIMER_VIRT_ACCESS 1
    >>
    >> +#define ARCH_TIMER_USR_PCT_ACCESS_EN (1 << 0) /* physical counter
    >> */
    >> +#define ARCH_TIMER_USR_VCT_ACCESS_EN (1 << 1) /* virtual counter */
    >> +#define ARCH_TIMER_VIRT_EVT_EN (1 << 2)
    >> +#define ARCH_TIMER_EVT_TRIGGER_SHIFT (4)
    >> +#define ARCH_TIMER_EVT_TRIGGER_MASK (0xF <<
    >> ARCH_TIMER_EVT_TRIGGER_SHIFT)
    >> +#define ARCH_TIMER_USR_VT_ACCESS_EN (1 << 8) /* virtual timer
    >> registers */
    >> +#define ARCH_TIMER_USR_PT_ACCESS_EN (1 << 9) /* physical timer
    >> registers */
    >> +
    >> #ifdef CONFIG_ARM_ARCH_TIMER
    >>
    >> extern u32 arch_timer_get_rate(void);
    >>

    M.
    --
    Fast, cheap, reliable. Pick two.


    \
     
     \ /
      Last update: 2013-08-14 11:21    [W:3.901 / U:0.096 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site