13 Mar, 2015

1 commit

  • of_clk_get_by_clkspec() has the same function signature as
    of_clk_get_from_provider()

    struct clk *of_clk_get_by_clkspec(struct of_phandle_args
    *clkspec)
    struct clk *of_clk_get_from_provider(struct of_phandle_args
    *clkspec)

    except of_clk_get_by_clkspec() checks to make sure clkspec is not
    NULL. Let's remove of_clk_get_by_clkspec() and replace the
    callers of it (clkconf.c) with of_clk_get_from_provider().

    Cc: Sylwester Nawrocki
    Reviewed-by: Tomeu Vizoso
    Signed-off-by: Stephen Boyd

    Stephen Boyd
     

07 Feb, 2015

1 commit

  • of_clk_get_by_clkspec() returns a struct clk pointer but it
    doesn't create a new handle for the consumers when we're using
    the common clock framework. Instead it just returns whatever the
    clk provider hands out. When the consumers go to call clk_put()
    we get an Oops.

    Unable to handle kernel paging request at virtual address 00200200
    pgd = c0004000
    [00200200] *pgd=00000000
    Internal error: Oops: 805 [#1] PREEMPT SMP ARM
    Modules linked in:
    CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.19.0-rc1-00104-ga251361a-dirty #992
    Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
    task: ee00b000 ti: ee088000 task.ti: ee088000
    PC is at __clk_put+0x24/0xd0
    LR is at clk_prepare_lock+0xc/0xec
    pc : [] lr : [] psr: 20000153
    sp : ee089de8 ip : 00000000 fp : 00000000
    r10: ee02f480 r9 : 00000001 r8 : 00000000
    r7 : ee031cc0 r6 : ee089e08 r5 : 00000000 r4 : ee02f480
    r3 : 00100100 r2 : 00200200 r1 : 0000091e r0 : 00000001
    Flags: nzCv IRQs on FIQs off Mode SVC_32 ISA ARM Segment kernel
    Control: 10c5387d Table: 4000404a DAC: 00000015
    Process swapper/0 (pid: 1, stack limit = 0xee088238)
    Stack: (0xee089de8 to 0xee08a000)
    9de0: ee7c8f14 c03f0ec8 ee089e08 00000000 c0718dc8 00000001
    9e00: 00000000 c04ee0f0 ee7e0844 00000001 00000181 c04edb58 ee2bd320 00000000
    9e20: 00000000 c011dc5c ee16a1e0 00000000 00000000 c0718dc8 ee16a1e0 ee2bd1e0
    9e40: c0641740 ee16a1e0 00000000 ee2bd320 c0718dc8 ee1d3e10 ee1d3e10 00000000
    9e60: c0769a88 00000000 c0718dc8 00000000 00000000 c02c3124 c02c310c ee1d3e10
    9e80: c07b4eec 00000000 c0769a88 c02c1d0c ee1d3e10 c0769a88 ee1d3e44 00000000
    9ea0: c07091dc c02c1eb8 00000000 c0769a88 c02c1e2c c02c0544 ee005478 ee1676c0
    9ec0: c0769a88 ee3a4e80 c0760ce8 c02c150c c0669b90 c0769a88 c0746cd8 c0769a88
    9ee0: c0746cd8 ee2bc4c0 c0778c00 c02c24e0 00000000 c0746cd8 c0746cd8 c07091f0
    9f00: 00000000 c0008944 c04f405c 00000025 ee00b000 60000153 c074ab00 00000000
    9f20: 00000000 c074ab90 60000153 00000000 ef7fca5d c050860c 000000b6 c0036b88
    9f40: c065ecc4 c06bc728 00000006 00000006 c074ab30 ef7fca40 c0739bdc 00000006
    9f60: c0718dbc c0778c00 000000b6 c0718dc8 c06ed598 c06edd64 00000006 00000006
    9f80: c06ed598 c003b438 00000000 c04e64f4 00000000 00000000 00000000 00000000
    9fa0: 00000000 c04e64fc 00000000 c000e838 00000000 00000000 00000000 00000000
    9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
    9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 c0c0c0c0 c0c0c0c0
    [] (__clk_put) from [] (of_clk_set_defaults+0xe0/0x2c0)
    [] (of_clk_set_defaults) from [] (platform_drv_probe+0x18/0xa4)
    [] (platform_drv_probe) from [] (driver_probe_device+0x10c/0x22c)
    [] (driver_probe_device) from [] (__driver_attach+0x8c/0x90)
    [] (__driver_attach) from [] (bus_for_each_dev+0x54/0x88)
    [] (bus_for_each_dev) from [] (bus_add_driver+0xd4/0x1d0)
    [] (bus_add_driver) from [] (driver_register+0x78/0xf4)
    [] (driver_register) from [] (fimc_md_init+0x14/0x30)
    [] (fimc_md_init) from [] (do_one_initcall+0x80/0x1d0)
    [] (do_one_initcall) from [] (kernel_init_freeable+0x108/0x1d4)
    [] (kernel_init_freeable) from [] (kernel_init+0x8/0xec)
    [] (kernel_init) from [] (ret_from_fork+0x14/0x3c)
    Code: ebfff4ae e5943014 e5942018 e3530000 (e5823000)

    Let's create a per-user handle here so that clk_put() can
    properly unlink it and free the handle. Now that we allocate a
    clk structure here we need to free it if __clk_get() fails so
    bury the __clk_get() call in __of_clk_get_from_provider(). We
    need to handle the same problem in clk_get_sys() so export
    __clk_free_clk() to clkdev.c and do the same thing, except let's
    use a union to make this code #ifdef free.

    This fixes the above crash, properly calls __clk_get() when
    of_clk_get_from_provider() is called, and cleans up the clk
    structure on the error path of clk_get_sys().

    Fixes: 035a61c314eb "clk: Make clk API return per-user struct clk instances"
    Reported-by: Sylwester Nawrocki
    Reported-by: Alban Browaeys
    Tested-by: Sylwester Nawrocki
    Tested-by: Alban Browaeys
    Reviewed-by: Tomeu Vizoso
    Signed-off-by: Stephen Boyd
    Signed-off-by: Michael Turquette

    Stephen Boyd
     

03 Feb, 2015

1 commit

  • Moves clock state to struct clk_core, but takes care to change as little API as
    possible.

    struct clk_hw still has a pointer to a struct clk, which is the
    implementation's per-user clk instance, for backwards compatibility.

    The struct clk that clk_get_parent() returns isn't owned by the caller, but by
    the clock implementation, so the former shouldn't call clk_put() on it.

    Because some boards in mach-omap2 still register clocks statically, their clock
    registration had to be updated to take into account that the clock information
    is stored in struct clk_core now.

    Signed-off-by: Tomeu Vizoso
    Reviewed-by: Stephen Boyd
    Tested-by: Tony Lindgren
    Signed-off-by: Michael Turquette
    [mturquette@linaro.org: adapted clk_has_parent to struct clk_core
    applied OMAP3+ DPLL fix from Tero & Tony]

    Tomeu Vizoso
     

23 May, 2014

1 commit

  • This patch adds of_clk_get_by_clkspec() helper function, which does only
    a struct clk lookup from the clock providers. It is used in the subsequent
    patch where parsing of a clock from device tree and the lookup from
    providers needed to be split.

    Signed-off-by: Sylwester Nawrocki
    Signed-off-by: Mike Turquette

    Sylwester Nawrocki
     

05 Dec, 2013

1 commit