This solution keeps the virtual clock in place and enable the child
clocks before enable the virtual clock. So, any comments ?
Stanley.
On Thu, 2008-11-06 at 20:44 +0800, Stanley.Miao wrote:
> A spin_lock deadlock will occur when omap_mcbsp_request() is invoked.
>
> omap_mcbsp_request() -->
> clk_enable(mcbsp->clk) --> clk_enable get clockfw_lock, then call ->
> omap2_clk_enable() -->
> _omap2_clk_enable() -->
> omap_mcbsp_clk_enable() -->
> clk_enable(mcbsp_ick) --> now clk_enable acquire clockfw_lock again.
>
> The solution:
>
> If a alias clock has some relative clocks, enable relative clocks before enable
> the alias clock.
>
> Signed-off-by: Stanley.Miao <stanley.miao@xxxxxxxxxxxxx>
> ---
> arch/arm/mach-omap1/mcbsp.c | 67 ++++++------------------
> arch/arm/mach-omap2/mcbsp.c | 88 +++++++-----------------------
> arch/arm/plat-omap/clock.c | 9 +++-
> arch/arm/plat-omap/include/mach/clock.h | 2 +
> 4 files changed, 47 insertions(+), 119 deletions(-)
>
> diff --git a/arch/arm/mach-omap1/mcbsp.c b/arch/arm/mach-omap1/mcbsp.c
> index 7de7c69..cf220be 100644
> --- a/arch/arm/mach-omap1/mcbsp.c
> +++ b/arch/arm/mach-omap1/mcbsp.c
> @@ -26,80 +26,45 @@
> #define DPS_RSTCT2_PER_EN (1 << 0)
> #define DSP_RSTCT2_WD_PER_EN (1 << 1)
>
> -struct mcbsp_internal_clk {
> - struct clk clk;
> - struct clk **childs;
> - int n_childs;
> -};
> -
> #if defined(CONFIG_ARCH_OMAP15XX) || defined(CONFIG_ARCH_OMAP16XX)
> -static void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk)
> +static void omap_mcbsp_clk_init(struct clk *mclk)
> {
> const char *clk_names[] = { "dsp_ck", "api_ck", "dspxor_ck" };
> int i;
>
> - mclk->n_childs = ARRAY_SIZE(clk_names);
> - mclk->childs = kzalloc(mclk->n_childs * sizeof(struct clk *),
> + mclk->n_relatives = ARRAY_SIZE(clk_names);
> + mclk->relatives = kzalloc(mclk->n_relatives * sizeof(struct clk *),
> GFP_KERNEL);
>
> - for (i = 0; i < mclk->n_childs; i++) {
> + for (i = 0; i < mclk->n_relatives; i++) {
> /* We fake a platform device to get correct device id */
> struct platform_device pdev;
>
> pdev.dev.bus = &platform_bus_type;
> - pdev.id = mclk->clk.id;
> - mclk->childs[i] = clk_get(&pdev.dev, clk_names[i]);
> - if (IS_ERR(mclk->childs[i]))
> + pdev.id = mclk->id;
> + mclk->relatives[i] = clk_get(&pdev.dev, clk_names[i]);
> + if (IS_ERR(mclk->relatives[i]))
> printk(KERN_ERR "Could not get clock %s (%d).\n",
> - clk_names[i], mclk->clk.id);
> + clk_names[i], mclk->id);
> }
> }
>
> -static int omap_mcbsp_clk_enable(struct clk *clk)
> -{
> - struct mcbsp_internal_clk *mclk = container_of(clk,
> - struct mcbsp_internal_clk, clk);
> - int i;
> -
> - for (i = 0; i < mclk->n_childs; i++)
> - clk_enable(mclk->childs[i]);
> - return 0;
> -}
> -
> -static void omap_mcbsp_clk_disable(struct clk *clk)
> -{
> - struct mcbsp_internal_clk *mclk = container_of(clk,
> - struct mcbsp_internal_clk, clk);
> - int i;
> -
> - for (i = 0; i < mclk->n_childs; i++)
> - clk_disable(mclk->childs[i]);
> -}
> -
> -static struct mcbsp_internal_clk omap_mcbsp_clks[] = {
> +static struct clk omap_mcbsp_clks[] = {
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 1,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 1,
> },
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 3,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 3,
> },
> };
>
> #define omap_mcbsp_clks_size ARRAY_SIZE(omap_mcbsp_clks)
> #else
> #define omap_mcbsp_clks_size 0
> -static struct mcbsp_internal_clk __initdata *omap_mcbsp_clks;
> -static inline void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk)
> +static struct clk __initdata *omap_mcbsp_clks;
> +static inline void omap_mcbsp_clk_init(struct clk *mclk)
> { }
> #endif
>
> @@ -233,7 +198,7 @@ int __init omap1_mcbsp_init(void)
> for (i = 0; i < omap_mcbsp_clks_size; i++) {
> if (cpu_is_omap15xx() || cpu_is_omap16xx()) {
> omap_mcbsp_clk_init(&omap_mcbsp_clks[i]);
> - clk_register(&omap_mcbsp_clks[i].clk);
> + clk_register(&omap_mcbsp_clks[i]);
> }
> }
>
> diff --git a/arch/arm/mach-omap2/mcbsp.c b/arch/arm/mach-omap2/mcbsp.c
> index cae3ebe..20663e1 100644
> --- a/arch/arm/mach-omap2/mcbsp.c
> +++ b/arch/arm/mach-omap2/mcbsp.c
> @@ -22,103 +22,57 @@
> #include <mach/cpu.h>
> #include <mach/mcbsp.h>
>
> -struct mcbsp_internal_clk {
> - struct clk clk;
> - struct clk **childs;
> - int n_childs;
> -};
> -
> #if defined(CONFIG_ARCH_OMAP24XX) || defined(CONFIG_ARCH_OMAP34XX)
> -static void omap_mcbsp_clk_init(struct mcbsp_internal_clk *mclk)
> +static void omap_mcbsp_clk_init(struct clk *mclk)
> {
> const char *clk_names[] = { "mcbsp_ick", "mcbsp_fck" };
> int i;
>
> - mclk->n_childs = ARRAY_SIZE(clk_names);
> - mclk->childs = kzalloc(mclk->n_childs * sizeof(struct clk *),
> + mclk->n_relatives = ARRAY_SIZE(clk_names);
> + mclk->relatives = kzalloc(mclk->n_relatives * sizeof(struct clk *),
> GFP_KERNEL);
>
> - for (i = 0; i < mclk->n_childs; i++) {
> + for (i = 0; i < mclk->n_relatives; i++) {
> /* We fake a platform device to get correct device id */
> struct platform_device pdev;
>
> pdev.dev.bus = &platform_bus_type;
> - pdev.id = mclk->clk.id;
> - mclk->childs[i] = clk_get(&pdev.dev, clk_names[i]);
> - if (IS_ERR(mclk->childs[i]))
> + pdev.id = mclk->id;
> + mclk->relatives[i] = clk_get(&pdev.dev, clk_names[i]);
> + if (IS_ERR(mclk->relatives[i]))
> printk(KERN_ERR "Could not get clock %s (%d).\n",
> - clk_names[i], mclk->clk.id);
> + clk_names[i], mclk->id);
> }
> }
>
> -static int omap_mcbsp_clk_enable(struct clk *clk)
> -{
> - struct mcbsp_internal_clk *mclk = container_of(clk,
> - struct mcbsp_internal_clk, clk);
> - int i;
> -
> - for (i = 0; i < mclk->n_childs; i++)
> - clk_enable(mclk->childs[i]);
> - return 0;
> -}
> -
> -static void omap_mcbsp_clk_disable(struct clk *clk)
> -{
> - struct mcbsp_internal_clk *mclk = container_of(clk,
> - struct mcbsp_internal_clk, clk);
> - int i;
> -
> - for (i = 0; i < mclk->n_childs; i++)
> - clk_disable(mclk->childs[i]);
> -}
>
> -static struct mcbsp_internal_clk omap_mcbsp_clks[] = {
> +static struct clk omap_mcbsp_clks[] = {
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 1,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 1,
> },
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 2,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 2,
> },
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 3,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 3,
> },
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 4,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 4,
> },
> {
> - .clk = {
> - .name = "mcbsp_clk",
> - .id = 5,
> - .enable = omap_mcbsp_clk_enable,
> - .disable = omap_mcbsp_clk_disable,
> - },
> + .name = "mcbsp_clk",
> + .id = 5,
> },
> };
>
> #define omap_mcbsp_clks_size ARRAY_SIZE(omap_mcbsp_clks)
> #else
> #define omap_mcbsp_clks_size 0
> -static struct mcbsp_internal_clk __initdata *omap_mcbsp_clks;
> +static struct clk __initdata *omap_mcbsp_clks;
> static inline void omap_mcbsp_clk_init(struct clk *clk)
> { }
> #endif
> @@ -287,7 +241,7 @@ static int __init omap2_mcbsp_init(void)
> for (i = 0; i < omap_mcbsp_clks_size; i++) {
> /* Once we call clk_get inside init, we do not register it */
> omap_mcbsp_clk_init(&omap_mcbsp_clks[i]);
> - clk_register(&omap_mcbsp_clks[i].clk);
> + clk_register(&omap_mcbsp_clks[i]);
> }
>
> if (cpu_is_omap2420())
> diff --git a/arch/arm/plat-omap/clock.c b/arch/arm/plat-omap/clock.c
> index d13acd2..1c4f877 100644
> --- a/arch/arm/plat-omap/clock.c
> +++ b/arch/arm/plat-omap/clock.c
> @@ -77,11 +77,14 @@ EXPORT_SYMBOL(clk_get);
> int clk_enable(struct clk *clk)
> {
> unsigned long flags;
> - int ret = 0;
> + int i, ret = 0;
>
> if (clk == NULL || IS_ERR(clk))
> return -EINVAL;
>
> + for (i = 0; i < clk->n_relatives; i++)
> + clk_enable(clk->relatives[i]);
> +
> spin_lock_irqsave(&clockfw_lock, flags);
> if (arch_clock->clk_enable)
> ret = arch_clock->clk_enable(clk);
> @@ -94,10 +97,14 @@ EXPORT_SYMBOL(clk_enable);
> void clk_disable(struct clk *clk)
> {
> unsigned long flags;
> + int i;
>
> if (clk == NULL || IS_ERR(clk))
> return;
>
> + for (i = 0; i < clk->n_relatives; i++)
> + clk_disable(clk->relatives[i]);
> +
> spin_lock_irqsave(&clockfw_lock, flags);
> if (clk->usecount == 0) {
> printk(KERN_ERR "Trying disable clock %s with 0 usecount\n",
> diff --git a/arch/arm/plat-omap/include/mach/clock.h b/arch/arm/plat-omap/include/mach/clock.h
> index 9088925..2760bcf 100644
> --- a/arch/arm/plat-omap/include/mach/clock.h
> +++ b/arch/arm/plat-omap/include/mach/clock.h
> @@ -71,6 +71,8 @@ struct clk {
> __u8 enable_bit;
> __s8 usecount;
> u8 idlest_bit;
> + struct clk **relatives;
> + int n_relatives;
> void (*recalc)(struct clk *);
> int (*set_rate)(struct clk *, unsigned long);
> long (*round_rate)(struct clk *, unsigned long);
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
