* stanley.miao <stanley.miao@xxxxxxxxxxxxx> [081107 15:47]:
> This solution keeps the virtual clock in place and enable the child
> clocks before enable the virtual clock. So, any comments ?
What if we just removed the custom clock and had a struct **clk
in struct omap_mcbsp that contains the clocks for each instance?
Regards,
Tony
> 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
--
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
