| Message ID | 1401101095-27181-1-git-send-email-archit@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Monday 26 May 2014 04:14 PM, Archit Taneja wrote: > Generally, IP blocks/modules within a clock domain each have their own > CM_x_CLKCTRL register, each having it's own MODULEMODE field to manage the > module. > > DSS clockdoain, however, has multiple modules in it, but only one register > named CM_DSS_DSS_CLKCTRL, which contains one MODULEMODE register field. > > Until now, we defined '.prcm.omap4.modulemode' only for the top level DSS > hwmod("dss_core") and didn't define it for other DSS hwmods(like "dss_dispc", > "dss_dsi1" and so on). This made the omapdss driver work as the top level DSS > platform device and the rest had a parent-child relationship. This ensured that > the parent hwmod("dss_core") is enabled if any of the children hwmods are > enabled while using omapdss. > > This method, however, doesn't work when each hwmod is enabled individually. > This happens early in boot in omap_hwmod_setup_all, where each hwmod is enabled, > and then reset and idled. All the 'children' DSS hwmods fail to enable and > reset, since they don't enable modulemode. > > The way to make such modules work both during initialization and when used by > pm runtime API in the driver would be to add refcounting for enabling/disabling > the modulemode field. > > We add a new flag bit for the flag in omap_hwmod_omap4_prcm, which tells > omap_hwmod that this hwmod uses a modulemode field shared by other hwmods. > > We create a struct called 'modulemode_shared'. The hwmod data file should define > a static instance of this struct. Each hwmod that uses this modulemode field > should hold a pointer to this instance. > > omap_hwmod's soc enable_module and disable_module ops set the MODULEMODE > reigster bits only when the first module using it is enabled, or the last module > using it is disabled. We serialize accesses to the struct with a spinlock. > > Signed-off-by: Archit Taneja <archit@ti.com> > --- > arch/arm/mach-omap2/omap_hwmod.c | 123 +++++++++++++++++++++++++++++++++------ > arch/arm/mach-omap2/omap_hwmod.h | 38 +++++++++--- > 2 files changed, 133 insertions(+), 28 deletions(-) > > diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c > index 66c60fe..b42718d 100644 > --- a/arch/arm/mach-omap2/omap_hwmod.c > +++ b/arch/arm/mach-omap2/omap_hwmod.c > @@ -973,17 +973,33 @@ static void _disable_optional_clocks(struct omap_hwmod *oh) > */ > static void _omap4_enable_module(struct omap_hwmod *oh) > { > + unsigned long flags; > + struct modulemode_shared *mmode = NULL; > + bool enable = true; > + > if (!oh->clkdm || !oh->prcm.omap4.modulemode) > return; > > pr_debug("omap_hwmod: %s: %s: %d\n", > oh->name, __func__, oh->prcm.omap4.modulemode); > > - omap4_cminst_module_enable(oh->prcm.omap4.modulemode, > - oh->clkdm->prcm_partition, > - oh->clkdm->cm_inst, > - oh->clkdm->clkdm_offs, > - oh->prcm.omap4.clkctrl_offs); > + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { > + mmode = oh->prcm.omap4.modulemode_ref; > + > + spin_lock_irqsave(&mmode->lock, flags); > + > + enable = mmode->refcnt++ == 0; > + } > + > + if (enable) > + omap4_cminst_module_enable(oh->prcm.omap4.modulemode, > + oh->clkdm->prcm_partition, > + oh->clkdm->cm_inst, > + oh->clkdm->clkdm_offs, > + oh->prcm.omap4.clkctrl_offs); > + > + if (mmode) > + spin_unlock_irqrestore(&mmode->lock, flags); > } > > /** > @@ -995,15 +1011,32 @@ static void _omap4_enable_module(struct omap_hwmod *oh) > */ > static void _am33xx_enable_module(struct omap_hwmod *oh) > { > + unsigned long flags; > + struct modulemode_shared *mmode = NULL; > + bool enable = true; > + > if (!oh->clkdm || !oh->prcm.omap4.modulemode) > return; > > pr_debug("omap_hwmod: %s: %s: %d\n", > oh->name, __func__, oh->prcm.omap4.modulemode); > > - am33xx_cm_module_enable(oh->prcm.omap4.modulemode, oh->clkdm->cm_inst, > - oh->clkdm->clkdm_offs, > - oh->prcm.omap4.clkctrl_offs); > + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { > + mmode = oh->prcm.omap4.modulemode_ref; > + > + spin_lock_irqsave(&mmode->lock, flags); > + > + enable = mmode->refcnt++ == 0; > + } > + > + if (enable) > + am33xx_cm_module_enable(oh->prcm.omap4.modulemode, > + oh->clkdm->cm_inst, > + oh->clkdm->clkdm_offs, > + oh->prcm.omap4.clkctrl_offs); > + > + if (mmode) > + spin_unlock_irqrestore(&mmode->lock, flags); > } > > /** > @@ -1846,6 +1879,9 @@ static bool _are_any_hardreset_lines_asserted(struct omap_hwmod *oh) > static int _omap4_disable_module(struct omap_hwmod *oh) > { > int v; > + unsigned long flags; > + struct modulemode_shared *mmode = NULL; > + bool disable = true; > > if (!oh->clkdm || !oh->prcm.omap4.modulemode) > return -EINVAL; > @@ -1859,15 +1895,30 @@ static int _omap4_disable_module(struct omap_hwmod *oh) > > pr_debug("omap_hwmod: %s: %s\n", oh->name, __func__); > > - omap4_cminst_module_disable(oh->clkdm->prcm_partition, > + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { > + mmode = oh->prcm.omap4.modulemode_ref; > + > + spin_lock_irqsave(&mmode->lock, flags); > + > + WARN_ON(mmode->refcnt == 0); > + > + disable = --mmode->refcnt == 0; > + } > + > + if (disable) { > + omap4_cminst_module_disable(oh->clkdm->prcm_partition, > oh->clkdm->cm_inst, > oh->clkdm->clkdm_offs, > oh->prcm.omap4.clkctrl_offs); > > - v = _omap4_wait_target_disable(oh); > - if (v) > - pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", > - oh->name); > + v = _omap4_wait_target_disable(oh); > + if (v) > + pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", > + oh->name); > + } > + > + if (mmode) > + spin_unlock_irqrestore(&mmode->lock, flags); > > return 0; > } > @@ -1882,6 +1933,9 @@ static int _omap4_disable_module(struct omap_hwmod *oh) > static int _am33xx_disable_module(struct omap_hwmod *oh) > { > int v; > + unsigned long flags; > + struct modulemode_shared *mmode = NULL; > + bool disable = true; > > if (!oh->clkdm || !oh->prcm.omap4.modulemode) > return -EINVAL; > @@ -1891,13 +1945,28 @@ static int _am33xx_disable_module(struct omap_hwmod *oh) > if (_are_any_hardreset_lines_asserted(oh)) > return 0; > > - am33xx_cm_module_disable(oh->clkdm->cm_inst, oh->clkdm->clkdm_offs, > - oh->prcm.omap4.clkctrl_offs); > + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { > + mmode = oh->prcm.omap4.modulemode_ref; > > - v = _am33xx_wait_target_disable(oh); > - if (v) > - pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", > - oh->name); > + spin_lock_irqsave(&mmode->lock, flags); > + > + WARN_ON(mmode->refcnt == 0); > + > + disable = --mmode->refcnt == 0; > + } > + > + if (disable) { > + am33xx_cm_module_disable(oh->clkdm->cm_inst, oh->clkdm->clkdm_offs, > + oh->prcm.omap4.clkctrl_offs); > + > + v = _am33xx_wait_target_disable(oh); > + if (v) > + pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", > + oh->name); > + } > + > + if (mmode) > + spin_unlock_irqrestore(&mmode->lock, flags); > > return 0; > } > @@ -2751,6 +2820,13 @@ static int __init _register(struct omap_hwmod *oh) > if (_lookup(oh->name)) > return -EEXIST; > > + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED && > + !oh->prcm.omap4.modulemode_ref) { You might also want to check for someone populating a modulemode_ref but failing to populate the flag? Alternatively, Since you expect a modulemode_ref to be always available for all modules which share modulemode, that in itself can be used to identify such modules without the need of an additional flag? > + pr_err("omap_hwmod: %s shares modulemode, but doesn't hold a ref to it\n", > + oh->name); > + return -EINVAL; > + } > + > list_add_tail(&oh->node, &omap_hwmod_list); > > INIT_LIST_HEAD(&oh->master_ports); > @@ -2759,6 +2835,15 @@ static int __init _register(struct omap_hwmod *oh) > > oh->_state = _HWMOD_STATE_REGISTERED; > > + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { > + struct modulemode_shared *mmode = oh->prcm.omap4.modulemode_ref; > + > + if (!mmode->registered) { > + spin_lock_init(&mmode->lock); > + mmode->registered = true; If this is only used to keep track of the spin_lock being initialized, maybe it'll be more readable if you just call it mmode->spin_lock_init = true. > + } > + } > + > /* > * XXX Rather than doing a strcmp(), this should test a flag > * set in the hwmod data, inserted by the autogenerator code. > diff --git a/arch/arm/mach-omap2/omap_hwmod.h b/arch/arm/mach-omap2/omap_hwmod.h > index 0f97d63..64c2af6 100644 > --- a/arch/arm/mach-omap2/omap_hwmod.h > +++ b/arch/arm/mach-omap2/omap_hwmod.h > @@ -432,13 +432,31 @@ struct omap_hwmod_omap2_prcm { > }; > > /* > + * struct for managing modulemode field shared accross IP blocks > + * @lock: spinlock to searilze enables/disables performed by different > + * hwmods sharing the same modulemode field > + * @refcnt: keep a refcount of the enabled hwmods using this modulemode > + * field > + * @registered: a flag to track whether the struct has been registered > + */ > +struct modulemode_shared { > + spinlock_t lock; > + unsigned refcnt; > + bool registered; > +}; > + > +/* > * Possible values for struct omap_hwmod_omap4_prcm.flags > * > * HWMOD_OMAP4_NO_CONTEXT_LOSS_BIT: Some IP blocks don't have a PRCM > * module-level context loss register associated with them; this > * flag bit should be set in those cases > + * HWMOD_OMAP4_MODULEMODE_SHARED: Some IP blocks belonging to the same > + * clock domain may have a shared MODULEMODE field; this flag bit > + * should be set in those cases > */ > #define HWMOD_OMAP4_NO_CONTEXT_LOSS_BIT (1 << 0) > +#define HWMOD_OMAP4_MODULEMODE_SHARED (1 << 1) > > /** > * struct omap_hwmod_omap4_prcm - OMAP4-specific PRCM data > @@ -450,6 +468,7 @@ struct omap_hwmod_omap2_prcm { > * @submodule_wkdep_bit: bit shift of the WKDEP range > * @flags: PRCM register capabilities for this IP block > * @modulemode: allowable modulemodes > + * @modulemode_ref: pointer to modulemode struct shared by multiple hwmods > * @context_lost_counter: Count of module level context lost > * > * If @lostcontext_mask is not defined, context loss check code uses > @@ -458,15 +477,16 @@ struct omap_hwmod_omap2_prcm { > * more hwmods. > */ > struct omap_hwmod_omap4_prcm { > - u16 clkctrl_offs; > - u16 rstctrl_offs; > - u16 rstst_offs; > - u16 context_offs; > - u32 lostcontext_mask; > - u8 submodule_wkdep_bit; > - u8 modulemode; > - u8 flags; > - int context_lost_counter; > + u16 clkctrl_offs; > + u16 rstctrl_offs; > + u16 rstst_offs; > + u16 context_offs; > + u32 lostcontext_mask; > + u8 submodule_wkdep_bit; > + u8 modulemode; > + struct modulemode_shared *modulemode_ref; > + u8 flags; > + int context_lost_counter; > }; > > > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On Tuesday 27 May 2014 03:50 PM, Rajendra Nayak wrote: > On Monday 26 May 2014 04:14 PM, Archit Taneja wrote: >> Generally, IP blocks/modules within a clock domain each have their own >> CM_x_CLKCTRL register, each having it's own MODULEMODE field to manage the >> module. <snip> >> @@ -2751,6 +2820,13 @@ static int __init _register(struct omap_hwmod *oh) >> if (_lookup(oh->name)) >> return -EEXIST; >> >> + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED && >> + !oh->prcm.omap4.modulemode_ref) { > > You might also want to check for someone populating a modulemode_ref but > failing to populate the flag? > > Alternatively, Since you expect a modulemode_ref to be always available for all modules which > share modulemode, that in itself can be used to identify such modules without the > need of an additional flag? It does seem redundant to have a flag at the moment. But the flag make things more visible. 'prcm.omap4.modulemode' seems to work without a flag too, so I suppose I'll remove the flag. > >> + pr_err("omap_hwmod: %s shares modulemode, but doesn't hold a ref to it\n", >> + oh->name); >> + return -EINVAL; >> + } >> + >> list_add_tail(&oh->node, &omap_hwmod_list); >> >> INIT_LIST_HEAD(&oh->master_ports); >> @@ -2759,6 +2835,15 @@ static int __init _register(struct omap_hwmod *oh) >> >> oh->_state = _HWMOD_STATE_REGISTERED; >> >> + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { >> + struct modulemode_shared *mmode = oh->prcm.omap4.modulemode_ref; >> + >> + if (!mmode->registered) { >> + spin_lock_init(&mmode->lock); >> + mmode->registered = true; > > If this is only used to keep track of the spin_lock being initialized, maybe it'll be > more readable if you just call it mmode->spin_lock_init = true. Yes, I'll fix this. Archit -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
IP blocks within a clock domain generally come with their own CM_X_CLKCTRL
registers, each having it's own MODULEMODE field to manage the module. This is
not the case for DSS, though. DSS contains contains sub modules, each of which
are represented by hwmods, but DSS itself has only one register
CM_DSS_DSS_CLKCTRL.
Add a way to allow multiple hwmods to share the same MODULEMODE fiels. This
means that MODULEMODE operation should be disabled only when the last hwmod
using it is disabled.
Changes in v2:
- The OMAP4 PRCM hwmod flag to show that this hwmod is shared was found
redundant, and therefore, removed.
- Some of the struct names are shortened, and members are named more
appropriately.
Archit Taneja (2):
arm: omap2+: hwmod: Add refcounting for modulemode shared by multiple
hwmods
arm: omap5 hwmod data: Example: Make DSS hwmods share MODULEMODE
fields
arch/arm/mach-omap2/omap_hwmod.c | 145 +++++++++++++++++++++++++----
arch/arm/mach-omap2/omap_hwmod.h | 35 +++++--
arch/arm/mach-omap2/omap_hwmod_54xx_data.c | 40 +++++---
3 files changed, 180 insertions(+), 40 deletions(-)
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c index 66c60fe..b42718d 100644 --- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -973,17 +973,33 @@ static void _disable_optional_clocks(struct omap_hwmod *oh) */ static void _omap4_enable_module(struct omap_hwmod *oh) { + unsigned long flags; + struct modulemode_shared *mmode = NULL; + bool enable = true; + if (!oh->clkdm || !oh->prcm.omap4.modulemode) return; pr_debug("omap_hwmod: %s: %s: %d\n", oh->name, __func__, oh->prcm.omap4.modulemode); - omap4_cminst_module_enable(oh->prcm.omap4.modulemode, - oh->clkdm->prcm_partition, - oh->clkdm->cm_inst, - oh->clkdm->clkdm_offs, - oh->prcm.omap4.clkctrl_offs); + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { + mmode = oh->prcm.omap4.modulemode_ref; + + spin_lock_irqsave(&mmode->lock, flags); + + enable = mmode->refcnt++ == 0; + } + + if (enable) + omap4_cminst_module_enable(oh->prcm.omap4.modulemode, + oh->clkdm->prcm_partition, + oh->clkdm->cm_inst, + oh->clkdm->clkdm_offs, + oh->prcm.omap4.clkctrl_offs); + + if (mmode) + spin_unlock_irqrestore(&mmode->lock, flags); } /** @@ -995,15 +1011,32 @@ static void _omap4_enable_module(struct omap_hwmod *oh) */ static void _am33xx_enable_module(struct omap_hwmod *oh) { + unsigned long flags; + struct modulemode_shared *mmode = NULL; + bool enable = true; + if (!oh->clkdm || !oh->prcm.omap4.modulemode) return; pr_debug("omap_hwmod: %s: %s: %d\n", oh->name, __func__, oh->prcm.omap4.modulemode); - am33xx_cm_module_enable(oh->prcm.omap4.modulemode, oh->clkdm->cm_inst, - oh->clkdm->clkdm_offs, - oh->prcm.omap4.clkctrl_offs); + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { + mmode = oh->prcm.omap4.modulemode_ref; + + spin_lock_irqsave(&mmode->lock, flags); + + enable = mmode->refcnt++ == 0; + } + + if (enable) + am33xx_cm_module_enable(oh->prcm.omap4.modulemode, + oh->clkdm->cm_inst, + oh->clkdm->clkdm_offs, + oh->prcm.omap4.clkctrl_offs); + + if (mmode) + spin_unlock_irqrestore(&mmode->lock, flags); } /** @@ -1846,6 +1879,9 @@ static bool _are_any_hardreset_lines_asserted(struct omap_hwmod *oh) static int _omap4_disable_module(struct omap_hwmod *oh) { int v; + unsigned long flags; + struct modulemode_shared *mmode = NULL; + bool disable = true; if (!oh->clkdm || !oh->prcm.omap4.modulemode) return -EINVAL; @@ -1859,15 +1895,30 @@ static int _omap4_disable_module(struct omap_hwmod *oh) pr_debug("omap_hwmod: %s: %s\n", oh->name, __func__); - omap4_cminst_module_disable(oh->clkdm->prcm_partition, + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { + mmode = oh->prcm.omap4.modulemode_ref; + + spin_lock_irqsave(&mmode->lock, flags); + + WARN_ON(mmode->refcnt == 0); + + disable = --mmode->refcnt == 0; + } + + if (disable) { + omap4_cminst_module_disable(oh->clkdm->prcm_partition, oh->clkdm->cm_inst, oh->clkdm->clkdm_offs, oh->prcm.omap4.clkctrl_offs); - v = _omap4_wait_target_disable(oh); - if (v) - pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", - oh->name); + v = _omap4_wait_target_disable(oh); + if (v) + pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", + oh->name); + } + + if (mmode) + spin_unlock_irqrestore(&mmode->lock, flags); return 0; } @@ -1882,6 +1933,9 @@ static int _omap4_disable_module(struct omap_hwmod *oh) static int _am33xx_disable_module(struct omap_hwmod *oh) { int v; + unsigned long flags; + struct modulemode_shared *mmode = NULL; + bool disable = true; if (!oh->clkdm || !oh->prcm.omap4.modulemode) return -EINVAL; @@ -1891,13 +1945,28 @@ static int _am33xx_disable_module(struct omap_hwmod *oh) if (_are_any_hardreset_lines_asserted(oh)) return 0; - am33xx_cm_module_disable(oh->clkdm->cm_inst, oh->clkdm->clkdm_offs, - oh->prcm.omap4.clkctrl_offs); + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { + mmode = oh->prcm.omap4.modulemode_ref; - v = _am33xx_wait_target_disable(oh); - if (v) - pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", - oh->name); + spin_lock_irqsave(&mmode->lock, flags); + + WARN_ON(mmode->refcnt == 0); + + disable = --mmode->refcnt == 0; + } + + if (disable) { + am33xx_cm_module_disable(oh->clkdm->cm_inst, oh->clkdm->clkdm_offs, + oh->prcm.omap4.clkctrl_offs); + + v = _am33xx_wait_target_disable(oh); + if (v) + pr_warn("omap_hwmod: %s: _wait_target_disable failed\n", + oh->name); + } + + if (mmode) + spin_unlock_irqrestore(&mmode->lock, flags); return 0; } @@ -2751,6 +2820,13 @@ static int __init _register(struct omap_hwmod *oh) if (_lookup(oh->name)) return -EEXIST; + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED && + !oh->prcm.omap4.modulemode_ref) { + pr_err("omap_hwmod: %s shares modulemode, but doesn't hold a ref to it\n", + oh->name); + return -EINVAL; + } + list_add_tail(&oh->node, &omap_hwmod_list); INIT_LIST_HEAD(&oh->master_ports); @@ -2759,6 +2835,15 @@ static int __init _register(struct omap_hwmod *oh) oh->_state = _HWMOD_STATE_REGISTERED; + if (oh->prcm.omap4.flags & HWMOD_OMAP4_MODULEMODE_SHARED) { + struct modulemode_shared *mmode = oh->prcm.omap4.modulemode_ref; + + if (!mmode->registered) { + spin_lock_init(&mmode->lock); + mmode->registered = true; + } + } + /* * XXX Rather than doing a strcmp(), this should test a flag * set in the hwmod data, inserted by the autogenerator code. diff --git a/arch/arm/mach-omap2/omap_hwmod.h b/arch/arm/mach-omap2/omap_hwmod.h index 0f97d63..64c2af6 100644 --- a/arch/arm/mach-omap2/omap_hwmod.h +++ b/arch/arm/mach-omap2/omap_hwmod.h @@ -432,13 +432,31 @@ struct omap_hwmod_omap2_prcm { }; /* + * struct for managing modulemode field shared accross IP blocks + * @lock: spinlock to searilze enables/disables performed by different + * hwmods sharing the same modulemode field + * @refcnt: keep a refcount of the enabled hwmods using this modulemode + * field + * @registered: a flag to track whether the struct has been registered + */ +struct modulemode_shared { + spinlock_t lock; + unsigned refcnt; + bool registered; +}; + +/* * Possible values for struct omap_hwmod_omap4_prcm.flags * * HWMOD_OMAP4_NO_CONTEXT_LOSS_BIT: Some IP blocks don't have a PRCM * module-level context loss register associated with them; this * flag bit should be set in those cases + * HWMOD_OMAP4_MODULEMODE_SHARED: Some IP blocks belonging to the same + * clock domain may have a shared MODULEMODE field; this flag bit + * should be set in those cases */ #define HWMOD_OMAP4_NO_CONTEXT_LOSS_BIT (1 << 0) +#define HWMOD_OMAP4_MODULEMODE_SHARED (1 << 1) /** * struct omap_hwmod_omap4_prcm - OMAP4-specific PRCM data @@ -450,6 +468,7 @@ struct omap_hwmod_omap2_prcm { * @submodule_wkdep_bit: bit shift of the WKDEP range * @flags: PRCM register capabilities for this IP block * @modulemode: allowable modulemodes + * @modulemode_ref: pointer to modulemode struct shared by multiple hwmods * @context_lost_counter: Count of module level context lost * * If @lostcontext_mask is not defined, context loss check code uses @@ -458,15 +477,16 @@ struct omap_hwmod_omap2_prcm { * more hwmods. */ struct omap_hwmod_omap4_prcm { - u16 clkctrl_offs; - u16 rstctrl_offs; - u16 rstst_offs; - u16 context_offs; - u32 lostcontext_mask; - u8 submodule_wkdep_bit; - u8 modulemode; - u8 flags; - int context_lost_counter; + u16 clkctrl_offs; + u16 rstctrl_offs; + u16 rstst_offs; + u16 context_offs; + u32 lostcontext_mask; + u8 submodule_wkdep_bit; + u8 modulemode; + struct modulemode_shared *modulemode_ref; + u8 flags; + int context_lost_counter; };
Generally, IP blocks/modules within a clock domain each have their own CM_x_CLKCTRL register, each having it's own MODULEMODE field to manage the module. DSS clockdoain, however, has multiple modules in it, but only one register named CM_DSS_DSS_CLKCTRL, which contains one MODULEMODE register field. Until now, we defined '.prcm.omap4.modulemode' only for the top level DSS hwmod("dss_core") and didn't define it for other DSS hwmods(like "dss_dispc", "dss_dsi1" and so on). This made the omapdss driver work as the top level DSS platform device and the rest had a parent-child relationship. This ensured that the parent hwmod("dss_core") is enabled if any of the children hwmods are enabled while using omapdss. This method, however, doesn't work when each hwmod is enabled individually. This happens early in boot in omap_hwmod_setup_all, where each hwmod is enabled, and then reset and idled. All the 'children' DSS hwmods fail to enable and reset, since they don't enable modulemode. The way to make such modules work both during initialization and when used by pm runtime API in the driver would be to add refcounting for enabling/disabling the modulemode field. We add a new flag bit for the flag in omap_hwmod_omap4_prcm, which tells omap_hwmod that this hwmod uses a modulemode field shared by other hwmods. We create a struct called 'modulemode_shared'. The hwmod data file should define a static instance of this struct. Each hwmod that uses this modulemode field should hold a pointer to this instance. omap_hwmod's soc enable_module and disable_module ops set the MODULEMODE reigster bits only when the first module using it is enabled, or the last module using it is disabled. We serialize accesses to the struct with a spinlock. Signed-off-by: Archit Taneja <archit@ti.com> --- arch/arm/mach-omap2/omap_hwmod.c | 123 +++++++++++++++++++++++++++++++++------ arch/arm/mach-omap2/omap_hwmod.h | 38 +++++++++--- 2 files changed, 133 insertions(+), 28 deletions(-)