The 'pwrdm_for_each()' function walks powerdomains with a spinlock
locked, so the the callbacks cannot do anything which may sleep.
This patch introduces a 'pwrdm_for_each_nolock()' helper which does
the same, but without the spinlock locked. This fixes the following
lockdep warning:
[ 0.000000] WARNING: at kernel/lockdep.c:2460 lockdep_trace_alloc+0xac/0xec()
[ 0.000000] Modules linked in:
(unwind_backtrace+0x0/0xdc) from [<c0045464>] (warn_slowpath_common+0x48/0x60)
(warn_slowpath_common+0x48/0x60) from [<c0067dd4>] (lockdep_trace_alloc+0xac/0xec)
(lockdep_trace_alloc+0xac/0xec) from [<c009da14>] (kmem_cache_alloc+0x1c/0xd0)
(kmem_cache_alloc+0x1c/0xd0) from [<c00b21d8>] (d_alloc+0x1c/0x1a4)
(d_alloc+0x1c/0x1a4) from [<c00a887c>] (__lookup_hash+0xd8/0x118)
(__lookup_hash+0xd8/0x118) from [<c00a9f20>] (lookup_one_len+0x84/0x94)
(lookup_one_len+0x84/0x94) from [<c010d12c>] (debugfs_create_file+0x8c/0x20c)
(debugfs_create_file+0x8c/0x20c) from [<c010d320>] (debugfs_create_dir+0x1c/0x20)
(debugfs_create_dir+0x1c/0x20) from [<c000e8cc>] (pwrdms_setup+0x60/0x90)
(pwrdms_setup+0x60/0x90) from [<c002e010>] (pwrdm_for_each+0x30/0x80)
(pwrdm_for_each+0x30/0x80) from [<c000e79c>] (pm_dbg_init+0x7c/0x14c)
(pm_dbg_init+0x7c/0x14c) from [<c00232b4>] (do_one_initcall+0x5c/0x1b8)
(do_one_initcall+0x5c/0x1b8) from [<c00083f8>] (kernel_init+0x90/0x10c)
(kernel_init+0x90/0x10c) from [<c00242c4>] (kernel_thread_exit+0x0/0x8)
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
At the end of the list pd is a pointer to a NULL struct, so checking
if the address == NULL doesn't help here. In fact the original code
will just keep running past the struct to read who knows what in
memory.
This case manifests itself when from clkdms_setup() when enabling auto
idle for a clock domain and the clockdomain usecount is greater than
0. When _clkdm_add_autodeps() tries to add the a dependency that does
not exist in the powerdomain->wkdep_srcs array the for loop will run
past the wkdep_srcs array.
Currently in linux-omap you won't hit this because the not found case
is never executed, unless you start modifying powerdomains and their
wakeup/sleep deps.
Signed-off-by: Mike Chan <mike@android.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Make the powerdomain code call the new hook for updating the time.
Also implement the updated pwrdm_for_each.
Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
This patch provides the infrastructure to count how many times a
powerdomain entered a given power state (on, inactive, retention,
off). A number of functions are provided which will be called by the
chip specific powerdomain and clockdomain code whenever a transition
might have happened.
Signed-off-by: Peter 'p2' De Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
with while (i++ < MAX_CLOCK_ENABLE_WAIT); i can reach MAX_CLOCK_ENABLE_WAIT + 1
after the loop, so if (i == MAX_CLOCK_ENABLE_WAIT) that's still success.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
OMAP3430ES2+ introduces a new feature: optional powerdomain context
hardware save-and-restore (SAR). Currently, this feature only applies
to USBHOST and USBTLL module context when the USBHOST or CORE
powerdomains enter a low-power sleep state[1]. This feature avoids
re-enumeration of USB devices when the powerdomains return from idle,
which is potentially time-consuming.
This patch adds support for enabling and disabling hardware
save-and-restore to the powerdomain code. Three new functions are
added, pwrdm_enable_hdwr_sar(), pwrdm_disable_hdwr_sar(), and
pwrdm_can_hdwr_sar(). A new struct powerdomain "flags" field is
added, with a PWRDM_HAS_HDWR_SAR flag to indicate powerdomains with
SAR support.
Thanks to Jouni Högander <jouni.hogander@nokia.com> for reviewing an
earlier version of these patches, and Richard Woodruff <r-woodruff2@ti.com>
for clarifying the purpose of these bits.
1. For the USBHOST controller module, context loss occurs when the
USBHOST powerdomain enters off-idle. For USBTLL, context loss
occurs either if CORE enters off-idle, or if the CORE logic is
configured to turn off when CORE enters retention-idle (OSWR).
34xx ES2 TRM 4.8.6.1.1, 4.8.6.1.2
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Thie patch adds code to the powerdomain layer to track the
clockdomains associated with each powerdomain.
It also modifies the clockdomain code to register clockdomains
with their corresponding powerdomain when the clockdomain is registered.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
This patch creates an interface to the powerdomain registers in the
PRM/CM modules on OMAP2/3. This interface is intended to be used by
PM code, e.g., pm.c; not by device drivers directly.
Each powerdomain will be defined in later patches as static
structures. Also defined are dependencies between powerdomains,
used for adding and removing PM_WKDEP and CM_SLEEPDEP bits. The
powerdomain structures are linked into a list at boot by
pwrdm_register(), similar to the OMAP clock code.
The patch adds a Kconfig option, CONFIG_OMAP_DEBUG_POWERDOMAIN, which
when enabled will emit verbose debug messages via pr_debug().
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
