Commit Graph

32 Commits

Author SHA1 Message Date
7232398abc ARM: tegra: Convert PMC to a driver
This commit converts the PMC support code to a platform driver. Because
the boot process needs to call into this driver very early, also set up
a minimal environment via an early initcall.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-07-17 14:58:43 +02:00
304664eab9 ARM: tegra: Use a function to get the chip ID
Instead of using a simple variable access to get at the Tegra chip ID,
use a function so that we can run additional code. This can be used to
determine where the chip ID is being accessed without being available.
That in turn will be handy for resolving boot sequence dependencies in
order to convert more code to regular initcalls rather than a sequence
fixed by Tegra SoC setup code.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-07-17 13:36:41 +02:00
a0524acc94 ARM: tegra: Sort includes alphabetically
If these aren't sorted alphabetically, then the logical choice is to
append new ones, however that creates a lot of potential for conflicts
because every change will then add new includes in the same location.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-07-17 13:29:57 +02:00
1ff6bbfd13 arm, pm, vmpressure: add missing slab.h includes
arch/arm/mach-tegra/pm.c, kernel/power/console.c and mm/vmpressure.c
were somehow getting slab.h indirectly through cgroup.h which in turn
was getting it indirectly through xattr.h.  A scheduled cgroup change
drops xattr.h inclusion from cgroup.h and breaks compilation of these
three files.  Add explicit slab.h includes to the three files.

A pending cgroup patch depends on this change and it'd be great if
this can be routed through cgroup/for-3.14-fixes branch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-tegra@vger.kernel.org
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: cgroups@vger.kernel.org
2014-02-03 13:24:01 -05:00
f0c4ac1329 ARM: tegra: add LP1 support code for Tegra124
The LP1 suspend procedure is the same with Tegra30 and Tegra114. Just
need to update the difference of the register address, then we can
continue to share the code.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-10-18 16:28:10 -06:00
fddb770dbe ARM: tegra: move resume vector define to irammap.h
irammap.h's purpose is to define the layout/usage of IRAM. As such,
TEGRA_IRAM_CODE_AREA should have been added there rather than iomap.h.
Move the define, and rename it something more descriptive.

Cc: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-09-17 13:44:22 -06:00
bfa664f21b Merge tag 'tegra-for-3.12-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/soc
From: Stephen Warren:
ARM: tegra: core SoC enhancements for 3.12

This branch includes a number of enhancements to core SoC support for
Tegra devices. The major new features are:

* Adds a new CPU-power-gated cpuidle state for Tegra114.
* Adds initial system suspend support for Tegra114, initially supporting
  just CPU-power-gating during suspend.
* Adds "LP1" suspend mode support for all of Tegra20/30/114. This mode
  both gates CPU power, and places the DRAM into self-refresh mode.
* A new DT-driven PCIe driver to Tegra20/30. The driver is also moved
  from arch/arm/mach-tegra/ to drivers/pci/host/.

The PCIe driver work depends on the following tag from Thomas Petazzoni:
git://git.infradead.org/linux-mvebu.git mis-3.12.2
... which is merged into the middle of this pull request.

* tag 'tegra-for-3.12-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: (33 commits)
  ARM: tegra: disable LP2 cpuidle state if PCIe is enabled
  MAINTAINERS: Add myself as Tegra PCIe maintainer
  PCI: tegra: set up PADS_REFCLK_CFG1
  PCI: tegra: Add Tegra 30 PCIe support
  PCI: tegra: Move PCIe driver to drivers/pci/host
  PCI: msi: add default MSI operations for !HAVE_GENERIC_HARDIRQS platforms
  ARM: tegra: add LP1 suspend support for Tegra114
  ARM: tegra: add LP1 suspend support for Tegra20
  ARM: tegra: add LP1 suspend support for Tegra30
  ARM: tegra: add common LP1 suspend support
  clk: tegra114: add LP1 suspend/resume support
  ARM: tegra: config the polarity of the request of sys clock
  ARM: tegra: add common resume handling code for LP1 resuming
  ARM: pci: add ->add_bus() and ->remove_bus() hooks to hw_pci
  of: pci: add registry of MSI chips
  PCI: Introduce new MSI chip infrastructure
  PCI: remove ARCH_SUPPORTS_MSI kconfig option
  PCI: use weak functions for MSI arch-specific functions
  ARM: tegra: unify Tegra's Kconfig a bit more
  ARM: tegra: remove the limitation that Tegra114 can't support suspend
  ...

Signed-off-by: Kevin Hilman <khilman@linaro.org>
2013-08-21 10:17:18 -07:00
e9f624499c ARM: tegra: add LP1 suspend support for Tegra114
The LP1 suspend mode will power off the CPU, clock gated the PLLs and put
SDRAM to self-refresh mode. Any interrupt can wake up device from LP1. The
sequence when LP1 suspending:

* tunning off L1 data cache and the MMU
* storing some EMC registers, DPD (deep power down) status, clk source of
  mselect and SCLK burst policy
* putting SDRAM into self-refresh
* switching CPU to CLK_M (12MHz OSC)
* tunning off PLLM, PLLP, PLLA, PLLC and PLLX
* switching SCLK to CLK_S (32KHz OSC)
* shutting off the CPU rail

The sequence of LP1 resuming:

* re-enabling PLLM, PLLP, PLLA, PLLC and PLLX
* restoring the clk source of mselect and SCLK burst policy
* setting up CCLK burst policy to PLLX
* restoring DPD status and some EMC registers
* resuming SDRAM to normal mode
* jumping to the "tegra_resume" from PMC_SCRATCH41

Due to the SDRAM will be put into self-refresh mode, the low level
procedures of LP1 suspending and resuming should be copied to
TEGRA_IRAM_CODE_AREA (TEGRA_IRAM_BASE + SZ_4K) when suspending. Before
restoring the CPU context when resuming, the SDRAM needs to be switched
back to normal mode. And the PLLs need to be re-enabled, SCLK burst policy
be restored. Then jumping to "tegra_resume" that was expected to be stored
in PMC_SCRATCH41 to restore CPU context and back to kernel.

Based on the work by: Bo Yan <byan@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-08-12 13:30:12 -06:00
731a927438 ARM: tegra: add LP1 suspend support for Tegra20
The LP1 suspend mode will power off the CPU, clock gated the PLLs and put
SDRAM to self-refresh mode. Any interrupt can wake up device from LP1. The
sequence when LP1 suspending:

* tunning off L1 data cache and the MMU
* putting SDRAM into self-refresh
* storing some EMC registers and SCLK burst policy
* switching CPU to CLK_M (12MHz OSC)
* switching SCLK to CLK_S (32KHz OSC)
* tunning off PLLM, PLLP and PLLC
* shutting off the CPU rail

The sequence of LP1 resuming:

* re-enabling PLLM, PLLP, and PLLC
* restoring some EMC registers and SCLK burst policy
* setting up CCLK burst policy to PLLP
* resuming SDRAM to normal mode
* jumping to the "tegra_resume" from PMC_SCRATCH41

Due to the SDRAM will be put into self-refresh mode, the low level
procedures of LP1 suspending and resuming should be copied to
TEGRA_IRAM_CODE_AREA (TEGRA_IRAM_BASE + SZ_4K) when suspending. Before
restoring the CPU context when resuming, the SDRAM needs to be switched
back to normal mode. And the PLLs need to be re-enabled, SCLK burst policy
be restored, CCLK burst policy be set in PLLP. Then jumping to
"tegra_resume" that was expected to be stored in PMC_SCRATCH41 to restore
CPU context and back to kernel.

Based on the work by:
Colin Cross <ccross@android.com>
Gary King <gking@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-08-12 13:30:11 -06:00
e7a932b196 ARM: tegra: add LP1 suspend support for Tegra30
The LP1 suspend mode will power off the CPU, clock gated the PLLs and put
SDRAM to self-refresh mode. Any interrupt can wake up device from LP1. The
sequence when LP1 suspending:

* tunning off L1 data cache and the MMU
* storing some EMC registers, DPD (deep power down) status, clk source of
  mselect and SCLK burst policy
* putting SDRAM into self-refresh
* switching CPU to CLK_M (12MHz OSC)
* tunning off PLLM, PLLP, PLLA, PLLC and PLLX
* switching SCLK to CLK_S (32KHz OSC)
* shutting off the CPU rail

The sequence of LP1 resuming:

* re-enabling PLLM, PLLP, PLLA, PLLC and PLLX
* restoring the clk source of mselect and SCLK burst policy
* setting up CCLK burst policy to PLLX
* restoring DPD status and some EMC registers
* resuming SDRAM to normal mode
* jumping to the "tegra_resume" from PMC_SCRATCH41

Due to the SDRAM will be put into self-refresh mode, the low level
procedures of LP1 suspending and resuming should be copied to
TEGRA_IRAM_CODE_AREA (TEGRA_IRAM_BASE + SZ_4K) when suspending. Before
restoring the CPU context when resuming, the SDRAM needs to be switched
back to normal mode. And the PLLs need to be re-enabled, SCLK burst policy
be restored, CCLK burst policy be set in PLLX. Then jumping to
"tegra_resume" that was expected to be stored in PMC_SCRATCH41 to restore
CPU context and back to kernel.

Based on the work by: Scott Williams <scwilliams@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-08-12 13:30:11 -06:00
95872f427e ARM: tegra: add common LP1 suspend support
The LP1 suspending mode on Tegra means CPU rail off, devices and PLLs are
clock gated and SDRAM in self-refresh mode. That means the low level LP1
suspending and resuming code couldn't be run on DRAM and the CPU must
switch to the always on clock domain (a.k.a. CLK_M 12MHz oscillator). And
the system clock (SCLK) would be switched to CLK_S, a 32KHz oscillator.
The LP1 low level handling code need to be moved to IRAM area first. And
marking the LP1 mask for indicating the Tegra device is in LP1. The CPU
power timer needs to be re-calculated based on 32KHz that was originally
based on PCLK.

When resuming from LP1, the LP1 reset handler will resume PLLs and then
put DRAM to normal mode. Then jumping to the "tegra_resume" that will
restore full context before back to kernel. The "tegra_resume" handler
was expected to be found in PMC_SCRATCH41 register.

This is common LP1 procedures for Tegra, so we do these jobs mainly in
this patch:
* moving LP1 low level handling code to IRAM
* marking LP1 mask
* copying the physical address of "tegra_resume" to PMC_SCRATCH41
* re-calculate the CPU power timer based on 32KHz

Signed-off-by: Joseph Lo <josephl@nvidia.com>
[swarren, replaced IRAM_CODE macro with IO_ADDRESS(TEGRA_IRAM_CODE_AREA)]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-08-12 13:29:24 -06:00
9c0c4b43b1 ARM: tegra: remove the limitation that Tegra114 can't support suspend
The Tegra114 can support suspend function now, removing the limitation.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-07-19 10:08:09 -06:00
b573ad9f19 ARM: tegra: hook tegra_tear_down_cpu function
Hooking tegra_tear_down_cpu for Tegra114 for supporting cluster power
down when CPU cluster suspneded in LP2.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-07-19 10:08:07 -06:00
8bd26e3a7e arm: delete __cpuinit/__CPUINIT usage from all ARM users
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
and are flagged as __cpuinit  -- so if we remove the __cpuinit from
the arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
related content into no-ops as early as possible, since that will get
rid of these warnings.  In any case, they are temporary and harmless.

This removes all the ARM uses of the __cpuinit macros from C code,
and all __CPUINIT from assembly code.  It also had two ".previous"
section statements that were paired off against __CPUINIT
(aka .section ".cpuinit.text") that also get removed here.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:52 -04:00
8f6a0b6528 ARM: tegra: don't pass CPU ID to tegra_{set,clear}_cpu_in_lp2
tegra_{set,clear}_cpu_in_lp2 can easily determine which CPU ID they are
running on; there is no need to pass the CPU ID into those functions.
So, remove their CPU ID function parameter.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-06-05 11:44:58 -06:00
bf91add4a0 ARM: tegra: hook tegra_tear_down_cpu function in the PM suspend init function
The tegra_tear_down_cpu was used to cut off the CPU rail for various Tegra
SoCs. Hooking it in the PM suspend init function and making the CPUidle
driver more generic.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-06-05 11:44:54 -06:00
97b1007a29 Merge tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC platform updates from Olof Johansson:
 "This branch contains part 1 of the platform updates for 3.10.  Among
  the highlights:

   - Support for the new Atmel Cortex-A5 based platforms (SAMA5D3)
   - New support for CSR SiRFatlas6 SoCs
   - A handful of updates for NVidia T114 (a.k.a. Tegra 4)
   - A bunch of updates for the shmobile platforms
   - A handful of updates for davinci
   - A few updates for Qualcomm MSM
   - Plus a handful of other patches, defconfig updates, etc."

* tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (135 commits)
  ARM: tegra: pm: fix build error w/o PM_SLEEP
  ARM: davinci: ensure global variables are declared
  ARM: davinci: sram.c: fix incorrect type in assignment
  ARM: davinci: da8xx dt: make file local symbols static
  ARM: davinci: da8xx: add remoteproc support
  ARM: socfpga: Upgrade clk driver for socfpga to make use of dts clock entries
  ARM: socfpga: Add clock entries into device tree
  ARM: socfpga: Enable soft reset
  ARM: EXYNOS: replace cpumask by the corresponding macro
  ARM: EXYNOS: handle properly the return values
  ARM: EXYNOS: factor out the idle states
  ARM: OMAP4: Enable fix for Cortex-A9 erratas
  ARM: OMAP2+: Export SoC information to userspace
  ARM: OMAP2+: SoC name and revision unification
  ARM: OMAP2+: Move common part of late init into common function
  ARM: tegra: pm: remove duplicated include from pm.c
  ARM: davinci: da850: override mmc DT node device name
  ARM: davinci: da850: add mmc DT entries
  mmc: davinci_mmc: add DT support
  ARM: SAMSUNG: check processor type before cache restoration in resume
  ...
2013-05-02 09:31:45 -07:00
a7726350e0 Merge tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanup from Olof Johansson:
 "Here is a collection of cleanup patches.  Among the pieces that stand
  out are:

   - The deletion of h720x platforms
   - Split of at91 non-dt platforms to their own Kconfig file to keep
     them separate
   - General cleanups and refactoring of i.MX and MXS platforms
   - Some restructuring of clock tables for OMAP
   - Convertion of PMC driver for Tegra to dt-only
   - Some renames of sunxi -> sun4i (Allwinner A10)
   - ... plus a bunch of other stuff that I haven't mentioned"

* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (119 commits)
  ARM: i.MX: remove unused ARCH_* configs
  ARM i.MX53: remove platform ahci support
  ARM: sunxi: Rework the restart code
  irqchip: sunxi: Rename sunxi to sun4i
  irqchip: sunxi: Make use of the IRQCHIP_DECLARE macro
  clocksource: sunxi: Rename sunxi to sun4i
  clocksource: sunxi: make use of CLKSRC_OF
  clocksource: sunxi: Cleanup the timer code
  ARM: at91: remove trailing semicolon from macros
  ARM: at91/setup: fix trivial typos
  ARM: EXYNOS: remove "config EXYNOS_DEV_DRM"
  ARM: EXYNOS: change the name of USB ohci header
  ARM: SAMSUNG: Remove unnecessary code for dma
  ARM: S3C24XX: Remove unused GPIO drive strength register definitions
  ARM: OMAP4+: PM: Restore CPU power state to ON with clockdomain force wakeup method
  ARM: S3C24XX: Removed unneeded dependency on CPU_S3C2412
  ARM: S3C24XX: Removed unneeded dependency on CPU_S3C2410
  ARM: S3C24XX: Removed unneeded dependency on ARCH_S3C24XX for boards
  ARM: SAMSUNG: Fix typo "CONFIG_SAMSUNG_DEV_RTC"
  ARM: S5P64X0: Fix typo "CONFIG_S5P64X0_SETUP_SDHCI"
  ...
2013-05-02 09:03:55 -07:00
2058842e6d ARM: tegra: call cpu_do_idle from C code
When building a kernel for multiple CPU architecture levels,
cpu_do_idle() is a macro for an indirect function call, which
cannot be called from assembly code as Tegra does.

Adding a trivial C wrapper for this function lets us build
a tegra kernel with ARMv6 support enabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Joseph Lo <josephl@nvidia.com>
Cc: Stephen Warren <swarren@nvidia.com>
2013-04-29 16:51:59 +02:00
6cd2f8e7da Merge tag 'tegra-for-3.10-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/soc
From Stephen Warren <swarren@wwwdotorg.org>:

ARM: tegra: core SoC support development

This branch includes major development on the core Tegra SoC support code
in the mach-tegra directory:

* SMP support for Tegra114.
* Exposes SoC chip ID and revision through standard sysfs files.
* System-level suspend/resume for Tegra20/30. At present, this only
  supports "LP2" mode (CPU power-down), but provides the basis to
  implement "LP0"/"LP1" (various levels of core/chip power-down) in the
  hopefully near future.
* A minor cleanup of a duplicate include, which was introduced in this
  branch.

This branch is based on the previous cleanup pull request.

* tag 'tegra-for-3.10-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra:
  ARM: tegra: pm: remove duplicated include from pm.c
  ARM: tegra: cpuidle: remove redundant parameters for powered-down mode
  ARM: tegra: pm: add platform suspend support
  ARM: dt: tegra: add bindings of power management configurations for PMC
  ARM: tegra: irq: add wake up handling
  gpio: tegra: add gpio wakeup source handling
  ARM: tegra: moving the CPU power timer function to PMC driver
  ARM: tegra: add clock source of PMC to device trees
  ARM: tegra: add speedo-based process id for Tegra114
  ARM: tegra: expose chip ID and revision
  ARM: tegra: bring up secondary CPU for Tegra114

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2013-04-09 16:32:20 +02:00
38be85de69 ARM: tegra: pm: remove duplicated include from pm.c
Remove duplicated include.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-04-05 09:40:17 -06:00
4d82d0587b ARM: tegra: cpuidle: remove redundant parameters for powered-down mode
After the patch series for system suspending support, tegra_idle_lp2_last()
no longer uses its parameters cpu_on_time or cpu_off_time, so remove them.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-04-03 14:45:42 -06:00
c8c2e60690 ARM: tegra: pm: add platform suspend support
Adding suspend to RAM support for Tegra platform. There are three suspend
mode for Tegra. The difference were below.

* LP2: CPU voltage off
* LP1: CPU voltage off, DRAM in self-refresh
* LP0: CPU + Core voltage off, DRAM in self-refresh

After this patch, the LP2 suspend mode will be supported.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-04-03 14:31:41 -06:00
0337c3e0c3 ARM: tegra: moving the CPU power timer function to PMC driver
The CPU power timer set up function was related to PMC register. Now moving
it to PMC driver. And it also help to clean up the PM related code later.

The timer was calculated based on the input clock of PMC. In this patch, we
also get the clock from DT.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-04-03 14:30:22 -06:00
6affb48264 ARM: tegra: use setup_mm_for_reboot rather than explicit pgd switch
This patch changes the Tegra PM code to use the setup_mm_for_reboot
helper rather than call cpu_switch_mm directly. This keeps things like
TLB invalidation in one place.

Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-03-26 14:30:41 -06:00
02e75d6488 ARM: tegra: remove save/restore of CPU diag register
Prior to this change, {save,restore}_cpu_arch_register() collaborated to
maintain the value of the CPU diagnostic register across power cycles.
This was required to maintain any CPU errata workaround enable bits in
that register. However, now that the Tegra reset vector code always
enables all required workarounds, there is no need to save and restore
the diagnostic register; it is always explicitly programmed in the
required manner.

Hence, remove the save/restore logic.

This has the advantage that the kernel always directly controls the value
of this register every boot, rather than relying on a bootloader or other
kernel code having previously written the correct value into it. This
makes CPU0 (which was previously saved/restored) and CPUn (which should
have been set up by the reset vector) be controlled in exactly the same
way, which is easier to debug/find/...

In particular, when converting Tegra to a multi-platform kernel, the CPU0
diagnostic register value initially comes from the bootloader. Most Tegra
bootloaders don't yet enable all required CPU bug workarounds. The
previous commit updates the kernel to do so on any CPU power cycle.
However, the save/restore code ends up over-writing the value with the
old bootloader-driven value instead of the now more-likely-to-be-correct
kernel value!

Even irrespective of multi-platform conversion, this change limits the
kernel's exposure to any WARs the bootloader didn't enable for CPU0: on
the very first LP2 transition (CPU power-saving which power-cycles the
CPU), the correct value will be enabled.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-03-11 14:29:22 -06:00
5c1350bdfc ARM: tegra20: cpuidle: add powered-down state for secondary CPU
The powered-down state of Tegra20 requires power gating both CPU cores.
When the secondary CPU requests to enter powered-down state, it saves
its own contexts and then enters WFI. The Tegra20 had a limition to
power down both CPU cores. The secondary CPU must waits for CPU0 in
powered-down state too. If the secondary CPU be woken up before CPU0
entering powered-down state, then it needs to restore its CPU states
and waits for next chance.

Be aware of that, you may see the legacy power state "LP2" in the code
which is exactly the same meaning of "CPU power down".

Based on the work by:
Colin Cross <ccross@android.com>
Gary King <gking@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-01-28 11:20:38 -07:00
89572c77cd ARM: tegra: move tegra_cpu_car.h to linux/clk/tegra.h
tegra_cpu_car_ops struct is going to be accessed from drivers/clk/tegra.
Move the tegra_cpu_car_ops to include/linux/clk/tegra.h.

Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-01-28 11:19:06 -07:00
8c627fa658 ARM: tegra: clean up the CPUINIT section
There are some redundant codes in the CPUINIT section that was caused by
some codes not be organized well in "headsmp.S". Currently all the codes
in "headsmp.S" were put into CPUINIT section. But actually it doesn't
need to be loacted in CPUINIT section. There is no fuction access them
in CPUINIT section and we will relocate them to IRAM.

These codes also caused some unnecessary functions that access these
codes been put into CPUINIT section too. This patch clean it up and put
them into normal text section.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2013-01-28 10:21:51 -07:00
29a0e7beab ARM: tegra: retain L2 content over CPU suspend/resume
The L2 RAM is in different power domain from the CPU cluster. So the
L2 content can be retained over CPU suspend/resume. To do that, we
need to disable L2 after the MMU is disabled, and enable L2 before
the MMU is enabled. But the L2 controller is in the same power domain
with the CPU cluster. We need to restore it's settings and re-enable
it after the power be resumed.

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2012-11-15 15:09:22 -07:00
d552920a02 ARM: tegra30: cpuidle: add powered-down state for CPU0
This is a power gating idle mode. It support power gating vdd_cpu rail
after all cpu cores in "powered-down" status. For Tegra30, the CPU0 can
enter this state only when all secondary CPU is offline. We need to take
care and make sure whole secondary CPUs were offline and checking the
CPU power gate status. After that, the CPU0 can go into "powered-down"
state safely. Then shut off the CPU rail.

Be aware of that, you may see the legacy power state "LP2" in the code
which is exactly the same meaning of "CPU power down".

Base on the work by:
Scott Williams <scwilliams@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2012-11-15 15:09:22 -07:00
d457ef358f ARM: tegra30: cpuidle: add powered-down state for secondary CPUs
This supports power-gated idle on secondary CPUs for Tegra30. The
secondary CPUs can go into powered-down state independently. When
CPU goes into this state, it saves it's contexts and puts itself
to flow controlled WFI state. After that, it will been power gated.

Be aware of that, you may see the legacy power state "LP2" in the
code which is exactly the same meaning of "CPU power down".

Based on the work by:
Scott Williams <scwilliams@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
2012-11-15 15:09:21 -07:00