05d8af449d
The current EOI handler for LEVEL triggered interrupts calls clk_enable(),
register IO, clk_disable(). The clock manipulation requires locking which
happens with IRQs disabled in clk_enable_lock(). Instead of turning the
clock on and off all the time, enable the clock in case LEVEL interrupt is
requested and keep the clock enabled until all LEVEL interrupts are freed.
The LEVEL interrupts are an exception on this platform and seldom used, so
this does not affect the common case.
This simplifies the LEVEL interrupt handling considerably and also fixes
the following splat found when using preempt-rt:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/locking/rtmutex.c:2040 __rt_mutex_trylock+0x37/0x62
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.109-rt65-stable-standard-00068-g6a5afc4b1217 #85
Hardware name: STM32 (Device Tree Support)
[<c010a45d>] (unwind_backtrace) from [<c010766f>] (show_stack+0xb/0xc)
[<c010766f>] (show_stack) from [<c06353ab>] (dump_stack+0x6f/0x84)
[<c06353ab>] (dump_stack) from [<c01145e3>] (__warn+0x7f/0xa4)
[<c01145e3>] (__warn) from [<c063386f>] (warn_slowpath_fmt+0x3b/0x74)
[<c063386f>] (warn_slowpath_fmt) from [<c063b43d>] (__rt_mutex_trylock+0x37/0x62)
[<c063b43d>] (__rt_mutex_trylock) from [<c063c053>] (rt_spin_trylock+0x7/0x16)
[<c063c053>] (rt_spin_trylock) from [<c036a2f3>] (clk_enable_lock+0xb/0x80)
[<c036a2f3>] (clk_enable_lock) from [<c036ba69>] (clk_core_enable_lock+0x9/0x18)
[<c036ba69>] (clk_core_enable_lock) from [<c034e9f3>] (stm32_gpio_get+0x11/0x24)
[<c034e9f3>] (stm32_gpio_get) from [<c034ef43>] (stm32_gpio_irq_trigger+0x1f/0x48)
[<c034ef43>] (stm32_gpio_irq_trigger) from [<c014aa53>] (handle_fasteoi_irq+0x71/0xa8)
[<c014aa53>] (handle_fasteoi_irq) from [<c0147111>] (generic_handle_irq+0x19/0x22)
[<c0147111>] (generic_handle_irq) from [<c014752d>] (__handle_domain_irq+0x55/0x64)
[<c014752d>] (__handle_domain_irq) from [<c0346f13>] (gic_handle_irq+0x53/0x64)
[<c0346f13>] (gic_handle_irq) from [<c0100ba5>] (__irq_svc+0x65/0xc0)
Exception stack(0xc0e01f18 to 0xc0e01f60)
1f00: 0000300c 00000000
1f20: 0000300c c010ff01 00000000 00000000 c0e00000 c0e07714 00000001 c0e01f78
1f40: c0e07758 00000000 ef7cd0ff c0e01f68 c010554b c0105542 40000033 ffffffff
[<c0100ba5>] (__irq_svc) from [<c0105542>] (arch_cpu_idle+0xc/0x1e)
[<c0105542>] (arch_cpu_idle) from [<c063be95>] (default_idle_call+0x21/0x3c)
[<c063be95>] (default_idle_call) from [<c01324f7>] (do_idle+0xe3/0x1e4)
[<c01324f7>] (do_idle) from [<c01327b3>] (cpu_startup_entry+0x13/0x14)
[<c01327b3>] (cpu_startup_entry) from [<c0a00c13>] (start_kernel+0x397/0x3d4)
[<c0a00c13>] (start_kernel) from [<00000000>] (0x0)
---[ end trace 0000000000000002 ]---
Power consumption measured on STM32MP157C DHCOM SoM is not increased or
is below noise threshold.
Fixes:
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.