Commit Graph

14 Commits

Author SHA1 Message Date
Ard Biesheuvel
4708fb0413 ARM: vfp: Reimplement VFP exception entry in C code
En/disabling softirqs from asm code turned out to be trickier than
expected, so vfp_support_entry now returns by tail calling
__local_enable_bh_ip() and passing the same arguments that a C call to
local_bh_enable() would pass. However, this is slightly hacky, as we
don't want to carry our own implementation of local_bh_enable().

So let's bite the bullet, and get rid of the asm logic in
vfp_support_entry that reasons about whether or not to save and/or
reload the VFP state, and about whether or not an FP exception is
pending, and only keep the VFP loading logic as a function that is
callable from C.

Replicate the removed logic in vfp_entry(), and use the exact same
reasoning as in the asm code. To emphasize the correspondence, retain
some of the asm comments in the C version as well.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
2023-05-17 15:08:14 +02:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Nicolas Pitre
a85b2257a5 ARM: 8629/1: vfp: properly tag assembly function declarations in C code
This is good for consistency even if there is no difference in compiled
code. LTO might rely on this eventually. No need to preserve the extern
attribute as it is the default with function prototypes.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-11-22 11:45:09 +00:00
Catalin Marinas
3d1228ead6 [ARM] 5387/1: Add ptrace VFP support on ARM
This patch adds ptrace support for setting and getting the VFP registers
using PTRACE_SETVFPREGS and PTRACE_GETVFPREGS. The user_vfp structure
defined in asm/user.h contains 32 double registers (to cover VFPv3 and
Neon hardware) and the FPSCR register.

Cc: Paul Brook <paul@codesourcery.com>
Cc: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-12 10:59:43 +00:00
Ben Dooks
fc0b7a2036 [ARM] 5349/1: VFP: Add PM code to save and restore current VFP state
When CONFIG_PM is selected, the VFP code does not have any handler
installed to deal with either saving the VFP state of the current
task, nor does it do anything to try and restore the VFP after a
resume.

On resume, the VFP will have been reset and the co-processor access
control registers are in an indeterminate state (very probably the
CP10 and CP11 the VFP uses will have been disabled by the ARM core
reset). When this happens, resume will break as soon as it tries to
unfreeze the tasks and restart scheduling.

Add a sys device to allow us to hook the suspend call to save the
current thread state if the thread is using VFP and a resume hook
which restores the CP10/CP11 access and ensures the VFP is disabled
so that the lazy swapping will take place on next access.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-12-18 21:21:34 +00:00
Catalin Marinas
25ebee020b [ARM] 4583/1: ARMv7: Add VFPv3 support
This patch adds the support for VFPv3 (the kernel currently supports
VFPv2). The main difference is 32 double registers (compared to 16).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-01-26 14:41:28 +00:00
Russell King
90e6b04836 [ARM] vfp: fix fuitod/fsitod instructions
These two instructions exceptionally take a single precision register
as their operand.  This means we can't use vfp_get_dm() to read the
register number - we need to use vfp_get_sm() instead.  Add a flag to
indicate this exception to the general rule.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-01-10 17:07:08 +00:00
Catalin Marinas
c642846489 [ARM] 4111/1: Allow VFP to work with thread migration on SMP
The current lazy saving of the VFP registers is no longer possible
with thread migration on SMP. This patch implements a per-CPU
vfp-state pointer and the saving of the VFP registers at every context
switch. The registers restoring is still performed in a lazy way.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-01-25 16:35:29 +00:00
Russell King
baf97ce6ed [ARM] Cleanups for 4cc9bd2eaa
- Document the meaning for OP_SCALAR, OP_SD and add OP_DD.
- Formatting cleanups
- Remove now redundant code for making compare instructions
  operate on scalar values.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-25 10:34:59 +01:00
Gen FUKATSU
4cc9bd2eaa [ARM] 3789/4: Fix VFP emulation to ignore VECITR for scalar instruction
VECITR in Floating-Point Exception register indicates the number of
remaining short vector iterations after a potential exception was
detected.

In case of exception caused by scalar instructions, VECITR is NOT updated.
Therefore emulation for VFP must ignore VECITR field
and treat "veclen" as zero when recognizing scalar instructing.

Signed-off-by: Gen Fukatsu <fukatsu.gen@jp.panasonic.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-25 10:34:06 +01:00
Daniel Jacobowitz
0355b3e039 [ARM] 3750/3: Fix double VFP emulation for EABI kernels
Patch from Daniel Jacobowitz

vfp_put_double didn't work in a CONFIG_AEABI kernel.  By swapping
the arguments, we arrange for them to be in the same place regardless
of ABI.  I made the same change to vfp_put_float for consistency.

Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-08-30 15:06:39 +01:00
Daniel Jacobowitz
7c6f25141b [ARM] 3748/3: Correct error check in vfp_raise_exceptions
Patch from Daniel Jacobowitz

The recent fix to hide VFP_NAN_FLAG broke the check in vfp_raise_exceptions;
it would attempt to deliver an exception mask of 0xfffffeff instead of reporting
a serious error condition using printk.  Define a safe constant to use for
an invalid exception maskm, and use it at both ends.

Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-08-27 12:42:08 +01:00
Russell King
438a761679 [PATCH] ARM: Fix VFP to use do_div()
VFP used __divdi3 64-bit division needlessly.  Convert it to use
our 64-bit by 32-bit division instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-29 23:01:02 +01:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00