powerpc/6xx: set High BAT Enable flag on G2_LE cores

MMU_FTR_USE_HIGH_BATS is set for G2_LE cores and derivatives like e300cX,
but the high BATs need to be enabled in HID2 to work. Add register
definitions and add the needed setup to __setup_cpu_603.

This fixes boot on CPUs like the MPC5200B with STRICT_KERNEL_RWX enabled
on systems where the flag has not been set by the bootloader already.

Fixes: e4d6654ebe6e ("powerpc/mm/32s: rework mmu_mapin_ram()")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240124103838.43675-1-matthias.schiffer@ew.tq-group.com

powerpc/32: Fix objtool unannotated intra-function call warnings

Fix several annotations in assembly files on PPC32.

[Sathvika Vasireddy: Changed subject line and removed Kconfig change to
enable objtool, as it is a part of "objtool/powerpc: Enable objtool to
be built on ppc" patch in this series.]

Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221114175754.1131267-7-sv@linux.ibm.com

powerpc/32: Blacklist functions running with MMU disabled for kprobe

kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3bf57066d05518644dee0840af69d36ab5086729.1585670437.git.christophe.leroy@c-s.fr

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 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 as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

powerpc/6xx: fix setup and use of SPRN_SPRG_PGDIR for hash32

Not only the 603 but all 6xx need SPRN_SPRG_PGDIR to be initialised at
startup. This patch move it from __setup_cpu_603() to start_here()
and __secondary_start(), close to the initialisation of SPRN_THREAD.

Previously, virt addr of PGDIR was retrieved from thread struct.
Now that it is the phys addr which is stored in SPRN_SPRG_PGDIR,
hash_page() shall not convert it to phys anymore.
This patch removes the conversion.

Fixes: 93c4a162b014 ("powerpc/6xx: Store PGDIR physical address in a SPRG")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/6xx: Store PGDIR physical address in a SPRG

Use SPRN_SPRG2 to store the current thread PGDIR and
avoid reading thread_struct.pgdir at every TLB miss.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: change CONFIG_6xx to CONFIG_PPC_BOOK3S_32

Today we have:

config PPC_BOOK3S_32
bool "512x/52xx/6xx/7xx/74xx/82xx/83xx/86xx"
[depends on PPC32 within a choice]

config PPC_BOOK3S
def_bool y
depends on PPC_BOOK3S_32 || PPC_BOOK3S_64

config 6xx
def_bool y
depends on PPC32 && PPC_BOOK3S

6xx is therefore redundant with PPC_BOOK3S_32.

In order to make the code clearer, lets use preferably PPC_BOOK3S_32.
This will allow to remove CONFIG_6xx in a later patch.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: clean inclusions of asm/feature-fixups.h

files not using feature fixup don't need asm/feature-fixups.h
files using feature fixup need asm/feature-fixups.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Free up CPU feature bits on 64-bit machines

This moves all the CPU feature bits that are only used on 32-bit
machines to the top 20 bits of the CPU feature word and arranges
for them to be defined only in 32-bit builds. The features that
are common to 32-bit and 64-bit machines are moved to bits 0-11
of the CPU feature word. This means that for 64-bit platforms,
bits 44-63 can now be used for new features that only exist on
64-bit machines. (These bit numbers are counting from the right,
i.e. the LSB is bit 0.)

Because CPU_FTR_L3_DISABLE_NAP moved from the low 16 bits to the high
16 bits, we have to adjust some assembly code. Also, CPU_FTR_EMB_HV
moved from the high 16 bits to the low 16 bits.

Note that CPU_FTR_REAL_LE only applies to 64-bit chips, because only
64-bit chips (POWER6, 7, 8, 9) have a true little-endian mode that is
a CPU execution mode as opposed to being a page attribute.

With this we now have 20 free CPU feature bits on 64-bit machines.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Various typo fixes

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Fix some 6xx/7xxx CPU setup functions

Some of those functions try to adjust the CPU features, for example
to remove NAP support on some revisions. However, they seem to use
r5 as an index into the CPU table entry, which might have been right
a long time ago but no longer is. r4 is the right register to use.

This probably caused some off behaviours on some PowerMac variants
using 750cx or 7455 processor revisions.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@kernel.org

powerpc: Use names rather than numbers for SPRGs (v2)

The kernel uses SPRG registers for various purposes, typically in
low level assembly code as scratch registers or to hold per-cpu
global infos such as the PACA or the current thread_info pointer.

We want to be able to easily shuffle the usage of those registers
as some implementations have specific constraints realted to some
of them, for example, some have userspace readable aliases, etc..
and the current choice isn't always the best.

This patch should not change any code generation, and replaces the
usage of SPRN_SPRGn everywhere in the kernel with a named replacement
and adds documentation next to the definition of the names as to
what those are used for on each processor family.

The only parts that still use the original numbers are bits of KVM
or suspend/resume code that just blindly needs to save/restore all
the SPRGs.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Enable additional BAT registers in setup_745x_specifics()

Currently the kernel expects the additional four IBAT and DBAT registers
to be available, but doesn't enable these registers on 745x CPUs, which
have them disabled after reset. Thus set the HIGH_BAT_EN bit in HID0
register, if the corresponding MMU feature is defined.

Signed-off-by: Gerhard Pircher <gerhard_pircher@gmx.net>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

powerpc/mm: e300c2/c3/c4 TLB errata workaround

Complete workaround for DTLB errata in e300c2/c3/c4 processors.

Due to the bug, the hardware-implemented LRU algorythm always goes to way
1 of the TLB. This fix implements the proposed software workaround in
form of a LRW table for chosing the TLB-way.

Based on patch from David Jander <david@protonic.nl>

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

[POWERPC] ppc32: Fix errata for 603 CPUs

603 CPUs have the same issue that some 750 CPUs have in that they can crash
in funny ways if a store from an FPU register instruction is executed on a
register that has never been initialized since power on. This patch fixes
it by making sure all FP registers have been properly initialized at kernel
boot.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

Spelling fix: explicitly

From: Jean Delvare <khali@linux-fr.org>

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[POWERPC] Guard L3CR references with CPU_FTR_L3CR.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

powerpc: Move cpu_setup_6xx.S and temp.c over to arch/powerpc

Also renamed temp.c to tau_6xx.c (for thermal assist unit) and updated
the Kconfig option description and help text for CONFIG_TAU.

Signed-off-by: Paul Mackerras <paulus@samba.org>