for_each_child_of_node performs an of_node_get on each iteration, so no
of_node_get is needed on breaking out of the loop when the device_node
structure is saved in another variable.

A simplified semantic match that finds this problem is as follows
(http://coccinelle.lip6.fr):

// <smpl>
@@
expression root;
local idexpression child;
@@

 for_each_child_of_node(root, child) {
   ...
*  of_node_get(child)
   ...
   break;
 }
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Patchwork: https://patchwork.linux-mips.org/patch/11357/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add user-mode implementations of gettimeofday() and clock_gettime() to
the VDSO. This is currently usable with 2 clocksources: the CP0 count
register, which is accessible to user-mode via RDHWR on R2 and later
cores, or the MIPS Global Interrupt Controller (GIC) timer, which
provides a "user-mode visible" section containing a mirror of its
counter registers. This section must be mapped into user memory, which
is done below the VDSO data page.

When a supported clocksource is not in use, the VDSO functions will
return -ENOSYS, which causes libc to fall back on the standard syscall
path.

When support for neither of these clocksources is compiled into the
kernel at all, the VDSO still provides clock_gettime(), as the coarse
realtime/monotonic clocks can still be implemented. However,
gettimeofday() is not provided in this case as nothing can be done
without a suitable clocksource. This causes the symbol lookup to fail
in libc and it will then always use the standard syscall path.

This patch includes a workaround for a bug in QEMU which results in
RDHWR on the CP0 count register always returning a constant (incorrect)
value. A fix for this has been submitted, and the workaround can be
removed after the fix has been in stable releases for a reasonable
amount of time.

A simple performance test which calls gettimeofday() 1000 times in a
loop and calculates the average execution time gives the following
results on a Malta + I6400 (running at 20MHz):

 - Syscall:    ~31000 ns
 - VDSO (GIC): ~15000 ns
 - VDSO (CP0): ~9500 ns

[markos.chandras@imgtec.com:
- Minor code re-arrangements in order for mappings to be made
in the order they appear to the process' address space.
- Move do_{monotonic, realtime} outside of the MIPS_CLOCK_VSYSCALL ifdef
- Use gic_get_usm_range so we can do the GIC mapping in the
arch/mips/kernel/vdso instead of the GIC irqchip driver]
Signed-off-by: NAlex Smith <alex.smith@imgtec.com>
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11338/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Add an initial implementation of a proper (i.e. an ELF shared library)
VDSO. With this commit it does not export any symbols, it only replaces
the current signal return trampoline page. A later commit will add user
implementations of gettimeofday()/clock_gettime().

To support both new toolchains and old ones which don't generate ABI
flags section, we define its content manually and then use a tool
(genvdso) to patch up the section to have the correct name and type.
genvdso also extracts symbol offsets ({,rt_}sigreturn) needed by the
kernel, and generates a C file containing a "struct mips_vdso_image"
containing both the VDSO data and these offsets. This C file is
compiled into the kernel.

On 64-bit kernels we require a different VDSO for each supported ABI,
so we may build up to 3 different VDSOs. The VDSO to use is selected by
the mips_abi structure.

A kernel/user shared data page is created and mapped below the VDSO
image. This is currently empty, but will be used by the user time
function implementations which are added later.

[markos.chandras@imgtec.com:
- Add more comments
- Move abi detection in genvdso.h since it's the get_symbol function
that needs it.
- Add an R6 specific way to calculate the base address of VDSO in order
to avoid the branch instruction which affects performance.
- Do not patch .gnu.attributes since it's not needed for dynamic linking.
- Simplify Makefile a little bit.
- checkpatch fixes
- Restrict VDSO support for binutils < 2.25 for pre-R6
- Include atomic64.h for O32 variant on MIPS64]
Signed-off-by: NAlex Smith <alex.smith@imgtec.com>
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11337/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts mpc30x_defconfig to use libata PATA
drivers.

PS This platform still uses "ide0=base[,ctl[,irq]]" hack in
its defconfig.  The hack itself has been removed in 2008 and
this platform should be converted to using PATA platform host
driver (pata_platform) instead.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11141/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts maltaup_xpa_defconfig to use libata PATA
drivers (tc86c001 IDE host driver has no corresponding libata
driver yet so it is not converted).
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11140/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts maltaup_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11142/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts maltasmvp_eva_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11139/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts maltaaprp_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: b.zolnierkie@samsung.com
Patchwork: https://patchwork.linux-mips.org/patch/11137/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts malta_qemu_32r6_defconfig to use libata
PATA drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: b.zolnierkie@samsung.com
Patchwork: https://patchwork.linux-mips.org/patch/11138/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts malta_kvm_guest_defconfig to use libata
PATA drivers (tc86c001 IDE host driver has no corresponding
libata driver yet so it is not converted).
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Sanjay Lal <sanjayl@kymasys.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11136/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts malta_kvm_defconfig to use libata PATA
drivers (tc86c001 IDE host driver has no corresponding libata
driver yet so it is not converted).
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Sanjay Lal <sanjayl@kymasys.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11135/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts malta_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11134/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts lemote2f_defconfig to use libata PATA
drivers.

PS This platform uses CS5536 chipset which (due to historical
reasons) has basic support in AMD/nVidia PATA host driver and
full support in a newer CS5536 PATA one (pata_cs5536).  Thus
most likely this platform should switch to using the latter
host driver.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11133/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts lasat_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Brian Murphy <brian@murphy.dk>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11132/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts fuloong2e_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11131/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts e55_defconfig to use libata PATA drivers.

PS This platform still uses "ide0=base[,ctl[,irq]]" hack in
its defconfig.  The hack itself has been removed in 2008 and
this platform should be converted to using PATA platform host
driver (pata_platform) instead.

Cc: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts capcella_defconfig to use libata PATA
drivers.
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11129/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

IDE subsystem has been deprecated since 2009 and the majority
(if not all) of Linux distributions have switched to use
libata for ATA support exclusively.  However there are still
some users (mostly old or/and embedded non-x86 systems) that
have not converted from using IDE subsystem to libata PATA
drivers.  This doesn't seem to be good thing in the long-term
for Linux as while there is less and less PATA systems left
in use:

* testing efforts are divided between two subsystems

* having duplicate drivers for same hardware confuses users

This patch converts bigsur_defconfig to use libata PATA
drivers (tc86c001 IDE host driver has no corresponding libata
driver yet so it is not converted).
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: linux-mips@linux-mips.org
Cc: linux-ide@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11128/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Extend the existing support for Hardware Table Walking (HTW) to MIPS64
systems by supporting PMDs & setting the pointer size bit in PWSize,
then ceasing to blacklist HTW on MIPS64 systems.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11224/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

If we fail to register any real SMP implementations, fall back to
registering the dummy UP implementation. Otherwise when we build an SMP
kernel & run it on a system where the SMP implementations fail to probe
(eg. QEMU) the kernel will perform a NULL dereference attempting to call
mp_ops->smp_setup() from plat_smp_setup().

Notably this fixes booting kernels with CPS SMP enabled on QEMU, which
doesn't currently implement the CM, CPC or GIC.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Rob Herring <robh@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11223/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Move memory configuration to be performed via device tree for the Malta
board. This moves more Malta specific code to malta-dtshim.c, leaving
the rest of the mti-malta code a little more board-agnostic. This will
be useful to share more code between boards, with the device tree
providing the board specifics as intended.

Since we can't rely upon Malta boards running a bootloader capable of
handling devictrees & filling in the required information, a piece of
shim code (malta_dt_shim) is added to consume the (e)memsize variables
provided as part of the bootloader environment (or on the kernel command
line) then generate the DT memory node using the provided values.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Kumar Gala <galak@codeaurora.org>
Cc: linux-kernel@vger.kernel.org
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Patchwork: https://patchwork.linux-mips.org/patch/11222/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The fw_getmdesc function & fw_memblock_t abstraction is only used by
Malta, and so far as I can tell serves no purpose beyond making the code
less clear than it could be. Remove the useless level of abstraction.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11221/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Split the obj-y entries to their own lines such that it's easier to see
what's going on when adding or removing entries.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11220/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit a68d09a1 ("MIPS: Don't use RI/XI with 32-bit kernels on
64-bit CPUs") prevented use of RIXI on MIPS64 systems, stating that the
"TLB handlers cannot handle this case". What they actually couldn't
handle was cases where there were less fill bits in the Entry{Lo,Hi}
registers than bits used by software in PTEs. The handlers can now deal
with this case, so enable RIXI for MIPS32 kernels on MIPS64 systems.

Note that beyond the obvious benefits provided by having RIXI on such
systems, this is required for systems implementing MIPSr6 where RIXI
cannot be disabled.

This reverts commit a68d09a1 ("MIPS: Don't use RI/XI with 32-bit
kernels on 64-bit CPUs").
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11219/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit 748e787e ("MIPS: Optimize TLB refill for RI/XI
configurations.") stopped explicitly clearing the bits used by software
in PTEs by making use of a rotate instruction that rotates them into the
fill bits of the Entry{Lo,Hi} register. This can only work if there are
actually enough fill bits in the register to cover the software
maintained bits, otherwise we end up writing those bits into the upper
bits of the PFN or PFNX field of the Entry{Lo,Hi} register.

Fix this by detecting the number of fill bits present in the
Entry{Lo,Hi} registers & explicitly clearing the software bits where
necessary.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11218/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Tidy up the definition of the EntryLo RI & XI bits using BITS_PER_LONG
rather than #ifdef'ing on CONFIG_64BIT, and add a definition for the
offset to the PFN field for use by a later patch.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11217/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The code in build_update_entries for 64 bit physical addresses on a
MIPS64 CPU and 32 bit physical addresses on a MIPS32 CPU is now
identical, with the exception of r4k bug workaround in the latter which
would simply not apply to the former. Remove the duplication and some
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11216/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The cpu_has_rixi cases in build_update_entries are now identical to the
non-RIXI cases with the one exception of the r45k_bvahwbug case which is
hardcoded as never happening anyway & presumably was either missed from
the RIXI path or would never happen on a CPU with RIXI support. Remove
the redundant checks & duplication.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11215/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make use of build_convert_pte_to_entrylo in the RIXI cases within
build_update_entries rather than open-coding it 4 times.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11214/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Prior to release 6 of the MIPS architecture it has been implementation
dependent whether masked interrupts cause a wait instruction to return,
so the kernel has effectively had to maintain a whitelist of cores upon
which it is safe to use the r4k_wait_irqoff cpu_wait implementation.
With MIPSr6 this is no longer implementation dependent and
r4k_wait_irqoff can always be used.

Remove the existing I6400 case which will no longer ever be hit, and was
incorrect anyway since I6400 & r6 in general doesn't have the WII bit.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11210/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Ensure the update to which core the core-other GCR regions reflect has
taken place before any core-other GCRs are accessed by placing a memory
barrier (sync instruction) between the write to the core-other registers
and any such GCR accesses.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11209/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Document that CPC core-other accesses must take place within the bounds
of the CM lock, and begin using the CM lock functions where we access
the GCRs of other cores. This is required because with CM3 the CPC began
using GCR_CL_OTHER instead of CPC_CL_OTHER.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-kernel@vger.kernel.org
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11208/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Introduce mips_cm_lock_other & mips_cm_unlock_other, mirroring the
existing CPC equivalents, in order to lock access from the current core
to another via the core-other GCR region. This hasn't been required in
the past but with CM3 the CPC starts using GCR_CL_OTHER rather than
CPC_CL_OTHER and this will be required for safety.

[ralf@linux-mips.org: Fix merge conflict.]
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11207/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The PVPE (or PVP in >= CM3) field is 10 bits wide, but the mask
previously only covered the bottom 9 bits. Extend the mask to cover all
10 bits of the field.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11206/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

When debugging core bringup it is useful to see the state of the CPC
sequencer, so output that value if the core hasn't started within a
reasonable amount of time (1 second). This avoids simply appearing to
the user to hang if a secondary core fails to start.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: linux-kernel@vger.kernel.org
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11205/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The Config1 register is architecturally defined as required, and is thus
present in all systems which may make use of cps-vec.S. Skip the check
for its presence via the Config.M bit.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11204/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Rather than patching the start of mips_cps_core_entry to provide the
base address of the CM GCRs, simply read that base address from the cop0
CMGCRBase register, converting from the physical address to an uncached
virtual address.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: linux-kernel@vger.kernel.org
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11203/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Provide support for outputting early debug information, in the form of
various register values should an exception occur, during the early
bringup of secondary cores. This code requires an ns16550-compatible
UART accessible from the secondary core, and is written in assembly due
to the environment in which such early exceptions occur where way may
not have a stack, be coherent or even have initialised caches.

[ralf@linux-mips.org: Fix merge conflict.]
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/11202/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Remove the definition in locore.S and move a few of the other similar
definitions in asm/mipsregs.h too. CP0_INTCTL, CP0_SRSCTL, & CP0_SRSMAP
are unused so they're just dropped instead. CP0_DDATA_LO is left where
it is as I have patches to eliminate its use in locore.S and it
otherwise is unlikely to need to be used from assembly code.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11461/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

If the kernel may make use of 64 bit addresses outside of the
compatibility address space then we need to set KX such that those
accesses can succeed. Do so for MIPS64 kernels.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11201/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>