linux-stable.git/arch/xtensa, branch v5.4.166

xtensa: xtfpga: Try software restart before simulating CPU reset

2021-10-27T07:54:25+00:00

[ Upstream commit 012e974501a270d8dfd4ee2039e1fdf7579c907e ]

Rebooting xtensa images loaded with the '-kernel' option in qemu does
not work. When executing a reboot command, the qemu session either hangs
or experiences an endless sequence of error messages.

  Kernel panic - not syncing: Unrecoverable error in exception handler

Reset code jumps to the CPU restart address, but Linux can not recover
from there because code and data in the kernel init sections have been
discarded and overwritten at this point.

XTFPGA platforms have a means to reset the CPU by writing 0xdead into a
specific FPGA IO address. When used in QEMU the kernel image loaded with
the '-kernel' option gets restored to its original state allowing the
machine to boot successfully.

Use that mechanism to attempt a platform reset. If it does not work,
fall back to the existing mechanism.

Signed-off-by: Guenter Roeck 
Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: xtfpga: use CONFIG_USE_OF instead of CONFIG_OF

2021-10-27T07:54:25+00:00

[ Upstream commit f3d7c2cdf6dc0d5402ec29c3673893b3542c5ad1 ]

Use platform data to initialize xtfpga device drivers when CONFIG_USE_OF
is not selected. This fixes xtfpga networking when CONFIG_USE_OF is not
selected but CONFIG_OF is.

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: call irqchip_init only when CONFIG_USE_OF is selected

2021-10-13T08:08:18+00:00

[ Upstream commit 6489f8d0e1d93a3603d8dad8125797559e4cf2a2 ]

During boot time kernel configured with OF=y but USE_OF=n displays the
following warnings and hangs shortly after starting userspace:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at kernel/irq/irqdomain.c:695 irq_create_mapping_affinity+0x29/0xc0
irq_create_mapping_affinity(, 6) called with NULL domain
CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.0-rc3-00001-gd67ed2510d28 #30
Call Trace:
  __warn+0x69/0xc4
  warn_slowpath_fmt+0x6c/0x94
  irq_create_mapping_affinity+0x29/0xc0
  local_timer_setup+0x40/0x88
  time_init+0xb1/0xe8
  start_kernel+0x31d/0x3f4
  _startup+0x13b/0x13b
---[ end trace 1e6630e1c5eda35b ]---
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at arch/xtensa/kernel/time.c:141 local_timer_setup+0x58/0x88
error: can't map timer irq
CPU: 0 PID: 0 Comm: swapper Tainted: G        W         5.15.0-rc3-00001-gd67ed2510d28 #30
Call Trace:
  __warn+0x69/0xc4
  warn_slowpath_fmt+0x6c/0x94
  local_timer_setup+0x58/0x88
  time_init+0xb1/0xe8
  start_kernel+0x31d/0x3f4
  _startup+0x13b/0x13b
---[ end trace 1e6630e1c5eda35c ]---
Failed to request irq 0 (timer)

Fix that by calling irqchip_init only when CONFIG_USE_OF is selected and
calling legacy interrupt controller init otherwise.

Fixes: da844a81779e ("xtensa: add device trees support")
Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: use CONFIG_USE_OF instead of CONFIG_OF

2021-10-13T08:08:18+00:00

[ Upstream commit d67ed2510d28a1eb33171010d35cf52178cfcbdd ]

CONFIG_OF can be set by a randconfig or by a user -- without setting the
early flattree option (OF_EARLY_FLATTREE).  This causes build errors.
However, if randconfig or a user sets USE_OF in the Xtensa config,
the right kconfig symbols are set to fix the build.

Fixes these build errors:

../arch/xtensa/kernel/setup.c:67:19: error: ‘__dtb_start’ undeclared here (not in a function); did you mean ‘dtb_start’?
   67 | void *dtb_start = __dtb_start;
      |                   ^~~~~~~~~~~
../arch/xtensa/kernel/setup.c: In function 'xtensa_dt_io_area':
../arch/xtensa/kernel/setup.c:201:14: error: implicit declaration of function 'of_flat_dt_is_compatible'; did you mean 'of_machine_is_compatible'? [-Werror=implicit-function-declaration]
  201 |         if (!of_flat_dt_is_compatible(node, "simple-bus"))
../arch/xtensa/kernel/setup.c:204:18: error: implicit declaration of function 'of_get_flat_dt_prop' [-Werror=implicit-function-declaration]
  204 |         ranges = of_get_flat_dt_prop(node, "ranges", &len);
../arch/xtensa/kernel/setup.c:204:16: error: assignment to 'const __be32 *' {aka 'const unsigned int *'} from 'int' makes pointer from integer without a cast [-Werror=int-conversion]
  204 |         ranges = of_get_flat_dt_prop(node, "ranges", &len);
      |                ^
../arch/xtensa/kernel/setup.c: In function 'early_init_devtree':
../arch/xtensa/kernel/setup.c:228:9: error: implicit declaration of function 'early_init_dt_scan'; did you mean 'early_init_devtree'? [-Werror=implicit-function-declaration]
  228 |         early_init_dt_scan(params);
../arch/xtensa/kernel/setup.c:229:9: error: implicit declaration of function 'of_scan_flat_dt' [-Werror=implicit-function-declaration]
  229 |         of_scan_flat_dt(xtensa_dt_io_area, NULL);

xtensa-elf-ld: arch/xtensa/mm/mmu.o:(.text+0x0): undefined reference to `xtensa_kio_paddr'

Fixes: da844a81779e ("xtensa: add device trees support")
Fixes: 6cb971114f63 ("xtensa: remap io area defined in device tree")
Signed-off-by: Randy Dunlap 
Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: move XCHAL_KIO_* definitions to kmem_layout.h

2021-10-13T08:08:18+00:00

[ Upstream commit 6591685d50043f615a1ad7ddd5bb263ef54808fc ]

These address and size definitions define xtensa kernel memory layout,
move them from vectors.h to the kmem_layout.h

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: ISS: don't panic in rs_init

2021-09-22T10:26:30+00:00

[ Upstream commit 23411c720052ad860b3e579ee4873511e367130a ]

While alloc_tty_driver failure in rs_init would mean we have much bigger
problem, there is no reason to panic when tty_register_driver fails
there. It can fail for various reasons.

So handle the failure gracefully. Actually handle them both while at it.
This will make at least the console functional as it was enabled earlier
by console_initcall in iss_console_init. Instead of shooting down the
whole system.

We move tty_port_init() after alloc_tty_driver(), so that we don't need
to destroy the port in case the latter function fails.

Cc: Chris Zankel 
Cc: Max Filippov 
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Max Filippov 
Signed-off-by: Jiri Slaby 
Link: https://lore.kernel.org/r/20210723074317.32690-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

xtensa: fix kconfig unmet dependency warning for HAVE_FUTEX_CMPXCHG

2021-09-12T06:56:39+00:00

commit ed5aacc81cd41efc4d561e14af408d1003f7b855 upstream.

XTENSA should only select HAVE_FUTEX_CMPXCHG when FUTEX is
set/enabled. This prevents a kconfig warning.

WARNING: unmet direct dependencies detected for HAVE_FUTEX_CMPXCHG
  Depends on [n]: FUTEX [=n]
  Selected by [y]:
  - XTENSA [=y] && !MMU [=n]

Fixes: d951ba21b959 ("xtensa: nommu: select HAVE_FUTEX_CMPXCHG")
Signed-off-by: Randy Dunlap 
Cc: Max Filippov 
Cc: Chris Zankel 
Cc: linux-xtensa@linux-xtensa.org
Message-Id: <20210526070337.28130-1-rdunlap@infradead.org>
Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: move coprocessor_flush to the .text section

2021-04-07T12:47:42+00:00

commit ab5eb336411f18fd449a1fb37d36a55ec422603f upstream.

coprocessor_flush is not a part of fast exception handlers, but it uses
parts of fast coprocessor handling code that's why it's in the same
source file. It uses call0 opcode to invoke those parts so there are no
limitations on their relative location, but the rest of the code calls
coprocessor_flush with call8 and that doesn't work when vectors are
placed in a different gigabyte-aligned area than the rest of the kernel.

Move coprocessor_flush from the .exception.text section to the .text so
that it's reachable from the rest of the kernel with call8.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: uaccess: Add missing __user to strncpy_from_user() prototype

2020-12-02T07:49:49+00:00

[ Upstream commit dc293f2106903ab9c24e9cea18c276e32c394c33 ]

When adding __user annotations in commit 2adf5352a34a, the
strncpy_from_user() function declaration for the
CONFIG_GENERIC_STRNCPY_FROM_USER case was missed. Fix it.

Reported-by: kernel test robot 
Signed-off-by: Laurent Pinchart 
Message-Id: <20200831210937.17938-1-laurent.pinchart@ideasonboard.com>
Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: disable preemption around cache alias management calls

2020-11-24T12:29:23+00:00

commit 3a860d165eb5f4d7cf0bf81ef6a5b5c5e1754422 upstream.

Although cache alias management calls set up and tear down TLB entries
and fast_second_level_miss is able to restore TLB entry should it be
evicted they absolutely cannot preempt each other because they use the
same TLBTEMP area for different purposes.
Disable preemption around all cache alias management calls to enforce
that.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman