linux-stable.git/arch/arm, branch linux-4.9.y

ARM: 9256/1: NWFPE: avoid compiler-generated __aeabi_uldivmod

2023-01-07T11:07:36+00:00

commit 3220022038b9a3845eea762af85f1c5694b9f861 upstream.

clang-15's ability to elide loops completely became more aggressive when
it can deduce how a variable is being updated in a loop. Counting down
one variable by an increment of another can be replaced by a modulo
operation.

For 64b variables on 32b ARM EABI targets, this can result in the
compiler generating calls to __aeabi_uldivmod, which it does for a do
while loop in float64_rem().

For the kernel, we'd generally prefer that developers not open code 64b
division via binary / operators and instead use the more explicit
helpers from div64.h. On arm-linux-gnuabi targets, failure to do so can
result in linkage failures due to undefined references to
__aeabi_uldivmod().

While developers can avoid open coding divisions on 64b variables, the
compiler doesn't know that the Linux kernel has a partial implementation
of a compiler runtime (--rtlib) to enforce this convention.

It's also undecidable for the compiler whether the code in question
would be faster to execute the loop vs elide it and do the 64b division.

While I actively avoid using the internal -mllvm command line flags, I
think we get better code than using barrier() here, which will force
reloads+spills in the loop for all toolchains.

Link: https://github.com/ClangBuiltLinux/linux/issues/1666

Reported-by: Nathan Chancellor 
Reviewed-by: Arnd Bergmann 
Signed-off-by: Nick Desaulniers 
Tested-by: Nathan Chancellor 
Cc: stable@vger.kernel.org
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Greg Kroah-Hartman

ARM: mmp: fix timer_read delay

2023-01-07T11:07:13+00:00

[ Upstream commit e348b4014c31041e13ff370669ba3348c4d385e3 ]

timer_read() was using an empty 100-iteration loop to wait for the
TMR_CVWR register to capture the latest timer counter value. The delay
wasn't long enough. This resulted in CPU idle time being extremely
underreported on PXA168 with CONFIG_NO_HZ_IDLE=y.

Switch to the approach used in the vendor kernel, which implements the
capture delay by reading TMR_CVWR a few times instead.

Fixes: 49cbe78637eb ("[ARM] pxa: add base support for Marvell's PXA168 processor line")
Signed-off-by: Doug Brown 
Link: https://lore.kernel.org/r/20221204005117.53452-3-doug@schmorgal.com
Signed-off-by: Arnd Bergmann 
Signed-off-by: Sasha Levin

ARM: dts: armada-39x: Fix assigned-addresses for every PCIe Root Port

2023-01-07T11:07:12+00:00

[ Upstream commit 69236d2391b4d7324b11c3252921571577892e7b ]

BDF of resource in DT assigned-addresses property of Marvell PCIe Root Port
(PCI-to-PCI bridge) should match BDF in address part in that DT node name
as specified resource belongs to Marvell PCIe Root Port itself.

Fixes: 538da83ddbea ("ARM: mvebu: add Device Tree files for Armada 39x SoC and board")
Signed-off-by: Pali Rohár 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Sasha Levin

ARM: dts: armada-38x: Fix assigned-addresses for every PCIe Root Port

2023-01-07T11:07:12+00:00

[ Upstream commit 44f47b7a8fa4678ce4c38ea74837e4996b9df6d6 ]

BDF of resource in DT assigned-addresses property of Marvell PCIe Root Port
(PCI-to-PCI bridge) should match BDF in address part in that DT node name
as specified resource belongs to Marvell PCIe Root Port itself.

Fixes: 0d3d96ab0059 ("ARM: mvebu: add Device Tree description of the Armada 380/385 SoCs")
Signed-off-by: Pali Rohár 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Sasha Levin

ARM: dts: armada-375: Fix assigned-addresses for every PCIe Root Port

2023-01-07T11:07:12+00:00

[ Upstream commit 823956d2436f70ced74c0fe8ab99facd8abfc060 ]

BDF of resource in DT assigned-addresses property of Marvell PCIe Root Port
(PCI-to-PCI bridge) should match BDF in address part in that DT node name
as specified resource belongs to Marvell PCIe Root Port itself.

Fixes: 4de59085091f ("ARM: mvebu: add Device Tree description of the Armada 375 SoC")
Signed-off-by: Pali Rohár 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Sasha Levin

ARM: dts: armada-xp: Fix assigned-addresses for every PCIe Root Port

2023-01-07T11:07:12+00:00

[ Upstream commit eab276787f456cbea89fabea110fe0728673d308 ]

BDF of resource in DT assigned-addresses property of Marvell PCIe Root Port
(PCI-to-PCI bridge) should match BDF in address part in that DT node name
as specified resource belongs to Marvell PCIe Root Port itself.

Fixes: 9d8f44f02d4a ("arm: mvebu: add PCIe Device Tree informations for Armada XP")
Fixes: 12b69a599745 ("ARM: mvebu: second PCIe unit of Armada XP mv78230 is only x1 capable")
Fixes: 2163e61c92d9 ("ARM: mvebu: fix second and third PCIe unit of Armada XP mv78260")
Signed-off-by: Pali Rohár 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Sasha Levin

ARM: dts: armada-370: Fix assigned-addresses for every PCIe Root Port

2023-01-07T11:07:12+00:00

[ Upstream commit d9208b0fa2e803d16b28d91bf1d46b7ee9ea13c6 ]

BDF of resource in DT assigned-addresses property of Marvell PCIe Root Port
(PCI-to-PCI bridge) should match BDF in address part in that DT node name
as specified resource belongs to Marvell PCIe Root Port itself.

Fixes: a09a0b7c6ff1 ("arm: mvebu: add PCIe Device Tree informations for Armada 370")
Signed-off-by: Pali Rohár 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Sasha Levin

ARM: dts: dove: Fix assigned-addresses for every PCIe Root Port

2023-01-07T11:07:12+00:00

[ Upstream commit dcc7d8c72b64a479b8017e4332d99179deb8802d ]

BDF of resource in DT assigned-addresses property of Marvell PCIe Root Port
(PCI-to-PCI bridge) should match BDF in address part in that DT node name
as specified resource belongs to Marvell PCIe Root Port itself.

Fixes: 74ecaa403a74 ("ARM: dove: add PCIe controllers to SoC DT")
Signed-off-by: Pali Rohár 
Signed-off-by: Gregory CLEMENT 
Signed-off-by: Sasha Levin

arm: dts: spear600: Fix clcd interrupt

2023-01-07T11:07:12+00:00

[ Upstream commit 0336e2ce34e7a89832b6c214f924eb7bc58940be ]

Interrupt 12 of the Interrupt controller belongs to the SMI controller,
the right one for the display controller is the interrupt 13.

Fixes: 8113ba917dfa ("ARM: SPEAr: DT: Update device nodes")
Signed-off-by: Kory Maincent 
Acked-by: Viresh Kumar 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Sasha Levin

ARM: 9251/1: perf: Fix stacktraces for tracepoint events in THUMB2 kernels

2022-12-14T10:24:32+00:00

[ Upstream commit 612695bccfdbd52004551308a55bae410e7cd22f ]

Store the frame address where arm_get_current_stackframe() looks for it
(ARM_r7 instead of ARM_fp if CONFIG_THUMB2_KERNEL=y). Otherwise frame->fp
gets set to 0, causing unwind_frame() to fail.

  # bpftrace -e 't:sched:sched_switch { @[kstack] = count(); exit(); }'
  Attaching 1 probe...
  @[
      __schedule+1059
  ]: 1

A typical first unwind instruction is 0x97 (SP = R7), so after executing
it SP ends up being 0 and -URC_FAILURE is returned.

  unwind_frame(pc = ac9da7d7 lr = 00000000 sp = c69bdda0 fp = 00000000)
  unwind_find_idx(ac9da7d7)
  unwind_exec_insn: insn = 00000097
  unwind_exec_insn: fp = 00000000 sp = 00000000 lr = 00000000 pc = 00000000

With this patch:

  # bpftrace -e 't:sched:sched_switch { @[kstack] = count(); exit(); }'
  Attaching 1 probe...
  @[
      __schedule+1059
      __schedule+1059
      schedule+79
      schedule_hrtimeout_range_clock+163
      schedule_hrtimeout_range+17
      ep_poll+471
      SyS_epoll_wait+111
      sys_epoll_pwait+231
      __ret_fast_syscall+1
  ]: 1

Link: https://lore.kernel.org/r/20220920230728.2617421-1-tnovak@fb.com/

Reviewed-by: Linus Walleij 
Signed-off-by: Tomislav Novak 
Signed-off-by: Russell King (Oracle) 
Signed-off-by: Sasha Levin