When relocatable support for MIPS was merged, there was no support for
an architecture to add a postlink step for vmlinux. This meant that only
invoking a target within the boot directory, such as uImage, caused the
relocations to be inserted into vmlinux. Building just the vmlinux
target would result in a relocatable kernel with no relocation
information present.
Commit fbe6e37dab ("kbuild: add arch specific post-link Makefile")
recified this situation, so MIPS can now define a postlink step to add
relocation information into vmlinux, and remove the additional steps
tacked onto boot targets.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Tested-by: Steven J. Hill <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14554/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
get_frame_info() calculates the offset of the return address within a
stack frame simply by dividing a the bottom 16 bits of the instruction,
treated as a signed integer, by the size of a long. Whilst this works
for MIPS32 & MIPS64 ISAs where the sw or sd instructions are used, it's
incorrect for microMIPS where encodings differ. The result is that we
typically completely fail to unwind the stack on microMIPS.
Fix this by adjusting is_ra_save_ins() to calculate the return address
offset, and take into account the various different encodings there in
the same place as we consider whether an instruction is storing the
ra/$31 register.
With this we are now able to unwind the stack for kernels targetting the
microMIPS ISA, for example we can produce:
Call Trace:
[<80109e1f>] show_stack+0x63/0x7c
[<8011ea17>] __warn+0x9b/0xac
[<8011ea45>] warn_slowpath_fmt+0x1d/0x20
[<8013fe53>] register_console+0x43/0x314
[<8067c58d>] of_setup_earlycon+0x1dd/0x1ec
[<8067f63f>] early_init_dt_scan_chosen_stdout+0xe7/0xf8
[<8066c115>] do_early_param+0x75/0xac
[<801302f9>] parse_args+0x1dd/0x308
[<8066c459>] parse_early_options+0x25/0x28
[<8066c48b>] parse_early_param+0x2f/0x38
[<8066e8cf>] setup_arch+0x113/0x488
[<8066c4f3>] start_kernel+0x57/0x328
---[ end trace 0000000000000000 ]---
Whereas previously we only produced:
Call Trace:
[<80109e1f>] show_stack+0x63/0x7c
---[ end trace 0000000000000000 ]---
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # v3.10+
Patchwork: https://patchwork.linux-mips.org/patch/14532/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
get_frame_info() is meant to iterate over up to the first 128
instructions within a function, but for microMIPS kernels it will not
reach that many instructions unless the function is 512 bytes long since
we calculate the maximum number of instructions to check by dividing the
function length by the 4 byte size of a union mips_instruction. In
microMIPS kernels this won't do since instructions are variable length.
Fix this by instead checking whether the pointer to the current
instruction has reached the end of the function, and use max_insns as a
simple constant to check the number of iterations against.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # v3.10+
Patchwork: https://patchwork.linux-mips.org/patch/14530/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
During stack unwinding we call a number of functions to determine what
type of instruction we're looking at. The union mips_instruction pointer
provided to them may be pointing at a 2 byte, but not 4 byte, aligned
address & we thus cannot directly access the 4 byte wide members of the
union mips_instruction. To avoid this is_ra_save_ins() copies the
required half-words of the microMIPS instruction to a correctly aligned
union mips_instruction on the stack, which it can then access safely.
The is_jump_ins() & is_sp_move_ins() functions do not correctly perform
this temporary copy, and instead attempt to directly dereference 4 byte
fields which may be misaligned and lead to an address exception.
Fix this by copying the instruction halfwords to a temporary union
mips_instruction in get_frame_info() such that we can provide a 4 byte
aligned union mips_instruction to the is_*_ins() functions and they do
not need to deal with misalignment themselves.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # v3.10+
Patchwork: https://patchwork.linux-mips.org/patch/14529/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
get_frame_info() can be called in microMIPS kernels with the ISA bit
already clear. For example this happens when unwind_stack_by_address()
is called because we begin with a PC that has the ISA bit set & subtract
the (odd) offset from the preceding symbol (which does not have the ISA
bit set). Since get_frame_info() unconditionally subtracts 1 from the PC
in microMIPS kernels it incorrectly misaligns the address it then
attempts to access code at, leading to an address error exception.
Fix this by using msk_isa16_mode() to clear the ISA bit, which allows
get_frame_info() to function regardless of whether it is provided with a
PC that has the ISA bit set or not.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # v3.10+
Patchwork: https://patchwork.linux-mips.org/patch/14528/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When clearing the .bss section in kernel_entry we do so using LONG_S
instructions, and branch whilst the current write address doesn't equal
the end of the .bss section minus the size of a long integer. The .bss
section always begins at a long-aligned address and we always increment
the write pointer by the size of a long integer - we therefore rely upon
the .bss section ending at a long-aligned address. If this is not the
case then the long-aligned write address can never be equal to the
non-long-aligned end address & we will continue to increment past the
end of the .bss section, attempting to zero the rest of memory.
Despite this requirement that .bss end at a long-aligned address we pass
0 as the end alignment requirement to the BSS_SECTION macro and thus
don't guarantee any particular alignment, allowing us to hit the error
condition described above.
Fix this by instead passing 8 bytes as the end alignment argument to
the BSS_SECTION macro, ensuring that the end of the .bss section is
always at least long-aligned.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14526/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This hook provides the platform the chance to perform any required
setup before the boot processor switches to the relocated kernel.
The relocated kernel has been copied and fixed up ready for execution
at this point. Secondary CPUs may wish to switch to it early. There
is also the opportunity for the platform to abort jumping to the
relocated kernel if there is anything wrong with the chosen offset.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: Steven J. Hill <Steven.Hill@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14651/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch enables KASLR for Octeon systems. The SMP startup code is
such that the secondaries monitor the volatile variable
'octeon_processor_relocated_kernel_entry' for any non-zero value.
The 'plat_post_relocation hook' is used to set that value to the
kernel entry point of the relocated kernel. The secondary CPUs will
then jusmp to the new kernel, perform their initialization again
and begin waiting for the boot CPU to start them via the relocated
loop 'octeon_spin_wait_boot'. Inspired by Steven's code from Cavium.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14669/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add in the function needed for Octeon platforms to support KASLR.
Signed-off-by: Steven J. Hill <Steven.Hill@cavium.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When enterring interrupt context via handle_int or except_vec_vi, switch
to the irq_stack of the current CPU if it is not already in use.
The current stack pointer is masked with the thread size and compared to
the base or the irq stack. If it does not match then the stack pointer
is set to the top of that stack, otherwise this is a nested irq being
handled on the irq stack so the stack pointer should be left as it was.
The in-use stack pointer is placed in the callee saved register s1. It
will be saved to the stack when plat_irq_dispatch is invoked and can be
restored once control returns here.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14743/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The SAVE_SOME macro is used to save the execution context on all
exceptions.
If an exception occurs while executing user code, the stack is switched
to the kernel's stack for the current task, and register $28 is switched
to point to the current_thread_info, which is at the bottom of the stack
region.
If the exception occurs while executing kernel code, the stack is left,
and this change ensures that register $28 is not updated. This is the
correct behaviour when the kernel can be executing on the separate irq
stack, because the thread_info will not be at the base of it.
With this change, register $28 is only switched to it's kernel
conventional usage of the currrent thread info pointer at the point at
which execution enters kernel space. Doing it on every exception was
redundant, but OK without an IRQ stack, but will be erroneous once that
is introduced.
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14742/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix the following build error with binutils 2.25.
CC arch/mips/mm/sc-ip22.o
{standard input}: Assembler messages:
{standard input}:132: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:159: Error: number (0x9000000080000000) larger than 32 bits
{standard input}:200: Error: number (0x9000000080000000) larger than 32 bits
scripts/Makefile.build:293: recipe for target 'arch/mips/mm/sc-ip22.o' failed
make[1]: *** [arch/mips/mm/sc-ip22.o] Error 1
MIPS has used .set mips3 to temporarily switch the assembler to 64 bit
mode in 64 bit kernels virtually forever. Binutils 2.25 broke this
behavious partially by happily accepting 64 bit instructions in .set mips3
mode but puking on 64 bit constants when generating 32 bit ELF. Binutils
2.26 restored the old behaviour again.
Fix build with binutils 2.25 by open coding the offending
dli $1, 0x9000000080000000
as
li $1, 0x9000
dsll $1, $1, 48
which is ugly be the only thing that will build on all binutils vintages.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: stable@vger.kernel.org
Use DEVICE_ATTR_WO for write only attributes. This simplifies the
source code, improves readbility, and reduces the chance of
inconsistencies.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@wo@
declarer name DEVICE_ATTR;
identifier x,x_store;
@@
DEVICE_ATTR(x, \(0200\|S_IWUSR\), NULL, x_store);
@script:ocaml@
x << wo.x;
x_store << wo.x_store;
@@
if not (x^"_store" = x_store) then Coccilib.include_match false
@@
declarer name DEVICE_ATTR_WO;
identifier wo.x,wo.x_store;
@@
- DEVICE_ATTR(x, \(0200\|S_IWUSR\), NULL, x_store);
+ DEVICE_ATTR_WO(x);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14463/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The license text has been mangled at some point then copy pasted across
multiple files. Restore it to what it should be.
Note that this is not intended as a license change.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
After
1. commit 9f5ce39ddb ("ARM: shmobile: rcar-gen2: Obtain extal
frequency from DT"),
2. commit 80951f04c3 ("ARM: shmobile: rcar-gen2: Stop passing
mode pins state to clock driver"),
3. and handling of debug resource reset,
there are no more users of rcar_gen2_read_mode_pins() left.
Remove the function and its support definitions.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Now debug resource reset is handled properly, allow booting secondary
CPU cores when hardware debug mode is enabled (MD21=1, SW8-4=OFF on
koelsch) on legacy r8a7791.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Now debug resource reset is handled properly, allow booting secondary
CPU cores when hardware debug mode is enabled (MD21=1) on SoCs using the
"renesas,apmu" enable method.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
In debug mode (MD21=1), reset requests derived from power-shutoff to the
AP-system CPU cores must be enabled before the AP-system CPU cores
resume from power-shutoff for the first time. Else resume may fail,
causing the system to hang during boot.
As setting these bits is a no-op in normal mode, there's no need to
check the actual state of MD21 first.
Inspired by CPU-specific patches in the BSP by Hisashi Nakamura
<hisashi.nakamura.ak@renesas.com>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Use recently added R-Car Gen 2 fallback binding for msiof nodes in
DT for r8a7790 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7790 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for msiof nodes in
DT for r8a7792 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7792 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for msiof nodes in
DT for r8a7791 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7791 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for iic nodes in
DT for r8a7794 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7794 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for iic nodes in
DT for r8a7793 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7793 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for iic nodes in
DT for r8a7791 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7791 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Use recently added R-Car Gen 2 fallback binding for iic nodes in
DT for r8a7790 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7790 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for i2c nodes in
DT for r8a7794 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7794 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for i2c nodes in
DT for r8a7793 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7793 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for i2c nodes in
DT for r8a7792 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7792 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for i2c nodes in
DT for r8a7791 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7791 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 2 fallback binding for i2c nodes in
DT for r8a7790 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7790 and the
fallback binding for R-Car Gen 2.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 1 fallback binding for i2c nodes in
DT for r8a7778 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7778 and the
fallback binding for R-Car Gen 1.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Use recently added R-Car Gen 1 fallback binding for i2c nodes in
DT for r8a7779 SoC.
This has no run-time effect for the current driver as the initialisation
sequence is the same for the SoC-specific binding for r8a7779 and the
fallback binding for R-Car Gen 1.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
