Linux kernel ============ The Linux kernel is the core of any Linux operating system. It manages hardware, system resources, and provides the fundamental services for all other software. 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Prabhakar <prabhakar.csengg@gmail.com> says:
This patch series addresses three issues in the RZV2H RSPI driver:
1. The max_speed_hz field was advertising a prohibited bit rate, which
could lead to incorrect behavior when userspace applications attempt
to set the SPI clock speed.
2. The clock configuration logic allowed for an invalid combination of
SPR=0 and BRDV=0, which is not supported by the hardware.
3. Simplified the clock rate search function as min/max speed parameters
are not needed.
Note, patches apply on top of next-20260409.
Make sure to deregister the controller before releasing underlying
resources like DMA during driver unbind.
Fixes: 4178b6b1b595 ("spi: fsl-(e)spi: migrate to using devm_ functions to simplify cleanup")
Cc: stable@vger.kernel.org # 4.3
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260410064749.496888-1-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The spr_min and spr_max parameters passed to
rzv2h_rspi_find_rate_variable() and rzv2h_rspi_find_rate_fixed() were
always called with RSPI_SPBR_SPR_MIN and RSPI_SPBR_SPR_MAX respectively.
There is no need to pass these as parameters since the valid SPR range
is fixed by the hardware.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://patch.msgid.link/20260410080517.2405700-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Needed for Johan's controller deregistration ordering changes.
The combination of SPR=0 and BRDV=0 results in the minimum division
ratio of 2, producing the maximum possible bit rate for a given clock
source. This combination is not supported in two cases:
- On RZ/G3E, RZ/G3L, RZ/V2H(P) and RZ/V2N, RSPI_n_TCLK is fixed at
200MHz, which would yield 100Mbps. The next hardware manual update
will explicitly state that since the maximum frequency of the
RSPICKn clock signal is 50MHz, settings with N=0 and n=0 resulting
in 100Mbps are prohibited.
- On RZ/T2H and RZ/N2H, when PCLK (125MHz) is used as the clock
source, SPR=0 and BRDV=0 is explicitly listed as unsupported in
the hardware manual (Table 36.7).
Skip the SPR=0/BRDV=0 combination in rzv2h_rspi_find_rate_fixed() to
prevent the driver from selecting an invalid clock configuration on the
affected SoCs.
Additionally, remove the now redundant RSPI_SPBR_SPR_PCLK_MIN define
which was previously set to 1 to work around the PCLK restriction, but
was overly broad as it incorrectly blocked valid combinations such as
SPR=0/BRDV=1 (31.25Mbps on PCLK=125MHz).
Fixes: 8b61c8919dff ("spi: Add driver for the RZ/V2H(P) RSPI IP")
Fixes: 1ce3e8adc7d0 ("spi: rzv2h-rspi: add support for using PCLK for transfer clock")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://patch.msgid.link/20260410080517.2405700-3-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Make sure to deregister the controller before disabling underlying
resources like interrupts during driver unbind.
Fixes: 9ac8d17694b6 ("spi: add support for microchip fpga spi controllers")
Cc: stable@vger.kernel.org # 6.0
Cc: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260409120419.388546-21-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Due to additional responsibilities, Raju Rangoju will no longer be
supporting AMD SPI driver. Maintenance will be handled by Krishnamoorthi
going forward.
Cc: Krishnamoorthi M <krishnamoorthi.m@amd.com>
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Link: https://patch.msgid.link/20260406091042.4065767-1-Raju.Rangoju@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>
On RZ/V2H(P), RZ/G3E and RZ/G3L, RSPI_n_TCLK is fixed at 200MHz.
The max_speed_hz was computed using clk_round_rate(tclk, ULONG_MAX)
with SPR=0 and BRDV=0, resulting in 100Mbps - the exact combination
prohibited on these SoCs. This could cause the SPI framework to request
a speed that rzv2h_rspi_find_rate_fixed() would skip, potentially
leading to a clock selection failure.
On RZ/T2H and RZ/N2H the max_speed_hz was correctly calculated as
50Mbps for both the variable PCLKSPIn and fixed PCLK clock sources.
Since the maximum supported bit rate is 50Mbps across all supported SoC
variants, replace the clk_round_rate() based calculation with a define
RSPI_MAX_SPEED_HZ set to 50MHz and use it directly for max_speed_hz.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://patch.msgid.link/20260410080517.2405700-2-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Make sure to deregister the controller before disabling underlying
resources like interrupts during driver unbind.
Fixes: 059f545832be ("spi: add support for microchip "soft" spi controller")
Cc: stable@vger.kernel.org # 6.19
Cc: Prajna Rajendra Kumar <prajna.rajendrakumar@microchip.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260409120419.388546-20-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Replace devm_clk_get() followed by clk_prepare_enable() with
devm_clk_get_enabled() for both "pclk" and "ref_clk". This removes
the need for explicit clock enable and disable calls, as the managed
API automatically disables the clocks on device removal or probe
failure.
Remove the now-unnecessary clk_disable_unprepare() calls from the
probe error paths and the remove callback. Simplify error handling
by jumping directly to the remove_ctlr label.
Signed-off-by: Pei Xiao <xiaopei01@kylinos.cn>
Acked-by: Michal Simek <michal.simek@amd.com>
Link: https://patch.msgid.link/24043625f89376da36feca2408f990a85be7ab36.1775555500.git.xiaopei01@kylinos.cn
Signed-off-by: Mark Brown <broonie@kernel.org>
Make sure to deregister the controller before disabling underlying
resources like interrupts during driver unbind.
Fixes: 8596124c4c1b ("spi: microchip-core-qspi: Add support for microchip fpga qspi controllers")
Cc: stable@vger.kernel.org # 6.1
Cc: Naga Sureshkumar Relli <nagasuresh.relli@microchip.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260409120419.388546-19-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull RISC-V fixes from Paul Walmsley:
- Fix a CONFIG_SPARSEMEM crash on RV32 by avoiding early phys_to_page()
- Prevent runtime const infrastructure from being used by modules,
similar to what was done for x86
- Avoid problems when shutting down ACPI systems with IOMMUs by adding
a device dependency between IOMMU and devices that use it
- Fix a bug where the CPU pointer masking state isn't properly reset
when tagged addresses aren't enabled for a task
- Fix some incorrect register assignments, and add some missing ones,
in kgdb support code
- Fix compilation of non-kernel code that uses the ptrace uapi header
by replacing BIT() with _BITUL()
- Fix compilation of the validate_v_ptrace kselftest by working around
kselftest macro expansion issues
* tag 'riscv-for-linus-7.0-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
ACPI: RIMT: Add dependency between iommu and devices
selftests: riscv: Add braces around EXPECT_EQ()
riscv: use _BITUL macro rather than BIT() in ptrace uapi and kselftests
riscv: Reset pmm when PR_TAGGED_ADDR_ENABLE is not set
riscv: make runtime const not usable by modules
riscv: patch: Avoid early phys_to_page()
riscv: kgdb: fix several debug register assignment bugs
Make sure to deregister the controller before disabling it to allow SPI
device drivers to do I/O during deregistration.
Fixes: 454fa271bc4e ("spi: Add Meson SPICC driver")
Cc: stable@vger.kernel.org # 4.13
Cc: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260409120419.388546-18-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Pull x86 fixes from Ingo Molnar:
- Fix kexec crash on KCOV-instrumented kernels (Aleksandr Nogikh)
- Fix Geode platform driver on-stack property data use-after-return
bug (Dmitry Torokhov)
* tag 'x86-urgent-2026-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform/geode: Fix on-stack property data use-after-return bug
x86/kexec: Disable KCOV instrumentation after load_segments()
EPROBE_DEFER ensures IOMMU devices are probed before the devices that
depend on them. During shutdown, however, the IOMMU may be removed
first, leading to issues. To avoid this, a device link is added
which enforces the correct removal order.
Fixes: 8f7729552582 ("ACPI: RISC-V: Add support for RIMT")
Signed-off-by: Sunil V L <sunilvl@oss.qualcomm.com>
Link: https://patch.msgid.link/20260303061605.722949-1-sunilvl@oss.qualcomm.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>