This is a note to let you know that I've just added the patch titled clk: lpc32xx: add a quirk for PWM and MS clock dividers to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: clk-lpc32xx-add-a-quirk-for-pwm-and-ms-clock-dividers.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon Apr 10 17:14:09 CEST 2017 From: alexander.levin@xxxxxxxxxxx Date: Tue, 4 Apr 2017 19:32:03 +0000 Subject: clk: lpc32xx: add a quirk for PWM and MS clock dividers To: "gregkh@xxxxxxxxxxxxxxxxxxx" <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: "stable@xxxxxxxxxxxxxxx" <stable@xxxxxxxxxxxxxxx> Message-ID: <20170404193158.19041-3-alexander.levin@xxxxxxxxxxx> From: Vladimir Zapolskiy <vz@xxxxxxxxx> [ Upstream commit f84d42a9cffc4ecd96f1ce3a038f841782142eb2 ] In common clock framework CLK_DIVIDER_ONE_BASED or'ed with CLK_DIVIDER_ALLOW_ZERO flags indicates that 1) a divider clock may be set to zero value, 2) divider's zero value is interpreted as a non-divided clock. On the LPC32xx platform clock dividers of PWM and memory card clocks comply with the first condition, but zero value means a gated clock, thus it may happen that the divider value is not updated when the clock is enabled and the clock remains gated. The change adds one-shot quirks, which check for zero value of divider on initialization and set it to a non-zero value, therefore in runtime a gate clock will work as expected. Signed-off-by: Vladimir Zapolskiy <vz@xxxxxxxxx> Reviewed-by: Sylvain Lemieux <slemieux.tyco@xxxxxxxxx> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/clk/nxp/clk-lpc32xx.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) --- a/drivers/clk/nxp/clk-lpc32xx.c +++ b/drivers/clk/nxp/clk-lpc32xx.c @@ -1282,13 +1282,13 @@ static struct clk_hw_proto clk_hw_proto[ LPC32XX_DEFINE_MUX(PWM1_MUX, PWMCLK_CTRL, 1, 0x1, NULL, 0), LPC32XX_DEFINE_DIV(PWM1_DIV, PWMCLK_CTRL, 4, 4, NULL, - CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO), + CLK_DIVIDER_ONE_BASED), LPC32XX_DEFINE_GATE(PWM1_GATE, PWMCLK_CTRL, 0, 0), LPC32XX_DEFINE_COMPOSITE(PWM1, PWM1_MUX, PWM1_DIV, PWM1_GATE), LPC32XX_DEFINE_MUX(PWM2_MUX, PWMCLK_CTRL, 3, 0x1, NULL, 0), LPC32XX_DEFINE_DIV(PWM2_DIV, PWMCLK_CTRL, 8, 4, NULL, - CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO), + CLK_DIVIDER_ONE_BASED), LPC32XX_DEFINE_GATE(PWM2_GATE, PWMCLK_CTRL, 2, 0), LPC32XX_DEFINE_COMPOSITE(PWM2, PWM2_MUX, PWM2_DIV, PWM2_GATE), @@ -1335,8 +1335,7 @@ static struct clk_hw_proto clk_hw_proto[ LPC32XX_DEFINE_GATE(USB_DIV_GATE, USB_CTRL, 17, 0), LPC32XX_DEFINE_COMPOSITE(USB_DIV, _NULL, USB_DIV_DIV, USB_DIV_GATE), - LPC32XX_DEFINE_DIV(SD_DIV, MS_CTRL, 0, 4, NULL, - CLK_DIVIDER_ONE_BASED | CLK_DIVIDER_ALLOW_ZERO), + LPC32XX_DEFINE_DIV(SD_DIV, MS_CTRL, 0, 4, NULL, CLK_DIVIDER_ONE_BASED), LPC32XX_DEFINE_CLK(SD_GATE, MS_CTRL, BIT(5) | BIT(9), BIT(5) | BIT(9), 0x0, BIT(5) | BIT(9), 0x0, 0x0, clk_mask_ops), LPC32XX_DEFINE_COMPOSITE(SD, _NULL, SD_DIV, SD_GATE), @@ -1478,6 +1477,20 @@ static struct clk * __init lpc32xx_clk_r return clk; } +static void __init lpc32xx_clk_div_quirk(u32 reg, u32 div_mask, u32 gate) +{ + u32 val; + + regmap_read(clk_regmap, reg, &val); + + if (!(val & div_mask)) { + val &= ~gate; + val |= BIT(__ffs(div_mask)); + } + + regmap_update_bits(clk_regmap, reg, gate | div_mask, val); +} + static void __init lpc32xx_clk_init(struct device_node *np) { unsigned int i; @@ -1517,6 +1530,17 @@ static void __init lpc32xx_clk_init(stru return; } + /* + * Divider part of PWM and MS clocks requires a quirk to avoid + * a misinterpretation of formally valid zero value in register + * bitfield, which indicates another clock gate. Instead of + * adding complexity to a gate clock ensure that zero value in + * divider clock is never met in runtime. + */ + lpc32xx_clk_div_quirk(LPC32XX_CLKPWR_PWMCLK_CTRL, 0xf0, BIT(0)); + lpc32xx_clk_div_quirk(LPC32XX_CLKPWR_PWMCLK_CTRL, 0xf00, BIT(2)); + lpc32xx_clk_div_quirk(LPC32XX_CLKPWR_MS_CTRL, 0xf, BIT(5) | BIT(9)); + for (i = 1; i < LPC32XX_CLK_MAX; i++) { clk[i] = lpc32xx_clk_register(i); if (IS_ERR(clk[i])) { Patches currently in stable-queue which might be from gregkh@xxxxxxxxxxxxxxxxxxx are queue-4.9/staging-android-ashmem-lseek-failed-due-to-no-fmode_lseek.patch queue-4.9/sysfs-be-careful-of-error-returns-from-ops-show.patch queue-4.9/mips-flush-wrong-invalid-ftlb-entry-for-huge-page.patch queue-4.9/mips-end-spinlocks-with-.insn.patch queue-4.9/kvm-arm-arm64-fix-locking-for-kvm_free_stage2_pgd.patch queue-4.9/powerpc-disable-hfscr-if-tm-is-not-supported.patch queue-4.9/metag-usercopy-add-missing-fixups.patch queue-4.9/nios2-reserve-boot-memory-for-device-tree.patch queue-4.9/ring-buffer-fix-return-value-check-in-test_ringbuffer.patch queue-4.9/ppdev-check-before-attaching-port.patch queue-4.9/powerpc-64-fix-flush_-d-i-cache_range-called-from-modules.patch queue-4.9/drm-sun4i-tcon-move-soc-specific-quirks-to-a-dt-matched-data-structure.patch queue-4.9/acpi-gpio-do-not-fall-back-to-parsing-_crs-when-we-get-a-deferral.patch queue-4.9/metag-usercopy-add-early-abort-to-copy_to_user.patch queue-4.9/powerpc-crypto-crc32c-vpmsum-fix-missing-preempt_disable.patch queue-4.9/arm-arm64-kvm-take-mmap_sem-in-kvm_arch_prepare_memory_region.patch queue-4.9/mips-ralink-fix-typos-in-rt3883-pinctrl.patch queue-4.9/cfg80211-check-rdev-resume-callback-only-for-registered-wiphy.patch queue-4.9/metag-usercopy-set-flags-before-addz.patch queue-4.9/metag-usercopy-fix-src-fixup-in-from-user-rapf-loops.patch queue-4.9/drm-sun4i-add-compatible-string-for-a31-a31s-tcon-timing-controller.patch queue-4.9/xtensa-make-__pa-work-with-uncached-kseg-addresses.patch queue-4.9/clk-lpc32xx-add-a-quirk-for-pwm-and-ms-clock-dividers.patch queue-4.9/powerpc-mm-add-missing-global-tlb-invalidate-if-cxl-is-active.patch queue-4.9/brcmfmac-use-local-iftype-avoiding-use-after-free-of-virtual-interface.patch queue-4.9/drm-vmwgfx-remove-getparam-error-message.patch queue-4.9/mac80211-unconditionally-start-new-netdev-queues-with-itxq-support.patch queue-4.9/dm-verity-fec-fix-bufio-leaks.patch queue-4.9/drm-vmwgfx-type-check-lookups-of-fence-objects.patch queue-4.9/drm-sun4i-add-compatible-strings-for-a31-a31s-display-pipelines.patch queue-4.9/dm-verity-fec-limit-error-correction-recursion.patch queue-4.9/s390-uaccess-get_user-should-zero-on-failure-again.patch queue-4.9/dm-raid-fix-null-pointer-dereference-for-raid1-without-bitmap.patch queue-4.9/random-use-chacha20-for-get_random_int-long.patch queue-4.9/ptrace-fix-ptrace_listen-race-corrupting-task-state.patch queue-4.9/drm-vmwgfx-fix-integer-overflow-in-vmw_surface_define_ioctl.patch queue-4.9/hid-i2c-hid-add-a-simple-quirk-to-fix-device-defects.patch queue-4.9/s390-decompressor-fix-initrd-corruption-caused-by-bss-clear.patch queue-4.9/mips-check-tlb-before-handle_ri_rdhwr-for-loongson-3.patch queue-4.9/metag-usercopy-drop-unused-macros.patch queue-4.9/iio-bmg160-reset-chip-when-probing.patch queue-4.9/orangefs-move-features-validation-to-fix-filesystem-hang.patch queue-4.9/arm64-mm-unaligned-access-by-user-land-should-be-received-as-sigbus.patch queue-4.9/powerpc-don-t-try-to-fix-up-misaligned-load-with-reservation-instructions.patch queue-4.9/mips-lantiq-fix-missing-xbar-kernel-panic.patch queue-4.9/metag-usercopy-zero-rest-of-buffer-from-copy_from_user.patch queue-4.9/xfs-honor-falloc_fl_keep_size-when-punching-ends-of-files.patch queue-4.9/metag-usercopy-fix-alignment-error-checking.patch queue-4.9/reset-treeid-to-zero-on-smb2-tree_connect.patch queue-4.9/documentation-stable-kernel-rules-fix-stable-tag-format.patch queue-4.9/mm-mempolicy.c-fix-error-handling-in-set_mempolicy-and-mbind.patch queue-4.9/arm-arm64-kvm-take-mmap_sem-in-stage2_unmap_vm.patch queue-4.9/mm-page_alloc.c-fix-print-order-in-show_free_areas.patch queue-4.9/hid-usbhid-add-quirks-for-mayflash-dragonrise-gamecube-and-ps3-adapters.patch queue-4.9/mips-c-r4k-fix-loongson-3-s-vcache-scache-waysize-calculation.patch queue-4.9/drm-vmwgfx-avoid-calling-vzalloc-with-a-0-size-in-vmw_get_cap_3d_ioctl.patch queue-4.9/mips-force-o32-fp64-support-on-32bit-mips64r6-kernels.patch queue-4.9/mips-add-mips_cpu_ftlb-for-loongson-3a-r2.patch queue-4.9/kbuild-use-cc-disable-warning-consistently-for-maybe-uninitialized.patch queue-4.9/ppdev-fix-registering-same-device-name.patch queue-4.9/drm-ttm-drm-vmwgfx-relax-permission-checking-when-opening-surfaces.patch queue-4.9/drm-vmwgfx-null-pointer-dereference-in-vmw_surface_define_ioctl.patch