/* * Power management for audio on multifunction CS5535 companion device * Copyright (C) Jaya Kumar * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include #include #include #include #include #include #include #include #include #include "cs5535audio.h" static void snd_cs5535audio_stop_hardware(struct cs5535audio *cs5535au) { /* we depend on snd_ac97_suspend to tell the AC97 codec to shutdown. the amd spec suggests that the LNK_SHUTDOWN be done at the same time that the codec power-down is issued. instead, we do it just after rather than at the same time. excluding codec specific build_ops->suspend ac97 powerdown hits: 0x8000 EAPD 0x4000 Headphone amplifier 0x0300 ADC & DAC 0x0400 Analog Mixer powerdown (Vref on) I am not sure if this is the best that we can do. The remainder to be investigated are: - analog mixer (vref off) 0x0800 - AC-link powerdown 0x1000 - codec internal clock 0x2000 */ /* set LNK_SHUTDOWN to shutdown AC link */ cs_writel(cs5535au, ACC_CODEC_CNTL, ACC_CODEC_CNTL_LNK_SHUTDOWN); } static int snd_cs5535audio_suspend(struct device *dev) { struct snd_card *card = dev_get_drvdata(dev); struct cs5535audio *cs5535au = card->private_data; int i; snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); snd_pcm_suspend_all(cs5535au->pcm); snd_ac97_suspend(cs5535au->ac97); for (i = 0; i < NUM_CS5535AUDIO_DMAS; i++) { struct cs5535audio_dma *dma = &cs5535au->dmas[i]; if (dma && dma->substream) dma->saved_prd = dma->ops->read_prd(cs5535au); } /* save important regs, then disable aclink in hw */ snd_cs5535audio_stop_hardware(cs5535au); return 0; } static int snd_cs5535audio_resume(struct device *dev) { struct snd_card *card = dev_get_drvdata(dev); struct cs5535audio *cs5535au = card->private_data; u32 tmp; int timeout; int i; /* set LNK_WRM_RST to reset AC link */ cs_writel(cs5535au, ACC_CODEC_CNTL, ACC_CODEC_CNTL_LNK_WRM_RST); timeout = 50; do { tmp = cs_readl(cs5535au, ACC_CODEC_STATUS); if (tmp & PRM_RDY_STS) break; udelay(1); } while (--timeout); if (!timeout) dev_err(cs5535au->card->dev, "Failure getting AC Link ready\n"); /* set up rate regs, dma. actual initiation is done in trig */ for (i = 0; i < NUM_CS5535AUDIO_DMAS; i++) { struct cs5535audio_dma *dma = &cs5535au->dmas[i]; if (dma && dma->substream) { dma->substream->ops->prepare(dma->substream); dma->ops->setup_prd(cs5535au, dma->saved_prd); } } /* we depend on ac97 to perform the codec power up */ snd_ac97_resume(cs5535au->ac97); snd_power_change_state(card, SNDRV_CTL_POWER_D0); return 0; } SIMPLE_DEV_PM_OPS(snd_cs5535audio_pm, snd_cs5535audio_suspend, snd_cs5535audio_resume); d='get'>
context:
space:
mode:
authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-02-01 17:45:02 +0000
committerIngo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100
commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch)
treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /tools/testing/selftests/kselftest_install.sh
parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools/testing/selftests/kselftest_install.sh')