/* * ISA DMA support functions * Copyright (c) by Jaroslav Kysela * * * 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 * */ /* * Defining following add some delay. Maybe this helps for some broken * ISA DMA controllers. */ #undef HAVE_REALLY_SLOW_DMA_CONTROLLER #include #include #include /** * snd_dma_program - program an ISA DMA transfer * @dma: the dma number * @addr: the physical address of the buffer * @size: the DMA transfer size * @mode: the DMA transfer mode, DMA_MODE_XXX * * Programs an ISA DMA transfer for the given buffer. */ void snd_dma_program(unsigned long dma, unsigned long addr, unsigned int size, unsigned short mode) { unsigned long flags; flags = claim_dma_lock(); disable_dma(dma); clear_dma_ff(dma); set_dma_mode(dma, mode); set_dma_addr(dma, addr); set_dma_count(dma, size); if (!(mode & DMA_MODE_NO_ENABLE)) enable_dma(dma); release_dma_lock(flags); } EXPORT_SYMBOL(snd_dma_program); /** * snd_dma_disable - stop the ISA DMA transfer * @dma: the dma number * * Stops the ISA DMA transfer. */ void snd_dma_disable(unsigned long dma) { unsigned long flags; flags = claim_dma_lock(); clear_dma_ff(dma); disable_dma(dma); release_dma_lock(flags); } EXPORT_SYMBOL(snd_dma_disable); /** * snd_dma_pointer - return the current pointer to DMA transfer buffer in bytes * @dma: the dma number * @size: the dma transfer size * * Return: The current pointer in DMA transfer buffer in bytes. */ unsigned int snd_dma_pointer(unsigned long dma, unsigned int size) { unsigned long flags; unsigned int result, result1; flags = claim_dma_lock(); clear_dma_ff(dma); if (!isa_dma_bridge_buggy) disable_dma(dma); result = get_dma_residue(dma); /* * HACK - read the counter again and choose higher value in order to * avoid reading during counter lower byte roll over if the * isa_dma_bridge_buggy is set. */ result1 = get_dma_residue(dma); if (!isa_dma_bridge_buggy) enable_dma(dma); release_dma_lock(flags); if (unlikely(result < result1)) result = result1; #ifdef CONFIG_SND_DEBUG if (result > size) pr_err("ALSA: pointer (0x%x) for DMA #%ld is greater than transfer size (0x%x)\n", result, dma, size); #endif if (result >= size || result == 0) return 0; else return size - result; } EXPORT_SYMBOL(snd_dma_pointer); net-next.git/commit/include/dt-bindings?id=d7df2443cd5f67fc6ee7c05a88e4996e8177f91b'>dt-bindings/reset/qcom,mmcc-msm8974.h
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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2017-02-03 17:10:28 +1100
committerMichael Ellerman <mpe@ellerman.id.au>2017-02-08 23:36:29 +1100
commitd7df2443cd5f67fc6ee7c05a88e4996e8177f91b (patch)
tree098a7c0ca4fceb8a65cb1f693c9d71990388933d /include/dt-bindings/reset/qcom,mmcc-msm8974.h
parenta0615a16f7d0ceb5804d295203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'include/dt-bindings/reset/qcom,mmcc-msm8974.h')