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2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174Thomas Gleixner1-9/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-26iommu/mediatek: Fix leaked of_node referencesWen Yang1-2/+6
The call to of_parse_phandle returns a node pointer with refcount incremented thus it must be explicitly decremented after the last usage. 581 static int mtk_iommu_probe(struct platform_device *pdev) 582 { ... 626 for (i = 0; i < larb_nr; i++) { 627 struct device_node *larbnode; ... 631 larbnode = of_parse_phandle(...); 632 if (!larbnode) 633 return -EINVAL; 634 635 if (!of_device_is_available(larbnode)) 636 continue; ---> leaked here 637 ... 643 if (!plarbdev) 644 return -EPROBE_DEFER; ---> leaked here ... 647 component_match_add_release(dev, &match, release_of, 648 compare_of, larbnode); ---> release_of will call of_node_put 649 } ... 650 Detected by coccinelle with the following warnings: ./drivers/iommu/mtk_iommu.c:644:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 631, but without a corresponding object release within this function. Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> Cc: Joerg Roedel <joro@8bytes.org> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: iommu@lists.linux-foundation.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mediatek@lists.infradead.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Matthias Brugger <mbrugger@suse.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-12-20Merge branches 'iommu/fixes', 'arm/renesas', 'arm/mediatek', 'arm/tegra', ↵Joerg Roedel1-11/+14
'arm/omap', 'arm/smmu', 'x86/vt-d', 'x86/amd' and 'core' into next
2018-12-17iommu/mediatek: Use helper functions to access dev->iommu_fwspecJoerg Roedel1-9/+12
Use the new helpers dev_iommu_fwspec_get()/set() to access the dev->iommu_fwspec pointer. This makes it easier to move that pointer later into another struct. Cc: Matthias Brugger <matthias.bgg@gmail.com> Tested-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-11-06iommu/mediatek: Constify iommu_opsArvind Yadav1-2/+2
iommu_ops are not supposed to change at runtime. Functions 'iommu_device_set_ops' and 'bus_set_iommu' working with const iommu_ops provided by <linux/iommu.h>. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> (Change the title to iommu/mediatek: xx) Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-10-31mm: remove include/linux/bootmem.hMike Rapoport1-1/+1
Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-08iommu: Remove the ->map_sg indirectionChristoph Hellwig1-1/+0
All iommu drivers use the default_iommu_map_sg implementation, and there is no good reason to ever override it. Just expose it as iommu_map_sg directly and remove the indirection, specially in our post-spectre world where indirect calls are horribly expensive. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-03-21iommu/mediatek: Fix protect memory settingYong Wu1-5/+10
In MediaTek's IOMMU design, When a iommu translation fault occurs (HW can NOT translate the destination address to a valid physical address), the IOMMU HW output the dirty data into a special memory to avoid corrupting the main memory, this is called "protect memory". the register(0x114) for protect memory is a little different between mt8173 and mt2712. In the mt8173, bit[30:6] in the register represents [31:7] of the physical address. In the 4GB mode, the register bit[31] should be 1. While in the mt2712, the bits don't shift. bit[31:7] in the register represents [31:7] in the physical address, and bit[1:0] in the register represents bit[33:32] of the physical address if it has. Fixes: e6dec9230862 ("iommu/mediatek: Add mt2712 IOMMU support") Reported-by: Honghui Zhang <honghui.zhang@mediatek.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-10-13Merge branches 'iommu/fixes', 'arm/omap', 'arm/exynos', 'x86/amd', ↵Joerg Roedel1-0/+7
'x86/vt-d' and 'core' into next
2017-10-02iommu/io-pgtable-arm-v7s: Convert to IOMMU API TLB syncRobin Murphy1-0/+7
Now that the core API issues its own post-unmap TLB sync call, push that operation out from the io-pgtable-arm-v7s internals into the users. For now, we leave the invalidation implicit in the unmap operation, since none of the current users would benefit much from any change to that. Note that the conversion of msm_iommu is implicit, since that apparently has no specific TLB sync operation anyway. CC: Yong Wu <yong.wu@mediatek.com> CC: Rob Clark <robdclark@gmail.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-09-27iommu/mediatek: Limit the physical address in 32bit for v7sYong Wu1-1/+2
The ARM short descriptor has already limited the physical address to 32bit after the commit <76557391433c> ("iommu/io-pgtable: Sanitise map/unmap addresses"). But in MediaTek 4GB mode, the physical address is from 0x1_0000_0000 to 0x1_ffff_ffff. this will cause: WARNING: CPU: 4 PID: 3900 at xxx/drivers/iommu/io-pgtable-arm-v7s.c:482 arm_v7s_map+0x40/0xf8 Modules linked in: CPU: 4 PID: 3900 Comm: weston Tainted: G S W 4.9.44 #1 Hardware name: MediaTek MT2712m1v1 board (DT) task: ffffffc0eaa5b280 task.stack: ffffffc0e9858000 PC is at arm_v7s_map+0x40/0xf8 LR is at mtk_iommu_map+0x64/0x90 pc : [<ffffff80085b09e8>] lr : [<ffffff80085b29fc>] pstate: 000001c5 sp : ffffffc0e985b920 x29: ffffffc0e985b920 x28: 0000000127d00000 x27: 0000000000100000 x26: ffffff8008f9e000 x25: 0000000000000003 x24: 0000000000100000 x23: 0000000127d00000 x22: 00000000ff800000 x21: ffffffc0f7ec8ce0 x20: 0000000000000003 x19: 0000000000000003 x18: 0000000000000002 x17: 0000007f7e5d72c0 x16: ffffff80082b0f08 x15: 0000000000000001 x14: 000000000000003f x13: 0000000000000000 x12: 0000000000000028 x11: 0088000000000000 x10: 0000000000000000 x9 : ffffff80092fa000 x8 : ffffffc0e9858000 x7 : ffffff80085b29d8 x6 : 0000000000000000 x5 : ffffff80085b09a8 x4 : 0000000000000003 x3 : 0000000000100000 x2 : 0000000127d00000 x1 : 00000000ff800000 x0 : 0000000000000001 ... Call trace: [<ffffff80085b09e8>] arm_v7s_map+0x40/0xf8 [<ffffff80085b29fc>] mtk_iommu_map+0x64/0x90 [<ffffff80085ab5f8>] iommu_map+0x100/0x3a0 [<ffffff80085ab99c>] default_iommu_map_sg+0x104/0x168 [<ffffff80085aead8>] iommu_dma_alloc+0x238/0x3f8 [<ffffff8008098b30>] __iommu_alloc_attrs+0xa8/0x260 [<ffffff80085f364c>] mtk_drm_gem_create+0xac/0x180 [<ffffff80085f3894>] mtk_drm_gem_dumb_create+0x54/0xc8 [<ffffff80085d576c>] drm_mode_create_dumb_ioctl+0xa4/0xd8 [<ffffff80085cb2a0>] drm_ioctl+0x1c0/0x490 In order to satify this, Limit the physical address to 32bit. Signed-off-by: Yong Wu <yong.wu@mediatek.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-28iommu/mediatek: Fix a build warning of BIT(32) in ARMYong Wu1-2/+2
The commit ("iommu/mediatek: Enlarge the validate PA range for 4GB mode") introduce the following build warning while ARCH=arm: drivers/iommu/mtk_iommu.c: In function 'mtk_iommu_iova_to_phys': include/linux/bitops.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow] #define BIT(nr) (1UL << (nr)) ^ >> drivers/iommu/mtk_iommu.c:407:9: note: in expansion of macro 'BIT' pa |= BIT(32); drivers/iommu/mtk_iommu.c: In function 'mtk_iommu_probe': include/linux/bitops.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow] #define BIT(nr) (1UL << (nr)) ^ drivers/iommu/mtk_iommu.c:589:35: note: in expansion of macro 'BIT' data->enable_4GB = !!(max_pfn > (BIT(32) >> PAGE_SHIFT)); Use BIT_ULL instead of BIT. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-28iommu/mediatek: Fix a build fail of m4u_typeYong Wu1-1/+1
The commit ("iommu/mediatek: Enlarge the validate PA range for 4GB mode") introduce the following build error: drivers/iommu/mtk_iommu.c: In function 'mtk_iommu_hw_init': >> drivers/iommu/mtk_iommu.c:536:30: error: 'const struct mtk_iommu_data' has no member named 'm4u_type'; did you mean 'm4u_dom'? if (data->enable_4GB && data->m4u_type != M4U_MT8173) { This patch fix it, use "m4u_plat" instead of "m4u_type". Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-22iommu/mediatek: Enlarge the validate PA range for 4GB modeYong Wu1-3/+15
This patch is for 4GB mode, mainly for 4 issues: 1) Fix a 4GB bug: if the dram base is 0x4000_0000, the dram size is 0xc000_0000. then the code just meet a corner case because max_pfn is 0x10_0000. data->enable_4GB = !!(max_pfn > (0xffffffffUL >> PAGE_SHIFT)); It's true at the case above. That is unexpected. 2) In mt2712, there is a new register for the 4GB PA range(0x118) we should enlarge the max PA range, or the HW will report error. The dram range is from 0x1_0000_0000 to 0x1_ffff_ffff in the 4GB mode, we cut out the bit[32:30] of the SA(Start address) and EA(End address) into this REG_MMU_VLD_PA_RNG(0x118). 3) In mt2712, the register(0x13c) is extended for 4GB mode. bit[7:6] indicate the valid PA[32:33]. Thus, we don't mask the value and print it directly for debug. 4) if 4GB is enabled, the dram PA range is from 0x1_0000_0000 to 0x1_ffff_ffff. Thus, the PA from iova_to_pa should also '|' BIT(32) Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-22iommu/mediatek: Disable iommu clock when system suspendYong Wu1-1/+8
When system suspend, infra power domain may be off, and the iommu's clock must be disabled when system off, or the iommu's bclk clock maybe disabled after system resume. Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-22iommu/mediatek: Move pgtable allocation into domain_allocYong Wu1-30/+22
After adding the global list for M4U HW, We get a chance to move the pagetable allocation into the mtk_iommu_domain_alloc. Let the domain_alloc do the right thing. This patch is for fixing this problem[1]. [1]: https://patchwork.codeaurora.org/patch/53987/ Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-22iommu/mediatek: Merge 2 M4U HWs into one iommu domainYong Wu1-24/+68
In theory, If there are 2 M4U HWs, there should be 2 IOMMU domains. But one IOMMU domain(4GB iova range) is enough for us currently, It's unnecessary to maintain 2 pagetables. Besides, This patch can simplify our consumer code largely. They don't need map a iova range from one domain into another, They can share the iova address easily. Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-22iommu/mediatek: Add mt2712 IOMMU supportYong Wu1-37/+34
The M4U IP blocks in mt2712 is MTK's generation2 M4U which use the ARM Short-descriptor like mt8173, and most of the HW registers are the same. The difference is that there are 2 M4U HWs in mt2712 while there's only one in mt8173. The purpose of 2 M4U HWs is for balance the bandwidth. Normally if there are 2 M4U HWs, there should be 2 iommu domains, each M4U has a iommu domain. Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-22iommu/mediatek: Move MTK_M4U_TO_LARB/PORT into mtk_iommu.cYong Wu1-1/+7
The definition of MTK_M4U_TO_LARB and MTK_M4U_TO_PORT are shared by all the gen2 M4U HWs. Thus, Move them out from mt8173-larb-port.h, and put them into the c file. Suggested-by: Honghui Zhang <honghui.zhang@mediatek.com> Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-07-20iommu/mtk: Avoid redundant TLB syncs locallyRobin Murphy1-0/+6
Under certain circumstances, the io-pgtable code may end up issuing two TLB sync operations without any intervening invalidations. This goes badly for the M4U hardware, since it means the second sync ends up polling for a non-existent operation to finish, and as a result times out and warns. The io_pgtable_tlb_* helpers implement a high-level optimisation to avoid issuing the second sync at all in such cases, but in order to work correctly that requires all pagetable operations to be serialised under a lock, thus is no longer applicable to all io-pgtable users. Since we're the only user actually relying on this flag for correctness, let's reimplement it locally to avoid the headache of trying to make the high-level version concurrency-safe for other users. CC: Yong Wu <yong.wu@mediatek.com> CC: Matthias Brugger <matthias.bgg@gmail.com> Tested-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-10iommu: Remove iommu_register_instance interfaceJoerg Roedel1-1/+0
And also move its remaining functionality to iommu_device_register() and 'struct iommu_device'. Cc: Rob Herring <robh+dt@kernel.org> Cc: Frank Rowand <frowand.list@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: devicetree@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-02-10iommu/mediatek: Make use of iommu_device_register interfaceJoerg Roedel1-0/+26
Register individual Mediatek IOMMUs to the iommu core and add sysfs entries. Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mediatek@lists.infradead.org Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-12-06Merge branches 'arm/mediatek', 'arm/smmu', 'x86/amd', 's390', 'core' and ↵Joerg Roedel1-60/+25
'arm/exynos' into next
2016-11-15iommu/mediatek: Fix M4Uv2 group refcountingRobin Murphy1-0/+2
For each subsequent device assigned to the m4u_group after its initial allocation, we need to take an additional reference. Otherwise, the caller of iommu_group_get_for_dev() will inadvertently remove the reference taken by iommu_group_add_device(), and the group will be freed prematurely if any device is removed. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-11-10iommu/mediatek: Convert DT component matching to component_match_add_release()Russell King1-3/+5
Convert DT component matching to use component_match_add_release(). Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-11-10iommu/mediatek: Convert M4Uv2 to iommu_fwspecRobin Murphy1-57/+18
Our per-device data consists of the M4U instance and firmware-provided list of LARB IDs, which is a perfect fit for the generic iommu_fwspec machinery. Use that directly as a simpler alternative to the custom archdata code. CC: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-06-21iommu/mediatek: move the common struct into header fileHonghui Zhang1-47/+1
Move the struct defines of mtk iommu into a new header files for common use. Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-06-21iommu/mediatek: Do not call of_node_put in mtk_iommu_of_xlateHonghui Zhang1-1/+0
The device_node will be released in of_iommu_configure, it may be double released if call of_node_put in mtk_iommu_of_xlate. Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-05-09Merge branches 'arm/io-pgtable', 'arm/rockchip', 'arm/omap', 'x86/vt-d', ↵Joerg Roedel1-1/+1
'ppc/pamu', 'core' and 'x86/amd' into next
2016-05-09iommu: Allow selecting page sizes per domainRobin Murphy1-1/+1
Many IOMMUs support multiple page table formats, meaning that any given domain may only support a subset of the hardware page sizes presented in iommu_ops->pgsize_bitmap. There are also certain use-cases where the creator of a domain may want to control which page sizes are used, for example to force the use of hugepage mappings to reduce pagetable walk depth. To this end, add a per-domain pgsize_bitmap to represent the subset of page sizes actually in use, to make it possible for domains with different requirements to coexist. Signed-off-by: Will Deacon <will.deacon@arm.com> [rm: hijacked and rebased original patch with new commit message] Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-05iommu/mediatek: Add 4GB mode supportYong Wu1-3/+11
This patch add 4GB mode support for m4u. Signed-off-by: Yong Wu <yong.wu@mediatek.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-03-02iommu/mediatek: Check for NULL instead of IS_ERR()Dan Carpenter1-3/+3
of_platform_device_create() returns NULL on error, it never returns error pointers. Fixes: 0df4fabe208d ('iommu/mediatek: Add mt8173 IOMMU driver') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-03-01iommu/mediatek: Fix handling of of_count_phandle_with_args resultAndrzej Hajda1-2/+1
The function can return negative value so it should be assigned to signed variable. The patch changes also type of related i variable to make code more compact and coherent. The problem has been detected using patch scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci. Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-02-29iommu/mediatek: Mark PM functions as __maybe_unusedArnd Bergmann1-2/+2
When CONFIG_PM is unset, we get a harmless warning for this driver: drivers/iommu/mtk_iommu.c:665:12: error: 'mtk_iommu_suspend' defined but not used [-Werror=unused-function] drivers/iommu/mtk_iommu.c:680:12: error: 'mtk_iommu_resume' defined but not used [-Werror=unused-function] Marking the functions as __maybe_unused gits rid of the two functions and lets the compiler silently drop the object code, while still doing syntax checking on them for build-time verification. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 0df4fabe208d ("iommu/mediatek: Add mt8173 IOMMU driver") Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-02-25iommu/mediatek: Add mt8173 IOMMU driverYong Wu1-0/+737
This patch adds support for mediatek m4u (MultiMedia Memory Management Unit). Signed-off-by: Yong Wu <yong.wu@mediatek.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>