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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/arm/mm/cache-v7m.S
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'arch/arm/mm/cache-v7m.S')
-rw-r--r--arch/arm/mm/cache-v7m.S456
1 files changed, 456 insertions, 0 deletions
diff --git a/arch/arm/mm/cache-v7m.S b/arch/arm/mm/cache-v7m.S
new file mode 100644
index 000000000..eb60b5e5e
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+++ b/arch/arm/mm/cache-v7m.S
@@ -0,0 +1,456 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/mm/cache-v7m.S
+ *
+ * Based on linux/arch/arm/mm/cache-v7.S
+ *
+ * Copyright (C) 2001 Deep Blue Solutions Ltd.
+ * Copyright (C) 2005 ARM Ltd.
+ *
+ * This is the "shell" of the ARMv7M processor support.
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+#include <asm/unwind.h>
+#include <asm/v7m.h>
+
+#include "proc-macros.S"
+
+.arch armv7-m
+
+/* Generic V7M read/write macros for memory mapped cache operations */
+.macro v7m_cache_read, rt, reg
+ movw \rt, #:lower16:BASEADDR_V7M_SCB + \reg
+ movt \rt, #:upper16:BASEADDR_V7M_SCB + \reg
+ ldr \rt, [\rt]
+.endm
+
+.macro v7m_cacheop, rt, tmp, op, c = al
+ movw\c \tmp, #:lower16:BASEADDR_V7M_SCB + \op
+ movt\c \tmp, #:upper16:BASEADDR_V7M_SCB + \op
+ str\c \rt, [\tmp]
+.endm
+
+
+.macro read_ccsidr, rt
+ v7m_cache_read \rt, V7M_SCB_CCSIDR
+.endm
+
+.macro read_clidr, rt
+ v7m_cache_read \rt, V7M_SCB_CLIDR
+.endm
+
+.macro write_csselr, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_CSSELR
+.endm
+
+/*
+ * dcisw: Invalidate data cache by set/way
+ */
+.macro dcisw, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCISW
+.endm
+
+/*
+ * dccisw: Clean and invalidate data cache by set/way
+ */
+.macro dccisw, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCCISW
+.endm
+
+/*
+ * dccimvac: Clean and invalidate data cache line by MVA to PoC.
+ */
+.irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
+.macro dccimvac\c, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCCIMVAC, \c
+.endm
+.endr
+
+/*
+ * dcimvac: Invalidate data cache line by MVA to PoC
+ */
+.irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
+.macro dcimvac\c, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCIMVAC, \c
+.endm
+.endr
+
+/*
+ * dccmvau: Clean data cache line by MVA to PoU
+ */
+.macro dccmvau, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCCMVAU
+.endm
+
+/*
+ * dccmvac: Clean data cache line by MVA to PoC
+ */
+.macro dccmvac, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_DCCMVAC
+.endm
+
+/*
+ * icimvau: Invalidate instruction caches by MVA to PoU
+ */
+.macro icimvau, rt, tmp
+ v7m_cacheop \rt, \tmp, V7M_SCB_ICIMVAU
+.endm
+
+/*
+ * Invalidate the icache, inner shareable if SMP, invalidate BTB for UP.
+ * rt data ignored by ICIALLU(IS), so can be used for the address
+ */
+.macro invalidate_icache, rt
+ v7m_cacheop \rt, \rt, V7M_SCB_ICIALLU
+ mov \rt, #0
+.endm
+
+/*
+ * Invalidate the BTB, inner shareable if SMP.
+ * rt data ignored by BPIALL, so it can be used for the address
+ */
+.macro invalidate_bp, rt
+ v7m_cacheop \rt, \rt, V7M_SCB_BPIALL
+ mov \rt, #0
+.endm
+
+ENTRY(v7m_invalidate_l1)
+ mov r0, #0
+
+ write_csselr r0, r1
+ read_ccsidr r0
+
+ movw r1, #0x7fff
+ and r2, r1, r0, lsr #13
+
+ movw r1, #0x3ff
+
+ and r3, r1, r0, lsr #3 @ NumWays - 1
+ add r2, r2, #1 @ NumSets
+
+ and r0, r0, #0x7
+ add r0, r0, #4 @ SetShift
+
+ clz r1, r3 @ WayShift
+ add r4, r3, #1 @ NumWays
+1: sub r2, r2, #1 @ NumSets--
+ mov r3, r4 @ Temp = NumWays
+2: subs r3, r3, #1 @ Temp--
+ mov r5, r3, lsl r1
+ mov r6, r2, lsl r0
+ orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
+ dcisw r5, r6
+ bgt 2b
+ cmp r2, #0
+ bgt 1b
+ dsb st
+ isb
+ ret lr
+ENDPROC(v7m_invalidate_l1)
+
+/*
+ * v7m_flush_icache_all()
+ *
+ * Flush the whole I-cache.
+ *
+ * Registers:
+ * r0 - set to 0
+ */
+ENTRY(v7m_flush_icache_all)
+ invalidate_icache r0
+ ret lr
+ENDPROC(v7m_flush_icache_all)
+
+/*
+ * v7m_flush_dcache_all()
+ *
+ * Flush the whole D-cache.
+ *
+ * Corrupted registers: r0-r7, r9-r11
+ */
+ENTRY(v7m_flush_dcache_all)
+ dmb @ ensure ordering with previous memory accesses
+ read_clidr r0
+ mov r3, r0, lsr #23 @ move LoC into position
+ ands r3, r3, #7 << 1 @ extract LoC*2 from clidr
+ beq finished @ if loc is 0, then no need to clean
+start_flush_levels:
+ mov r10, #0 @ start clean at cache level 0
+flush_levels:
+ add r2, r10, r10, lsr #1 @ work out 3x current cache level
+ mov r1, r0, lsr r2 @ extract cache type bits from clidr
+ and r1, r1, #7 @ mask of the bits for current cache only
+ cmp r1, #2 @ see what cache we have at this level
+ blt skip @ skip if no cache, or just i-cache
+#ifdef CONFIG_PREEMPTION
+ save_and_disable_irqs_notrace r9 @ make cssr&csidr read atomic
+#endif
+ write_csselr r10, r1 @ set current cache level
+ isb @ isb to sych the new cssr&csidr
+ read_ccsidr r1 @ read the new csidr
+#ifdef CONFIG_PREEMPTION
+ restore_irqs_notrace r9
+#endif
+ and r2, r1, #7 @ extract the length of the cache lines
+ add r2, r2, #4 @ add 4 (line length offset)
+ movw r4, #0x3ff
+ ands r4, r4, r1, lsr #3 @ find maximum number on the way size
+ clz r5, r4 @ find bit position of way size increment
+ movw r7, #0x7fff
+ ands r7, r7, r1, lsr #13 @ extract max number of the index size
+loop1:
+ mov r9, r7 @ create working copy of max index
+loop2:
+ lsl r6, r4, r5
+ orr r11, r10, r6 @ factor way and cache number into r11
+ lsl r6, r9, r2
+ orr r11, r11, r6 @ factor index number into r11
+ dccisw r11, r6 @ clean/invalidate by set/way
+ subs r9, r9, #1 @ decrement the index
+ bge loop2
+ subs r4, r4, #1 @ decrement the way
+ bge loop1
+skip:
+ add r10, r10, #2 @ increment cache number
+ cmp r3, r10
+ bgt flush_levels
+finished:
+ mov r10, #0 @ switch back to cache level 0
+ write_csselr r10, r3 @ select current cache level in cssr
+ dsb st
+ isb
+ ret lr
+ENDPROC(v7m_flush_dcache_all)
+
+/*
+ * v7m_flush_cache_all()
+ *
+ * Flush the entire cache system.
+ * The data cache flush is now achieved using atomic clean / invalidates
+ * working outwards from L1 cache. This is done using Set/Way based cache
+ * maintenance instructions.
+ * The instruction cache can still be invalidated back to the point of
+ * unification in a single instruction.
+ *
+ */
+ENTRY(v7m_flush_kern_cache_all)
+ stmfd sp!, {r4-r7, r9-r11, lr}
+ bl v7m_flush_dcache_all
+ invalidate_icache r0
+ ldmfd sp!, {r4-r7, r9-r11, lr}
+ ret lr
+ENDPROC(v7m_flush_kern_cache_all)
+
+/*
+ * v7m_flush_cache_all()
+ *
+ * Flush all TLB entries in a particular address space
+ *
+ * - mm - mm_struct describing address space
+ */
+ENTRY(v7m_flush_user_cache_all)
+ /*FALLTHROUGH*/
+
+/*
+ * v7m_flush_cache_range(start, end, flags)
+ *
+ * Flush a range of TLB entries in the specified address space.
+ *
+ * - start - start address (may not be aligned)
+ * - end - end address (exclusive, may not be aligned)
+ * - flags - vm_area_struct flags describing address space
+ *
+ * It is assumed that:
+ * - we have a VIPT cache.
+ */
+ENTRY(v7m_flush_user_cache_range)
+ ret lr
+ENDPROC(v7m_flush_user_cache_all)
+ENDPROC(v7m_flush_user_cache_range)
+
+/*
+ * v7m_coherent_kern_range(start,end)
+ *
+ * Ensure that the I and D caches are coherent within specified
+ * region. This is typically used when code has been written to
+ * a memory region, and will be executed.
+ *
+ * - start - virtual start address of region
+ * - end - virtual end address of region
+ *
+ * It is assumed that:
+ * - the Icache does not read data from the write buffer
+ */
+ENTRY(v7m_coherent_kern_range)
+ /* FALLTHROUGH */
+
+/*
+ * v7m_coherent_user_range(start,end)
+ *
+ * Ensure that the I and D caches are coherent within specified
+ * region. This is typically used when code has been written to
+ * a memory region, and will be executed.
+ *
+ * - start - virtual start address of region
+ * - end - virtual end address of region
+ *
+ * It is assumed that:
+ * - the Icache does not read data from the write buffer
+ */
+ENTRY(v7m_coherent_user_range)
+ UNWIND(.fnstart )
+ dcache_line_size r2, r3
+ sub r3, r2, #1
+ bic r12, r0, r3
+1:
+/*
+ * We use open coded version of dccmvau otherwise USER() would
+ * point at movw instruction.
+ */
+ dccmvau r12, r3
+ add r12, r12, r2
+ cmp r12, r1
+ blo 1b
+ dsb ishst
+ icache_line_size r2, r3
+ sub r3, r2, #1
+ bic r12, r0, r3
+2:
+ icimvau r12, r3
+ add r12, r12, r2
+ cmp r12, r1
+ blo 2b
+ invalidate_bp r0
+ dsb ishst
+ isb
+ ret lr
+ UNWIND(.fnend )
+ENDPROC(v7m_coherent_kern_range)
+ENDPROC(v7m_coherent_user_range)
+
+/*
+ * v7m_flush_kern_dcache_area(void *addr, size_t size)
+ *
+ * Ensure that the data held in the page kaddr is written back
+ * to the page in question.
+ *
+ * - addr - kernel address
+ * - size - region size
+ */
+ENTRY(v7m_flush_kern_dcache_area)
+ dcache_line_size r2, r3
+ add r1, r0, r1
+ sub r3, r2, #1
+ bic r0, r0, r3
+1:
+ dccimvac r0, r3 @ clean & invalidate D line / unified line
+ add r0, r0, r2
+ cmp r0, r1
+ blo 1b
+ dsb st
+ ret lr
+ENDPROC(v7m_flush_kern_dcache_area)
+
+/*
+ * v7m_dma_inv_range(start,end)
+ *
+ * Invalidate the data cache within the specified region; we will
+ * be performing a DMA operation in this region and we want to
+ * purge old data in the cache.
+ *
+ * - start - virtual start address of region
+ * - end - virtual end address of region
+ */
+v7m_dma_inv_range:
+ dcache_line_size r2, r3
+ sub r3, r2, #1
+ tst r0, r3
+ bic r0, r0, r3
+ dccimvacne r0, r3
+ addne r0, r0, r2
+ subne r3, r2, #1 @ restore r3, corrupted by v7m's dccimvac
+ tst r1, r3
+ bic r1, r1, r3
+ dccimvacne r1, r3
+ cmp r0, r1
+1:
+ dcimvaclo r0, r3
+ addlo r0, r0, r2
+ cmplo r0, r1
+ blo 1b
+ dsb st
+ ret lr
+ENDPROC(v7m_dma_inv_range)
+
+/*
+ * v7m_dma_clean_range(start,end)
+ * - start - virtual start address of region
+ * - end - virtual end address of region
+ */
+v7m_dma_clean_range:
+ dcache_line_size r2, r3
+ sub r3, r2, #1
+ bic r0, r0, r3
+1:
+ dccmvac r0, r3 @ clean D / U line
+ add r0, r0, r2
+ cmp r0, r1
+ blo 1b
+ dsb st
+ ret lr
+ENDPROC(v7m_dma_clean_range)
+
+/*
+ * v7m_dma_flush_range(start,end)
+ * - start - virtual start address of region
+ * - end - virtual end address of region
+ */
+ENTRY(v7m_dma_flush_range)
+ dcache_line_size r2, r3
+ sub r3, r2, #1
+ bic r0, r0, r3
+1:
+ dccimvac r0, r3 @ clean & invalidate D / U line
+ add r0, r0, r2
+ cmp r0, r1
+ blo 1b
+ dsb st
+ ret lr
+ENDPROC(v7m_dma_flush_range)
+
+/*
+ * dma_map_area(start, size, dir)
+ * - start - kernel virtual start address
+ * - size - size of region
+ * - dir - DMA direction
+ */
+ENTRY(v7m_dma_map_area)
+ add r1, r1, r0
+ teq r2, #DMA_FROM_DEVICE
+ beq v7m_dma_inv_range
+ b v7m_dma_clean_range
+ENDPROC(v7m_dma_map_area)
+
+/*
+ * dma_unmap_area(start, size, dir)
+ * - start - kernel virtual start address
+ * - size - size of region
+ * - dir - DMA direction
+ */
+ENTRY(v7m_dma_unmap_area)
+ add r1, r1, r0
+ teq r2, #DMA_TO_DEVICE
+ bne v7m_dma_inv_range
+ ret lr
+ENDPROC(v7m_dma_unmap_area)
+
+ .globl v7m_flush_kern_cache_louis
+ .equ v7m_flush_kern_cache_louis, v7m_flush_kern_cache_all
+
+ __INITDATA
+
+ @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
+ define_cache_functions v7m