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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/powerpc/platforms/52xx/lite5200_sleep.S
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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/powerpc/platforms/52xx/lite5200_sleep.S')
-rw-r--r--arch/powerpc/platforms/52xx/lite5200_sleep.S422
1 files changed, 422 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/52xx/lite5200_sleep.S b/arch/powerpc/platforms/52xx/lite5200_sleep.S
new file mode 100644
index 000000000..0b12647e7
--- /dev/null
+++ b/arch/powerpc/platforms/52xx/lite5200_sleep.S
@@ -0,0 +1,422 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
+
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/processor.h>
+#include <asm/cache.h>
+
+
+#define SDRAM_CTRL 0x104
+#define SC_MODE_EN (1<<31)
+#define SC_CKE (1<<30)
+#define SC_REF_EN (1<<28)
+#define SC_SOFT_PRE (1<<1)
+
+#define GPIOW_GPIOE 0xc00
+#define GPIOW_DDR 0xc08
+#define GPIOW_DVO 0xc0c
+
+#define CDM_CE 0x214
+#define CDM_SDRAM (1<<3)
+
+
+/* helpers... beware: r10 and r4 are overwritten */
+#define SAVE_SPRN(reg, addr) \
+ mfspr r10, SPRN_##reg; \
+ stw r10, ((addr)*4)(r4);
+
+#define LOAD_SPRN(reg, addr) \
+ lwz r10, ((addr)*4)(r4); \
+ mtspr SPRN_##reg, r10; \
+ sync; \
+ isync;
+
+
+ .data
+registers:
+ .space 0x5c*4
+ .text
+
+/* ---------------------------------------------------------------------- */
+/* low-power mode with help of M68HLC908QT1 */
+
+ .globl lite5200_low_power
+lite5200_low_power:
+
+ mr r7, r3 /* save SRAM va */
+ mr r8, r4 /* save MBAR va */
+
+ /* setup wakeup address for u-boot at physical location 0x0 */
+ lis r3, CONFIG_KERNEL_START@h
+ lis r4, lite5200_wakeup@h
+ ori r4, r4, lite5200_wakeup@l
+ sub r4, r4, r3
+ stw r4, 0(r3)
+
+
+ /*
+ * save stuff BDI overwrites
+ * 0xf0 (0xe0->0x100 gets overwritten when BDI connected;
+ * even when CONFIG_BDI_SWITCH is disabled and MMU XLAT commented; heisenbug?))
+ * WARNING: self-refresh doesn't seem to work when BDI2000 is connected,
+ * possibly because BDI sets SDRAM registers before wakeup code does
+ */
+ lis r4, registers@h
+ ori r4, r4, registers@l
+ lwz r10, 0xf0(r3)
+ stw r10, (0x1d*4)(r4)
+
+ /* save registers to r4 [destroys r10] */
+ SAVE_SPRN(LR, 0x1c)
+ bl save_regs
+
+ /* flush caches [destroys r3, r4] */
+ bl flush_data_cache
+
+
+ /* copy code to sram */
+ mr r4, r7
+ li r3, (sram_code_end - sram_code)/4
+ mtctr r3
+ lis r3, sram_code@h
+ ori r3, r3, sram_code@l
+1:
+ lwz r5, 0(r3)
+ stw r5, 0(r4)
+ addi r3, r3, 4
+ addi r4, r4, 4
+ bdnz 1b
+
+ /* get tb_ticks_per_usec */
+ lis r3, tb_ticks_per_usec@h
+ lwz r11, tb_ticks_per_usec@l(r3)
+
+ /* disable I and D caches */
+ mfspr r3, SPRN_HID0
+ ori r3, r3, HID0_ICE | HID0_DCE
+ xori r3, r3, HID0_ICE | HID0_DCE
+ sync; isync;
+ mtspr SPRN_HID0, r3
+ sync; isync;
+
+ /* jump to sram */
+ mtlr r7
+ blrl
+ /* doesn't return */
+
+
+sram_code:
+ /* self refresh */
+ lwz r4, SDRAM_CTRL(r8)
+
+ /* send NOP (precharge) */
+ oris r4, r4, SC_MODE_EN@h /* mode_en */
+ stw r4, SDRAM_CTRL(r8)
+ sync
+
+ ori r4, r4, SC_SOFT_PRE /* soft_pre */
+ stw r4, SDRAM_CTRL(r8)
+ sync
+ xori r4, r4, SC_SOFT_PRE
+
+ xoris r4, r4, SC_MODE_EN@h /* !mode_en */
+ stw r4, SDRAM_CTRL(r8)
+ sync
+
+ /* delay (for NOP to finish) */
+ li r12, 1
+ bl udelay
+
+ /*
+ * mode_en must not be set when enabling self-refresh
+ * send AR with CKE low (self-refresh)
+ */
+ oris r4, r4, (SC_REF_EN | SC_CKE)@h
+ xoris r4, r4, (SC_CKE)@h /* ref_en !cke */
+ stw r4, SDRAM_CTRL(r8)
+ sync
+
+ /* delay (after !CKE there should be two cycles) */
+ li r12, 1
+ bl udelay
+
+ /* disable clock */
+ lwz r4, CDM_CE(r8)
+ ori r4, r4, CDM_SDRAM
+ xori r4, r4, CDM_SDRAM
+ stw r4, CDM_CE(r8)
+ sync
+
+ /* delay a bit */
+ li r12, 1
+ bl udelay
+
+
+ /* turn off with QT chip */
+ li r4, 0x02
+ stb r4, GPIOW_GPIOE(r8) /* enable gpio_wkup1 */
+ sync
+
+ stb r4, GPIOW_DVO(r8) /* "output" high */
+ sync
+ stb r4, GPIOW_DDR(r8) /* output */
+ sync
+ stb r4, GPIOW_DVO(r8) /* output high */
+ sync
+
+ /* 10uS delay */
+ li r12, 10
+ bl udelay
+
+ /* turn off */
+ li r4, 0
+ stb r4, GPIOW_DVO(r8) /* output low */
+ sync
+
+ /* wait until we're offline */
+ 1:
+ b 1b
+
+
+ /* local udelay in sram is needed */
+SYM_FUNC_START_LOCAL(udelay)
+ /* r11 - tb_ticks_per_usec, r12 - usecs, overwrites r13 */
+ mullw r12, r12, r11
+ mftb r13 /* start */
+ add r12, r13, r12 /* end */
+ 1:
+ mftb r13 /* current */
+ cmp cr0, r13, r12
+ blt 1b
+ blr
+SYM_FUNC_END(udelay)
+
+sram_code_end:
+
+
+
+/* uboot jumps here on resume */
+lite5200_wakeup:
+ bl restore_regs
+
+
+ /* HIDs, MSR */
+ LOAD_SPRN(HID1, 0x19)
+ LOAD_SPRN(HID2, 0x1a)
+
+
+ /* address translation is tricky (see turn_on_mmu) */
+ mfmsr r10
+ ori r10, r10, MSR_DR | MSR_IR
+
+
+ mtspr SPRN_SRR1, r10
+ lis r10, mmu_on@h
+ ori r10, r10, mmu_on@l
+ mtspr SPRN_SRR0, r10
+ sync
+ rfi
+mmu_on:
+ /* kernel offset (r4 is still set from restore_registers) */
+ addis r4, r4, CONFIG_KERNEL_START@h
+
+
+ /* restore MSR */
+ lwz r10, (4*0x1b)(r4)
+ mtmsr r10
+ sync; isync;
+
+ /* invalidate caches */
+ mfspr r10, SPRN_HID0
+ ori r5, r10, HID0_ICFI | HID0_DCI
+ mtspr SPRN_HID0, r5 /* invalidate caches */
+ sync; isync;
+ mtspr SPRN_HID0, r10
+ sync; isync;
+
+ /* enable caches */
+ lwz r10, (4*0x18)(r4)
+ mtspr SPRN_HID0, r10 /* restore (enable caches, DPM) */
+ /* ^ this has to be after address translation set in MSR */
+ sync
+ isync
+
+
+ /* restore 0xf0 (BDI2000) */
+ lis r3, CONFIG_KERNEL_START@h
+ lwz r10, (0x1d*4)(r4)
+ stw r10, 0xf0(r3)
+
+ LOAD_SPRN(LR, 0x1c)
+
+
+ blr
+_ASM_NOKPROBE_SYMBOL(lite5200_wakeup)
+
+
+/* ---------------------------------------------------------------------- */
+/* boring code: helpers */
+
+/* save registers */
+#define SAVE_BAT(n, addr) \
+ SAVE_SPRN(DBAT##n##L, addr); \
+ SAVE_SPRN(DBAT##n##U, addr+1); \
+ SAVE_SPRN(IBAT##n##L, addr+2); \
+ SAVE_SPRN(IBAT##n##U, addr+3);
+
+#define SAVE_SR(n, addr) \
+ mfsr r10, n; \
+ stw r10, ((addr)*4)(r4);
+
+#define SAVE_4SR(n, addr) \
+ SAVE_SR(n, addr); \
+ SAVE_SR(n+1, addr+1); \
+ SAVE_SR(n+2, addr+2); \
+ SAVE_SR(n+3, addr+3);
+
+SYM_FUNC_START_LOCAL(save_regs)
+ stw r0, 0(r4)
+ stw r1, 0x4(r4)
+ stw r2, 0x8(r4)
+ stmw r11, 0xc(r4) /* 0xc -> 0x5f, (0x18*4-1) */
+
+ SAVE_SPRN(HID0, 0x18)
+ SAVE_SPRN(HID1, 0x19)
+ SAVE_SPRN(HID2, 0x1a)
+ mfmsr r10
+ stw r10, (4*0x1b)(r4)
+ /*SAVE_SPRN(LR, 0x1c) have to save it before the call */
+ /* 0x1d reserved by 0xf0 */
+ SAVE_SPRN(RPA, 0x1e)
+ SAVE_SPRN(SDR1, 0x1f)
+
+ /* save MMU regs */
+ SAVE_BAT(0, 0x20)
+ SAVE_BAT(1, 0x24)
+ SAVE_BAT(2, 0x28)
+ SAVE_BAT(3, 0x2c)
+ SAVE_BAT(4, 0x30)
+ SAVE_BAT(5, 0x34)
+ SAVE_BAT(6, 0x38)
+ SAVE_BAT(7, 0x3c)
+
+ SAVE_4SR(0, 0x40)
+ SAVE_4SR(4, 0x44)
+ SAVE_4SR(8, 0x48)
+ SAVE_4SR(12, 0x4c)
+
+ SAVE_SPRN(SPRG0, 0x50)
+ SAVE_SPRN(SPRG1, 0x51)
+ SAVE_SPRN(SPRG2, 0x52)
+ SAVE_SPRN(SPRG3, 0x53)
+ SAVE_SPRN(SPRG4, 0x54)
+ SAVE_SPRN(SPRG5, 0x55)
+ SAVE_SPRN(SPRG6, 0x56)
+ SAVE_SPRN(SPRG7, 0x57)
+
+ SAVE_SPRN(IABR, 0x58)
+ SAVE_SPRN(DABR, 0x59)
+ SAVE_SPRN(TBRL, 0x5a)
+ SAVE_SPRN(TBRU, 0x5b)
+
+ blr
+SYM_FUNC_END(save_regs)
+
+
+/* restore registers */
+#define LOAD_BAT(n, addr) \
+ LOAD_SPRN(DBAT##n##L, addr); \
+ LOAD_SPRN(DBAT##n##U, addr+1); \
+ LOAD_SPRN(IBAT##n##L, addr+2); \
+ LOAD_SPRN(IBAT##n##U, addr+3);
+
+#define LOAD_SR(n, addr) \
+ lwz r10, ((addr)*4)(r4); \
+ mtsr n, r10;
+
+#define LOAD_4SR(n, addr) \
+ LOAD_SR(n, addr); \
+ LOAD_SR(n+1, addr+1); \
+ LOAD_SR(n+2, addr+2); \
+ LOAD_SR(n+3, addr+3);
+
+SYM_FUNC_START_LOCAL(restore_regs)
+ lis r4, registers@h
+ ori r4, r4, registers@l
+
+ /* MMU is not up yet */
+ subis r4, r4, CONFIG_KERNEL_START@h
+
+ lwz r0, 0(r4)
+ lwz r1, 0x4(r4)
+ lwz r2, 0x8(r4)
+ lmw r11, 0xc(r4)
+
+ /*
+ * these are a bit tricky
+ *
+ * 0x18 - HID0
+ * 0x19 - HID1
+ * 0x1a - HID2
+ * 0x1b - MSR
+ * 0x1c - LR
+ * 0x1d - reserved by 0xf0 (BDI2000)
+ */
+ LOAD_SPRN(RPA, 0x1e);
+ LOAD_SPRN(SDR1, 0x1f);
+
+ /* restore MMU regs */
+ LOAD_BAT(0, 0x20)
+ LOAD_BAT(1, 0x24)
+ LOAD_BAT(2, 0x28)
+ LOAD_BAT(3, 0x2c)
+ LOAD_BAT(4, 0x30)
+ LOAD_BAT(5, 0x34)
+ LOAD_BAT(6, 0x38)
+ LOAD_BAT(7, 0x3c)
+
+ LOAD_4SR(0, 0x40)
+ LOAD_4SR(4, 0x44)
+ LOAD_4SR(8, 0x48)
+ LOAD_4SR(12, 0x4c)
+
+ /* rest of regs */
+ LOAD_SPRN(SPRG0, 0x50);
+ LOAD_SPRN(SPRG1, 0x51);
+ LOAD_SPRN(SPRG2, 0x52);
+ LOAD_SPRN(SPRG3, 0x53);
+ LOAD_SPRN(SPRG4, 0x54);
+ LOAD_SPRN(SPRG5, 0x55);
+ LOAD_SPRN(SPRG6, 0x56);
+ LOAD_SPRN(SPRG7, 0x57);
+
+ LOAD_SPRN(IABR, 0x58);
+ LOAD_SPRN(DABR, 0x59);
+ LOAD_SPRN(TBWL, 0x5a); /* these two have separate R/W regs */
+ LOAD_SPRN(TBWU, 0x5b);
+
+ blr
+_ASM_NOKPROBE_SYMBOL(restore_regs)
+SYM_FUNC_END(restore_regs)
+
+
+
+/* cache flushing code. copied from arch/ppc/boot/util.S */
+#define NUM_CACHE_LINES (128*8)
+
+/*
+ * Flush data cache
+ * Do this by just reading lots of stuff into the cache.
+ */
+SYM_FUNC_START_LOCAL(flush_data_cache)
+ lis r3,CONFIG_KERNEL_START@h
+ ori r3,r3,CONFIG_KERNEL_START@l
+ li r4,NUM_CACHE_LINES
+ mtctr r4
+1:
+ lwz r4,0(r3)
+ addi r3,r3,L1_CACHE_BYTES /* Next line, please */
+ bdnz 1b
+ blr
+SYM_FUNC_END(flush_data_cache)