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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/mtd/nand/ecc-sw-hamming.c | |
download | linux-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 'drivers/mtd/nand/ecc-sw-hamming.c')
-rw-r--r-- | drivers/mtd/nand/ecc-sw-hamming.c | 660 |
1 files changed, 660 insertions, 0 deletions
diff --git a/drivers/mtd/nand/ecc-sw-hamming.c b/drivers/mtd/nand/ecc-sw-hamming.c new file mode 100644 index 000000000..254db2e7f --- /dev/null +++ b/drivers/mtd/nand/ecc-sw-hamming.c @@ -0,0 +1,660 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * This file contains an ECC algorithm that detects and corrects 1 bit + * errors in a 256 byte block of data. + * + * Copyright © 2008 Koninklijke Philips Electronics NV. + * Author: Frans Meulenbroeks + * + * Completely replaces the previous ECC implementation which was written by: + * Steven J. Hill (sjhill@realitydiluted.com) + * Thomas Gleixner (tglx@linutronix.de) + * + * Information on how this algorithm works and how it was developed + * can be found in Documentation/driver-api/mtd/nand_ecc.rst + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mtd/nand.h> +#include <linux/mtd/nand-ecc-sw-hamming.h> +#include <linux/slab.h> +#include <asm/byteorder.h> + +/* + * invparity is a 256 byte table that contains the odd parity + * for each byte. So if the number of bits in a byte is even, + * the array element is 1, and when the number of bits is odd + * the array eleemnt is 0. + */ +static const char invparity[256] = { + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1 +}; + +/* + * bitsperbyte contains the number of bits per byte + * this is only used for testing and repairing parity + * (a precalculated value slightly improves performance) + */ +static const char bitsperbyte[256] = { + 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, + 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, + 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, + 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, + 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, + 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, + 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, + 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, + 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, + 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, + 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, + 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, + 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, + 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, + 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, + 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, +}; + +/* + * addressbits is a lookup table to filter out the bits from the xor-ed + * ECC data that identify the faulty location. + * this is only used for repairing parity + * see the comments in nand_ecc_sw_hamming_correct for more details + */ +static const char addressbits[256] = { + 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, + 0x02, 0x02, 0x03, 0x03, 0x02, 0x02, 0x03, 0x03, + 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, + 0x02, 0x02, 0x03, 0x03, 0x02, 0x02, 0x03, 0x03, + 0x04, 0x04, 0x05, 0x05, 0x04, 0x04, 0x05, 0x05, + 0x06, 0x06, 0x07, 0x07, 0x06, 0x06, 0x07, 0x07, + 0x04, 0x04, 0x05, 0x05, 0x04, 0x04, 0x05, 0x05, + 0x06, 0x06, 0x07, 0x07, 0x06, 0x06, 0x07, 0x07, + 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, + 0x02, 0x02, 0x03, 0x03, 0x02, 0x02, 0x03, 0x03, + 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x01, 0x01, + 0x02, 0x02, 0x03, 0x03, 0x02, 0x02, 0x03, 0x03, + 0x04, 0x04, 0x05, 0x05, 0x04, 0x04, 0x05, 0x05, + 0x06, 0x06, 0x07, 0x07, 0x06, 0x06, 0x07, 0x07, + 0x04, 0x04, 0x05, 0x05, 0x04, 0x04, 0x05, 0x05, + 0x06, 0x06, 0x07, 0x07, 0x06, 0x06, 0x07, 0x07, + 0x08, 0x08, 0x09, 0x09, 0x08, 0x08, 0x09, 0x09, + 0x0a, 0x0a, 0x0b, 0x0b, 0x0a, 0x0a, 0x0b, 0x0b, + 0x08, 0x08, 0x09, 0x09, 0x08, 0x08, 0x09, 0x09, + 0x0a, 0x0a, 0x0b, 0x0b, 0x0a, 0x0a, 0x0b, 0x0b, + 0x0c, 0x0c, 0x0d, 0x0d, 0x0c, 0x0c, 0x0d, 0x0d, + 0x0e, 0x0e, 0x0f, 0x0f, 0x0e, 0x0e, 0x0f, 0x0f, + 0x0c, 0x0c, 0x0d, 0x0d, 0x0c, 0x0c, 0x0d, 0x0d, + 0x0e, 0x0e, 0x0f, 0x0f, 0x0e, 0x0e, 0x0f, 0x0f, + 0x08, 0x08, 0x09, 0x09, 0x08, 0x08, 0x09, 0x09, + 0x0a, 0x0a, 0x0b, 0x0b, 0x0a, 0x0a, 0x0b, 0x0b, + 0x08, 0x08, 0x09, 0x09, 0x08, 0x08, 0x09, 0x09, + 0x0a, 0x0a, 0x0b, 0x0b, 0x0a, 0x0a, 0x0b, 0x0b, + 0x0c, 0x0c, 0x0d, 0x0d, 0x0c, 0x0c, 0x0d, 0x0d, + 0x0e, 0x0e, 0x0f, 0x0f, 0x0e, 0x0e, 0x0f, 0x0f, + 0x0c, 0x0c, 0x0d, 0x0d, 0x0c, 0x0c, 0x0d, 0x0d, + 0x0e, 0x0e, 0x0f, 0x0f, 0x0e, 0x0e, 0x0f, 0x0f +}; + +int ecc_sw_hamming_calculate(const unsigned char *buf, unsigned int step_size, + unsigned char *code, bool sm_order) +{ + const u32 *bp = (uint32_t *)buf; + const u32 eccsize_mult = (step_size == 256) ? 1 : 2; + /* current value in buffer */ + u32 cur; + /* rp0..rp17 are the various accumulated parities (per byte) */ + u32 rp0, rp1, rp2, rp3, rp4, rp5, rp6, rp7, rp8, rp9, rp10, rp11, rp12, + rp13, rp14, rp15, rp16, rp17; + /* Cumulative parity for all data */ + u32 par; + /* Cumulative parity at the end of the loop (rp12, rp14, rp16) */ + u32 tmppar; + int i; + + par = 0; + rp4 = 0; + rp6 = 0; + rp8 = 0; + rp10 = 0; + rp12 = 0; + rp14 = 0; + rp16 = 0; + rp17 = 0; + + /* + * The loop is unrolled a number of times; + * This avoids if statements to decide on which rp value to update + * Also we process the data by longwords. + * Note: passing unaligned data might give a performance penalty. + * It is assumed that the buffers are aligned. + * tmppar is the cumulative sum of this iteration. + * needed for calculating rp12, rp14, rp16 and par + * also used as a performance improvement for rp6, rp8 and rp10 + */ + for (i = 0; i < eccsize_mult << 2; i++) { + cur = *bp++; + tmppar = cur; + rp4 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp6 ^= tmppar; + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp8 ^= tmppar; + + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + rp6 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp6 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp10 ^= tmppar; + + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + rp6 ^= cur; + rp8 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp6 ^= cur; + rp8 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + rp8 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp8 ^= cur; + + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + rp6 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp6 ^= cur; + cur = *bp++; + tmppar ^= cur; + rp4 ^= cur; + cur = *bp++; + tmppar ^= cur; + + par ^= tmppar; + if ((i & 0x1) == 0) + rp12 ^= tmppar; + if ((i & 0x2) == 0) + rp14 ^= tmppar; + if (eccsize_mult == 2 && (i & 0x4) == 0) + rp16 ^= tmppar; + } + + /* + * handle the fact that we use longword operations + * we'll bring rp4..rp14..rp16 back to single byte entities by + * shifting and xoring first fold the upper and lower 16 bits, + * then the upper and lower 8 bits. + */ + rp4 ^= (rp4 >> 16); + rp4 ^= (rp4 >> 8); + rp4 &= 0xff; + rp6 ^= (rp6 >> 16); + rp6 ^= (rp6 >> 8); + rp6 &= 0xff; + rp8 ^= (rp8 >> 16); + rp8 ^= (rp8 >> 8); + rp8 &= 0xff; + rp10 ^= (rp10 >> 16); + rp10 ^= (rp10 >> 8); + rp10 &= 0xff; + rp12 ^= (rp12 >> 16); + rp12 ^= (rp12 >> 8); + rp12 &= 0xff; + rp14 ^= (rp14 >> 16); + rp14 ^= (rp14 >> 8); + rp14 &= 0xff; + if (eccsize_mult == 2) { + rp16 ^= (rp16 >> 16); + rp16 ^= (rp16 >> 8); + rp16 &= 0xff; + } + + /* + * we also need to calculate the row parity for rp0..rp3 + * This is present in par, because par is now + * rp3 rp3 rp2 rp2 in little endian and + * rp2 rp2 rp3 rp3 in big endian + * as well as + * rp1 rp0 rp1 rp0 in little endian and + * rp0 rp1 rp0 rp1 in big endian + * First calculate rp2 and rp3 + */ +#ifdef __BIG_ENDIAN + rp2 = (par >> 16); + rp2 ^= (rp2 >> 8); + rp2 &= 0xff; + rp3 = par & 0xffff; + rp3 ^= (rp3 >> 8); + rp3 &= 0xff; +#else + rp3 = (par >> 16); + rp3 ^= (rp3 >> 8); + rp3 &= 0xff; + rp2 = par & 0xffff; + rp2 ^= (rp2 >> 8); + rp2 &= 0xff; +#endif + + /* reduce par to 16 bits then calculate rp1 and rp0 */ + par ^= (par >> 16); +#ifdef __BIG_ENDIAN + rp0 = (par >> 8) & 0xff; + rp1 = (par & 0xff); +#else + rp1 = (par >> 8) & 0xff; + rp0 = (par & 0xff); +#endif + + /* finally reduce par to 8 bits */ + par ^= (par >> 8); + par &= 0xff; + + /* + * and calculate rp5..rp15..rp17 + * note that par = rp4 ^ rp5 and due to the commutative property + * of the ^ operator we can say: + * rp5 = (par ^ rp4); + * The & 0xff seems superfluous, but benchmarking learned that + * leaving it out gives slightly worse results. No idea why, probably + * it has to do with the way the pipeline in pentium is organized. + */ + rp5 = (par ^ rp4) & 0xff; + rp7 = (par ^ rp6) & 0xff; + rp9 = (par ^ rp8) & 0xff; + rp11 = (par ^ rp10) & 0xff; + rp13 = (par ^ rp12) & 0xff; + rp15 = (par ^ rp14) & 0xff; + if (eccsize_mult == 2) + rp17 = (par ^ rp16) & 0xff; + + /* + * Finally calculate the ECC bits. + * Again here it might seem that there are performance optimisations + * possible, but benchmarks showed that on the system this is developed + * the code below is the fastest + */ + if (sm_order) { + code[0] = (invparity[rp7] << 7) | (invparity[rp6] << 6) | + (invparity[rp5] << 5) | (invparity[rp4] << 4) | + (invparity[rp3] << 3) | (invparity[rp2] << 2) | + (invparity[rp1] << 1) | (invparity[rp0]); + code[1] = (invparity[rp15] << 7) | (invparity[rp14] << 6) | + (invparity[rp13] << 5) | (invparity[rp12] << 4) | + (invparity[rp11] << 3) | (invparity[rp10] << 2) | + (invparity[rp9] << 1) | (invparity[rp8]); + } else { + code[1] = (invparity[rp7] << 7) | (invparity[rp6] << 6) | + (invparity[rp5] << 5) | (invparity[rp4] << 4) | + (invparity[rp3] << 3) | (invparity[rp2] << 2) | + (invparity[rp1] << 1) | (invparity[rp0]); + code[0] = (invparity[rp15] << 7) | (invparity[rp14] << 6) | + (invparity[rp13] << 5) | (invparity[rp12] << 4) | + (invparity[rp11] << 3) | (invparity[rp10] << 2) | + (invparity[rp9] << 1) | (invparity[rp8]); + } + + if (eccsize_mult == 1) + code[2] = + (invparity[par & 0xf0] << 7) | + (invparity[par & 0x0f] << 6) | + (invparity[par & 0xcc] << 5) | + (invparity[par & 0x33] << 4) | + (invparity[par & 0xaa] << 3) | + (invparity[par & 0x55] << 2) | + 3; + else + code[2] = + (invparity[par & 0xf0] << 7) | + (invparity[par & 0x0f] << 6) | + (invparity[par & 0xcc] << 5) | + (invparity[par & 0x33] << 4) | + (invparity[par & 0xaa] << 3) | + (invparity[par & 0x55] << 2) | + (invparity[rp17] << 1) | + (invparity[rp16] << 0); + + return 0; +} +EXPORT_SYMBOL(ecc_sw_hamming_calculate); + +/** + * nand_ecc_sw_hamming_calculate - Calculate 3-byte ECC for 256/512-byte block + * @nand: NAND device + * @buf: Input buffer with raw data + * @code: Output buffer with ECC + */ +int nand_ecc_sw_hamming_calculate(struct nand_device *nand, + const unsigned char *buf, unsigned char *code) +{ + struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv; + unsigned int step_size = nand->ecc.ctx.conf.step_size; + bool sm_order = engine_conf ? engine_conf->sm_order : false; + + return ecc_sw_hamming_calculate(buf, step_size, code, sm_order); +} +EXPORT_SYMBOL(nand_ecc_sw_hamming_calculate); + +int ecc_sw_hamming_correct(unsigned char *buf, unsigned char *read_ecc, + unsigned char *calc_ecc, unsigned int step_size, + bool sm_order) +{ + const u32 eccsize_mult = step_size >> 8; + unsigned char b0, b1, b2, bit_addr; + unsigned int byte_addr; + + /* + * b0 to b2 indicate which bit is faulty (if any) + * we might need the xor result more than once, + * so keep them in a local var + */ + if (sm_order) { + b0 = read_ecc[0] ^ calc_ecc[0]; + b1 = read_ecc[1] ^ calc_ecc[1]; + } else { + b0 = read_ecc[1] ^ calc_ecc[1]; + b1 = read_ecc[0] ^ calc_ecc[0]; + } + + b2 = read_ecc[2] ^ calc_ecc[2]; + + /* check if there are any bitfaults */ + + /* repeated if statements are slightly more efficient than switch ... */ + /* ordered in order of likelihood */ + + if ((b0 | b1 | b2) == 0) + return 0; /* no error */ + + if ((((b0 ^ (b0 >> 1)) & 0x55) == 0x55) && + (((b1 ^ (b1 >> 1)) & 0x55) == 0x55) && + ((eccsize_mult == 1 && ((b2 ^ (b2 >> 1)) & 0x54) == 0x54) || + (eccsize_mult == 2 && ((b2 ^ (b2 >> 1)) & 0x55) == 0x55))) { + /* single bit error */ + /* + * rp17/rp15/13/11/9/7/5/3/1 indicate which byte is the faulty + * byte, cp 5/3/1 indicate the faulty bit. + * A lookup table (called addressbits) is used to filter + * the bits from the byte they are in. + * A marginal optimisation is possible by having three + * different lookup tables. + * One as we have now (for b0), one for b2 + * (that would avoid the >> 1), and one for b1 (with all values + * << 4). However it was felt that introducing two more tables + * hardly justify the gain. + * + * The b2 shift is there to get rid of the lowest two bits. + * We could also do addressbits[b2] >> 1 but for the + * performance it does not make any difference + */ + if (eccsize_mult == 1) + byte_addr = (addressbits[b1] << 4) + addressbits[b0]; + else + byte_addr = (addressbits[b2 & 0x3] << 8) + + (addressbits[b1] << 4) + addressbits[b0]; + bit_addr = addressbits[b2 >> 2]; + /* flip the bit */ + buf[byte_addr] ^= (1 << bit_addr); + return 1; + + } + /* count nr of bits; use table lookup, faster than calculating it */ + if ((bitsperbyte[b0] + bitsperbyte[b1] + bitsperbyte[b2]) == 1) + return 1; /* error in ECC data; no action needed */ + + pr_err("%s: uncorrectable ECC error\n", __func__); + return -EBADMSG; +} +EXPORT_SYMBOL(ecc_sw_hamming_correct); + +/** + * nand_ecc_sw_hamming_correct - Detect and correct bit error(s) + * @nand: NAND device + * @buf: Raw data read from the chip + * @read_ecc: ECC bytes read from the chip + * @calc_ecc: ECC calculated from the raw data + * + * Detect and correct up to 1 bit error per 256/512-byte block. + */ +int nand_ecc_sw_hamming_correct(struct nand_device *nand, unsigned char *buf, + unsigned char *read_ecc, + unsigned char *calc_ecc) +{ + struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv; + unsigned int step_size = nand->ecc.ctx.conf.step_size; + bool sm_order = engine_conf ? engine_conf->sm_order : false; + + return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc, step_size, + sm_order); +} +EXPORT_SYMBOL(nand_ecc_sw_hamming_correct); + +int nand_ecc_sw_hamming_init_ctx(struct nand_device *nand) +{ + struct nand_ecc_props *conf = &nand->ecc.ctx.conf; + struct nand_ecc_sw_hamming_conf *engine_conf; + struct mtd_info *mtd = nanddev_to_mtd(nand); + int ret; + + if (!mtd->ooblayout) { + switch (mtd->oobsize) { + case 8: + case 16: + mtd_set_ooblayout(mtd, nand_get_small_page_ooblayout()); + break; + case 64: + case 128: + mtd_set_ooblayout(mtd, + nand_get_large_page_hamming_ooblayout()); + break; + default: + return -ENOTSUPP; + } + } + + conf->engine_type = NAND_ECC_ENGINE_TYPE_SOFT; + conf->algo = NAND_ECC_ALGO_HAMMING; + conf->step_size = nand->ecc.user_conf.step_size; + conf->strength = 1; + + /* Use the strongest configuration by default */ + if (conf->step_size != 256 && conf->step_size != 512) + conf->step_size = 256; + + engine_conf = kzalloc(sizeof(*engine_conf), GFP_KERNEL); + if (!engine_conf) + return -ENOMEM; + + ret = nand_ecc_init_req_tweaking(&engine_conf->req_ctx, nand); + if (ret) + goto free_engine_conf; + + engine_conf->code_size = 3; + engine_conf->calc_buf = kzalloc(mtd->oobsize, GFP_KERNEL); + engine_conf->code_buf = kzalloc(mtd->oobsize, GFP_KERNEL); + if (!engine_conf->calc_buf || !engine_conf->code_buf) { + ret = -ENOMEM; + goto free_bufs; + } + + nand->ecc.ctx.priv = engine_conf; + nand->ecc.ctx.nsteps = mtd->writesize / conf->step_size; + nand->ecc.ctx.total = nand->ecc.ctx.nsteps * engine_conf->code_size; + + return 0; + +free_bufs: + nand_ecc_cleanup_req_tweaking(&engine_conf->req_ctx); + kfree(engine_conf->calc_buf); + kfree(engine_conf->code_buf); +free_engine_conf: + kfree(engine_conf); + + return ret; +} +EXPORT_SYMBOL(nand_ecc_sw_hamming_init_ctx); + +void nand_ecc_sw_hamming_cleanup_ctx(struct nand_device *nand) +{ + struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv; + + if (engine_conf) { + nand_ecc_cleanup_req_tweaking(&engine_conf->req_ctx); + kfree(engine_conf->calc_buf); + kfree(engine_conf->code_buf); + kfree(engine_conf); + } +} +EXPORT_SYMBOL(nand_ecc_sw_hamming_cleanup_ctx); + +static int nand_ecc_sw_hamming_prepare_io_req(struct nand_device *nand, + struct nand_page_io_req *req) +{ + struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv; + struct mtd_info *mtd = nanddev_to_mtd(nand); + int eccsize = nand->ecc.ctx.conf.step_size; + int eccbytes = engine_conf->code_size; + int eccsteps = nand->ecc.ctx.nsteps; + int total = nand->ecc.ctx.total; + u8 *ecccalc = engine_conf->calc_buf; + const u8 *data; + int i; + + /* Nothing to do for a raw operation */ + if (req->mode == MTD_OPS_RAW) + return 0; + + /* This engine does not provide BBM/free OOB bytes protection */ + if (!req->datalen) + return 0; + + nand_ecc_tweak_req(&engine_conf->req_ctx, req); + + /* No more preparation for page read */ + if (req->type == NAND_PAGE_READ) + return 0; + + /* Preparation for page write: derive the ECC bytes and place them */ + for (i = 0, data = req->databuf.out; + eccsteps; + eccsteps--, i += eccbytes, data += eccsize) + nand_ecc_sw_hamming_calculate(nand, data, &ecccalc[i]); + + return mtd_ooblayout_set_eccbytes(mtd, ecccalc, (void *)req->oobbuf.out, + 0, total); +} + +static int nand_ecc_sw_hamming_finish_io_req(struct nand_device *nand, + struct nand_page_io_req *req) +{ + struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv; + struct mtd_info *mtd = nanddev_to_mtd(nand); + int eccsize = nand->ecc.ctx.conf.step_size; + int total = nand->ecc.ctx.total; + int eccbytes = engine_conf->code_size; + int eccsteps = nand->ecc.ctx.nsteps; + u8 *ecccalc = engine_conf->calc_buf; + u8 *ecccode = engine_conf->code_buf; + unsigned int max_bitflips = 0; + u8 *data = req->databuf.in; + int i, ret; + + /* Nothing to do for a raw operation */ + if (req->mode == MTD_OPS_RAW) + return 0; + + /* This engine does not provide BBM/free OOB bytes protection */ + if (!req->datalen) + return 0; + + /* No more preparation for page write */ + if (req->type == NAND_PAGE_WRITE) { + nand_ecc_restore_req(&engine_conf->req_ctx, req); + return 0; + } + + /* Finish a page read: retrieve the (raw) ECC bytes*/ + ret = mtd_ooblayout_get_eccbytes(mtd, ecccode, req->oobbuf.in, 0, + total); + if (ret) + return ret; + + /* Calculate the ECC bytes */ + for (i = 0; eccsteps; eccsteps--, i += eccbytes, data += eccsize) + nand_ecc_sw_hamming_calculate(nand, data, &ecccalc[i]); + + /* Finish a page read: compare and correct */ + for (eccsteps = nand->ecc.ctx.nsteps, i = 0, data = req->databuf.in; + eccsteps; + eccsteps--, i += eccbytes, data += eccsize) { + int stat = nand_ecc_sw_hamming_correct(nand, data, + &ecccode[i], + &ecccalc[i]); + if (stat < 0) { + mtd->ecc_stats.failed++; + } else { + mtd->ecc_stats.corrected += stat; + max_bitflips = max_t(unsigned int, max_bitflips, stat); + } + } + + nand_ecc_restore_req(&engine_conf->req_ctx, req); + + return max_bitflips; +} + +static struct nand_ecc_engine_ops nand_ecc_sw_hamming_engine_ops = { + .init_ctx = nand_ecc_sw_hamming_init_ctx, + .cleanup_ctx = nand_ecc_sw_hamming_cleanup_ctx, + .prepare_io_req = nand_ecc_sw_hamming_prepare_io_req, + .finish_io_req = nand_ecc_sw_hamming_finish_io_req, +}; + +static struct nand_ecc_engine nand_ecc_sw_hamming_engine = { + .ops = &nand_ecc_sw_hamming_engine_ops, +}; + +struct nand_ecc_engine *nand_ecc_sw_hamming_get_engine(void) +{ + return &nand_ecc_sw_hamming_engine; +} +EXPORT_SYMBOL(nand_ecc_sw_hamming_get_engine); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Frans Meulenbroeks <fransmeulenbroeks@gmail.com>"); +MODULE_DESCRIPTION("NAND software Hamming ECC support"); |