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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 /drivers/mtd/spi-nor/swp.c
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 'drivers/mtd/spi-nor/swp.c')
-rw-r--r--drivers/mtd/spi-nor/swp.c427
1 files changed, 427 insertions, 0 deletions
diff --git a/drivers/mtd/spi-nor/swp.c b/drivers/mtd/spi-nor/swp.c
new file mode 100644
index 000000000..1f178313b
--- /dev/null
+++ b/drivers/mtd/spi-nor/swp.c
@@ -0,0 +1,427 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPI NOR Software Write Protection logic.
+ *
+ * Copyright (C) 2005, Intec Automation Inc.
+ * Copyright (C) 2014, Freescale Semiconductor, Inc.
+ */
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/spi-nor.h>
+
+#include "core.h"
+
+static u8 spi_nor_get_sr_bp_mask(struct spi_nor *nor)
+{
+ u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
+
+ if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6)
+ return mask | SR_BP3_BIT6;
+
+ if (nor->flags & SNOR_F_HAS_4BIT_BP)
+ return mask | SR_BP3;
+
+ return mask;
+}
+
+static u8 spi_nor_get_sr_tb_mask(struct spi_nor *nor)
+{
+ if (nor->flags & SNOR_F_HAS_SR_TB_BIT6)
+ return SR_TB_BIT6;
+ else
+ return SR_TB_BIT5;
+}
+
+static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)
+{
+ unsigned int bp_slots, bp_slots_needed;
+ u8 mask = spi_nor_get_sr_bp_mask(nor);
+
+ /* Reserved one for "protect none" and one for "protect all". */
+ bp_slots = (1 << hweight8(mask)) - 2;
+ bp_slots_needed = ilog2(nor->info->n_sectors);
+
+ if (bp_slots_needed > bp_slots)
+ return nor->info->sector_size <<
+ (bp_slots_needed - bp_slots);
+ else
+ return nor->info->sector_size;
+}
+
+static void spi_nor_get_locked_range_sr(struct spi_nor *nor, u8 sr, loff_t *ofs,
+ uint64_t *len)
+{
+ struct mtd_info *mtd = &nor->mtd;
+ u64 min_prot_len;
+ u8 mask = spi_nor_get_sr_bp_mask(nor);
+ u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
+ u8 bp, val = sr & mask;
+
+ if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3_BIT6)
+ val = (val & ~SR_BP3_BIT6) | SR_BP3;
+
+ bp = val >> SR_BP_SHIFT;
+
+ if (!bp) {
+ /* No protection */
+ *ofs = 0;
+ *len = 0;
+ return;
+ }
+
+ min_prot_len = spi_nor_get_min_prot_length_sr(nor);
+ *len = min_prot_len << (bp - 1);
+
+ if (*len > mtd->size)
+ *len = mtd->size;
+
+ if (nor->flags & SNOR_F_HAS_SR_TB && sr & tb_mask)
+ *ofs = 0;
+ else
+ *ofs = mtd->size - *len;
+}
+
+/*
+ * Return true if the entire region is locked (if @locked is true) or unlocked
+ * (if @locked is false); false otherwise.
+ */
+static bool spi_nor_check_lock_status_sr(struct spi_nor *nor, loff_t ofs,
+ uint64_t len, u8 sr, bool locked)
+{
+ loff_t lock_offs, lock_offs_max, offs_max;
+ uint64_t lock_len;
+
+ if (!len)
+ return true;
+
+ spi_nor_get_locked_range_sr(nor, sr, &lock_offs, &lock_len);
+
+ lock_offs_max = lock_offs + lock_len;
+ offs_max = ofs + len;
+
+ if (locked)
+ /* Requested range is a sub-range of locked range */
+ return (offs_max <= lock_offs_max) && (ofs >= lock_offs);
+ else
+ /* Requested range does not overlap with locked range */
+ return (ofs >= lock_offs_max) || (offs_max <= lock_offs);
+}
+
+static bool spi_nor_is_locked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len,
+ u8 sr)
+{
+ return spi_nor_check_lock_status_sr(nor, ofs, len, sr, true);
+}
+
+static bool spi_nor_is_unlocked_sr(struct spi_nor *nor, loff_t ofs,
+ uint64_t len, u8 sr)
+{
+ return spi_nor_check_lock_status_sr(nor, ofs, len, sr, false);
+}
+
+/*
+ * Lock a region of the flash. Compatible with ST Micro and similar flash.
+ * Supports the block protection bits BP{0,1,2}/BP{0,1,2,3} in the status
+ * register
+ * (SR). Does not support these features found in newer SR bitfields:
+ * - SEC: sector/block protect - only handle SEC=0 (block protect)
+ * - CMP: complement protect - only support CMP=0 (range is not complemented)
+ *
+ * Support for the following is provided conditionally for some flash:
+ * - TB: top/bottom protect
+ *
+ * Sample table portion for 8MB flash (Winbond w25q64fw):
+ *
+ * SEC | TB | BP2 | BP1 | BP0 | Prot Length | Protected Portion
+ * --------------------------------------------------------------------------
+ * X | X | 0 | 0 | 0 | NONE | NONE
+ * 0 | 0 | 0 | 0 | 1 | 128 KB | Upper 1/64
+ * 0 | 0 | 0 | 1 | 0 | 256 KB | Upper 1/32
+ * 0 | 0 | 0 | 1 | 1 | 512 KB | Upper 1/16
+ * 0 | 0 | 1 | 0 | 0 | 1 MB | Upper 1/8
+ * 0 | 0 | 1 | 0 | 1 | 2 MB | Upper 1/4
+ * 0 | 0 | 1 | 1 | 0 | 4 MB | Upper 1/2
+ * X | X | 1 | 1 | 1 | 8 MB | ALL
+ * ------|-------|-------|-------|-------|---------------|-------------------
+ * 0 | 1 | 0 | 0 | 1 | 128 KB | Lower 1/64
+ * 0 | 1 | 0 | 1 | 0 | 256 KB | Lower 1/32
+ * 0 | 1 | 0 | 1 | 1 | 512 KB | Lower 1/16
+ * 0 | 1 | 1 | 0 | 0 | 1 MB | Lower 1/8
+ * 0 | 1 | 1 | 0 | 1 | 2 MB | Lower 1/4
+ * 0 | 1 | 1 | 1 | 0 | 4 MB | Lower 1/2
+ *
+ * Returns negative on errors, 0 on success.
+ */
+static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
+{
+ struct mtd_info *mtd = &nor->mtd;
+ u64 min_prot_len;
+ int ret, status_old, status_new;
+ u8 mask = spi_nor_get_sr_bp_mask(nor);
+ u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
+ u8 pow, val;
+ loff_t lock_len;
+ bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
+ bool use_top;
+
+ ret = spi_nor_read_sr(nor, nor->bouncebuf);
+ if (ret)
+ return ret;
+
+ status_old = nor->bouncebuf[0];
+
+ /* If nothing in our range is unlocked, we don't need to do anything */
+ if (spi_nor_is_locked_sr(nor, ofs, len, status_old))
+ return 0;
+
+ /* If anything below us is unlocked, we can't use 'bottom' protection */
+ if (!spi_nor_is_locked_sr(nor, 0, ofs, status_old))
+ can_be_bottom = false;
+
+ /* If anything above us is unlocked, we can't use 'top' protection */
+ if (!spi_nor_is_locked_sr(nor, ofs + len, mtd->size - (ofs + len),
+ status_old))
+ can_be_top = false;
+
+ if (!can_be_bottom && !can_be_top)
+ return -EINVAL;
+
+ /* Prefer top, if both are valid */
+ use_top = can_be_top;
+
+ /* lock_len: length of region that should end up locked */
+ if (use_top)
+ lock_len = mtd->size - ofs;
+ else
+ lock_len = ofs + len;
+
+ if (lock_len == mtd->size) {
+ val = mask;
+ } else {
+ min_prot_len = spi_nor_get_min_prot_length_sr(nor);
+ pow = ilog2(lock_len) - ilog2(min_prot_len) + 1;
+ val = pow << SR_BP_SHIFT;
+
+ if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)
+ val = (val & ~SR_BP3) | SR_BP3_BIT6;
+
+ if (val & ~mask)
+ return -EINVAL;
+
+ /* Don't "lock" with no region! */
+ if (!(val & mask))
+ return -EINVAL;
+ }
+
+ status_new = (status_old & ~mask & ~tb_mask) | val;
+
+ /* Disallow further writes if WP pin is asserted */
+ status_new |= SR_SRWD;
+
+ if (!use_top)
+ status_new |= tb_mask;
+
+ /* Don't bother if they're the same */
+ if (status_new == status_old)
+ return 0;
+
+ /* Only modify protection if it will not unlock other areas */
+ if ((status_new & mask) < (status_old & mask))
+ return -EINVAL;
+
+ return spi_nor_write_sr_and_check(nor, status_new);
+}
+
+/*
+ * Unlock a region of the flash. See spi_nor_sr_lock() for more info
+ *
+ * Returns negative on errors, 0 on success.
+ */
+static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
+{
+ struct mtd_info *mtd = &nor->mtd;
+ u64 min_prot_len;
+ int ret, status_old, status_new;
+ u8 mask = spi_nor_get_sr_bp_mask(nor);
+ u8 tb_mask = spi_nor_get_sr_tb_mask(nor);
+ u8 pow, val;
+ loff_t lock_len;
+ bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB;
+ bool use_top;
+
+ ret = spi_nor_read_sr(nor, nor->bouncebuf);
+ if (ret)
+ return ret;
+
+ status_old = nor->bouncebuf[0];
+
+ /* If nothing in our range is locked, we don't need to do anything */
+ if (spi_nor_is_unlocked_sr(nor, ofs, len, status_old))
+ return 0;
+
+ /* If anything below us is locked, we can't use 'top' protection */
+ if (!spi_nor_is_unlocked_sr(nor, 0, ofs, status_old))
+ can_be_top = false;
+
+ /* If anything above us is locked, we can't use 'bottom' protection */
+ if (!spi_nor_is_unlocked_sr(nor, ofs + len, mtd->size - (ofs + len),
+ status_old))
+ can_be_bottom = false;
+
+ if (!can_be_bottom && !can_be_top)
+ return -EINVAL;
+
+ /* Prefer top, if both are valid */
+ use_top = can_be_top;
+
+ /* lock_len: length of region that should remain locked */
+ if (use_top)
+ lock_len = mtd->size - (ofs + len);
+ else
+ lock_len = ofs;
+
+ if (lock_len == 0) {
+ val = 0; /* fully unlocked */
+ } else {
+ min_prot_len = spi_nor_get_min_prot_length_sr(nor);
+ pow = ilog2(lock_len) - ilog2(min_prot_len) + 1;
+ val = pow << SR_BP_SHIFT;
+
+ if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3)
+ val = (val & ~SR_BP3) | SR_BP3_BIT6;
+
+ /* Some power-of-two sizes are not supported */
+ if (val & ~mask)
+ return -EINVAL;
+ }
+
+ status_new = (status_old & ~mask & ~tb_mask) | val;
+
+ /* Don't protect status register if we're fully unlocked */
+ if (lock_len == 0)
+ status_new &= ~SR_SRWD;
+
+ if (!use_top)
+ status_new |= tb_mask;
+
+ /* Don't bother if they're the same */
+ if (status_new == status_old)
+ return 0;
+
+ /* Only modify protection if it will not lock other areas */
+ if ((status_new & mask) > (status_old & mask))
+ return -EINVAL;
+
+ return spi_nor_write_sr_and_check(nor, status_new);
+}
+
+/*
+ * Check if a region of the flash is (completely) locked. See spi_nor_sr_lock()
+ * for more info.
+ *
+ * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
+ * negative on errors.
+ */
+static int spi_nor_sr_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)
+{
+ int ret;
+
+ ret = spi_nor_read_sr(nor, nor->bouncebuf);
+ if (ret)
+ return ret;
+
+ return spi_nor_is_locked_sr(nor, ofs, len, nor->bouncebuf[0]);
+}
+
+static const struct spi_nor_locking_ops spi_nor_sr_locking_ops = {
+ .lock = spi_nor_sr_lock,
+ .unlock = spi_nor_sr_unlock,
+ .is_locked = spi_nor_sr_is_locked,
+};
+
+void spi_nor_init_default_locking_ops(struct spi_nor *nor)
+{
+ nor->params->locking_ops = &spi_nor_sr_locking_ops;
+}
+
+static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ int ret;
+
+ ret = spi_nor_lock_and_prep(nor);
+ if (ret)
+ return ret;
+
+ ret = nor->params->locking_ops->lock(nor, ofs, len);
+
+ spi_nor_unlock_and_unprep(nor);
+ return ret;
+}
+
+static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ int ret;
+
+ ret = spi_nor_lock_and_prep(nor);
+ if (ret)
+ return ret;
+
+ ret = nor->params->locking_ops->unlock(nor, ofs, len);
+
+ spi_nor_unlock_and_unprep(nor);
+ return ret;
+}
+
+static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ int ret;
+
+ ret = spi_nor_lock_and_prep(nor);
+ if (ret)
+ return ret;
+
+ ret = nor->params->locking_ops->is_locked(nor, ofs, len);
+
+ spi_nor_unlock_and_unprep(nor);
+ return ret;
+}
+
+/**
+ * spi_nor_try_unlock_all() - Tries to unlock the entire flash memory array.
+ * @nor: pointer to a 'struct spi_nor'.
+ *
+ * Some SPI NOR flashes are write protected by default after a power-on reset
+ * cycle, in order to avoid inadvertent writes during power-up. Backward
+ * compatibility imposes to unlock the entire flash memory array at power-up
+ * by default.
+ *
+ * Unprotecting the entire flash array will fail for boards which are hardware
+ * write-protected. Thus any errors are ignored.
+ */
+void spi_nor_try_unlock_all(struct spi_nor *nor)
+{
+ int ret;
+
+ if (!(nor->flags & SNOR_F_HAS_LOCK))
+ return;
+
+ dev_dbg(nor->dev, "Unprotecting entire flash array\n");
+
+ ret = spi_nor_unlock(&nor->mtd, 0, nor->params->size);
+ if (ret)
+ dev_dbg(nor->dev, "Failed to unlock the entire flash memory array\n");
+}
+
+void spi_nor_set_mtd_locking_ops(struct spi_nor *nor)
+{
+ struct mtd_info *mtd = &nor->mtd;
+
+ if (!nor->params->locking_ops)
+ return;
+
+ mtd->_lock = spi_nor_lock;
+ mtd->_unlock = spi_nor_unlock;
+ mtd->_is_locked = spi_nor_is_locked;
+}