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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/char/nvram.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/char/nvram.c')
-rw-r--r--drivers/char/nvram.c545
1 files changed, 545 insertions, 0 deletions
diff --git a/drivers/char/nvram.c b/drivers/char/nvram.c
new file mode 100644
index 000000000..e9f694b36
--- /dev/null
+++ b/drivers/char/nvram.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * CMOS/NV-RAM driver for Linux
+ *
+ * Copyright (C) 1997 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
+ * idea by and with help from Richard Jelinek <rj@suse.de>
+ * Portions copyright (c) 2001,2002 Sun Microsystems (thockin@sun.com)
+ *
+ * This driver allows you to access the contents of the non-volatile memory in
+ * the mc146818rtc.h real-time clock. This chip is built into all PCs and into
+ * many Atari machines. In the former it's called "CMOS-RAM", in the latter
+ * "NVRAM" (NV stands for non-volatile).
+ *
+ * The data are supplied as a (seekable) character device, /dev/nvram. The
+ * size of this file is dependent on the controller. The usual size is 114,
+ * the number of freely available bytes in the memory (i.e., not used by the
+ * RTC itself).
+ *
+ * Checksums over the NVRAM contents are managed by this driver. In case of a
+ * bad checksum, reads and writes return -EIO. The checksum can be initialized
+ * to a sane state either by ioctl(NVRAM_INIT) (clear whole NVRAM) or
+ * ioctl(NVRAM_SETCKS) (doesn't change contents, just makes checksum valid
+ * again; use with care!)
+ *
+ * 1.1 Cesar Barros: SMP locking fixes
+ * added changelog
+ * 1.2 Erik Gilling: Cobalt Networks support
+ * Tim Hockin: general cleanup, Cobalt support
+ * 1.3 Wim Van Sebroeck: convert PRINT_PROC to seq_file
+ */
+
+#define NVRAM_VERSION "1.3"
+
+#include <linux/module.h>
+#include <linux/nvram.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <linux/mc146818rtc.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/mutex.h>
+#include <linux/pagemap.h>
+
+#ifdef CONFIG_PPC
+#include <asm/nvram.h>
+#endif
+
+static DEFINE_MUTEX(nvram_mutex);
+static DEFINE_SPINLOCK(nvram_state_lock);
+static int nvram_open_cnt; /* #times opened */
+static int nvram_open_mode; /* special open modes */
+static ssize_t nvram_size;
+#define NVRAM_WRITE 1 /* opened for writing (exclusive) */
+#define NVRAM_EXCL 2 /* opened with O_EXCL */
+
+#ifdef CONFIG_X86
+/*
+ * These functions are provided to be called internally or by other parts of
+ * the kernel. It's up to the caller to ensure correct checksum before reading
+ * or after writing (needs to be done only once).
+ *
+ * It is worth noting that these functions all access bytes of general
+ * purpose memory in the NVRAM - that is to say, they all add the
+ * NVRAM_FIRST_BYTE offset. Pass them offsets into NVRAM as if you did not
+ * know about the RTC cruft.
+ */
+
+#define NVRAM_BYTES (128 - NVRAM_FIRST_BYTE)
+
+/* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with
+ * rtc_lock held. Due to the index-port/data-port design of the RTC, we
+ * don't want two different things trying to get to it at once. (e.g. the
+ * periodic 11 min sync from kernel/time/ntp.c vs. this driver.)
+ */
+
+static unsigned char __nvram_read_byte(int i)
+{
+ return CMOS_READ(NVRAM_FIRST_BYTE + i);
+}
+
+static unsigned char pc_nvram_read_byte(int i)
+{
+ unsigned long flags;
+ unsigned char c;
+
+ spin_lock_irqsave(&rtc_lock, flags);
+ c = __nvram_read_byte(i);
+ spin_unlock_irqrestore(&rtc_lock, flags);
+ return c;
+}
+
+/* This races nicely with trying to read with checksum checking (nvram_read) */
+static void __nvram_write_byte(unsigned char c, int i)
+{
+ CMOS_WRITE(c, NVRAM_FIRST_BYTE + i);
+}
+
+static void pc_nvram_write_byte(unsigned char c, int i)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtc_lock, flags);
+ __nvram_write_byte(c, i);
+ spin_unlock_irqrestore(&rtc_lock, flags);
+}
+
+/* On PCs, the checksum is built only over bytes 2..31 */
+#define PC_CKS_RANGE_START 2
+#define PC_CKS_RANGE_END 31
+#define PC_CKS_LOC 32
+
+static int __nvram_check_checksum(void)
+{
+ int i;
+ unsigned short sum = 0;
+ unsigned short expect;
+
+ for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
+ sum += __nvram_read_byte(i);
+ expect = __nvram_read_byte(PC_CKS_LOC)<<8 |
+ __nvram_read_byte(PC_CKS_LOC+1);
+ return (sum & 0xffff) == expect;
+}
+
+static void __nvram_set_checksum(void)
+{
+ int i;
+ unsigned short sum = 0;
+
+ for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
+ sum += __nvram_read_byte(i);
+ __nvram_write_byte(sum >> 8, PC_CKS_LOC);
+ __nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1);
+}
+
+static long pc_nvram_set_checksum(void)
+{
+ spin_lock_irq(&rtc_lock);
+ __nvram_set_checksum();
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+}
+
+static long pc_nvram_initialize(void)
+{
+ ssize_t i;
+
+ spin_lock_irq(&rtc_lock);
+ for (i = 0; i < NVRAM_BYTES; ++i)
+ __nvram_write_byte(0, i);
+ __nvram_set_checksum();
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+}
+
+static ssize_t pc_nvram_get_size(void)
+{
+ return NVRAM_BYTES;
+}
+
+static ssize_t pc_nvram_read(char *buf, size_t count, loff_t *ppos)
+{
+ char *p = buf;
+ loff_t i;
+
+ spin_lock_irq(&rtc_lock);
+ if (!__nvram_check_checksum()) {
+ spin_unlock_irq(&rtc_lock);
+ return -EIO;
+ }
+ for (i = *ppos; count > 0 && i < NVRAM_BYTES; --count, ++i, ++p)
+ *p = __nvram_read_byte(i);
+ spin_unlock_irq(&rtc_lock);
+
+ *ppos = i;
+ return p - buf;
+}
+
+static ssize_t pc_nvram_write(char *buf, size_t count, loff_t *ppos)
+{
+ char *p = buf;
+ loff_t i;
+
+ spin_lock_irq(&rtc_lock);
+ if (!__nvram_check_checksum()) {
+ spin_unlock_irq(&rtc_lock);
+ return -EIO;
+ }
+ for (i = *ppos; count > 0 && i < NVRAM_BYTES; --count, ++i, ++p)
+ __nvram_write_byte(*p, i);
+ __nvram_set_checksum();
+ spin_unlock_irq(&rtc_lock);
+
+ *ppos = i;
+ return p - buf;
+}
+
+const struct nvram_ops arch_nvram_ops = {
+ .read = pc_nvram_read,
+ .write = pc_nvram_write,
+ .read_byte = pc_nvram_read_byte,
+ .write_byte = pc_nvram_write_byte,
+ .get_size = pc_nvram_get_size,
+ .set_checksum = pc_nvram_set_checksum,
+ .initialize = pc_nvram_initialize,
+};
+EXPORT_SYMBOL(arch_nvram_ops);
+#endif /* CONFIG_X86 */
+
+/*
+ * The are the file operation function for user access to /dev/nvram
+ */
+
+static loff_t nvram_misc_llseek(struct file *file, loff_t offset, int origin)
+{
+ return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE,
+ nvram_size);
+}
+
+static ssize_t nvram_misc_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char *tmp;
+ ssize_t ret;
+
+
+ if (*ppos >= nvram_size)
+ return 0;
+
+ count = min_t(size_t, count, nvram_size - *ppos);
+ count = min_t(size_t, count, PAGE_SIZE);
+
+ tmp = kmalloc(count, GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+
+ ret = nvram_read(tmp, count, ppos);
+ if (ret <= 0)
+ goto out;
+
+ if (copy_to_user(buf, tmp, ret)) {
+ *ppos -= ret;
+ ret = -EFAULT;
+ }
+
+out:
+ kfree(tmp);
+ return ret;
+}
+
+static ssize_t nvram_misc_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ char *tmp;
+ ssize_t ret;
+
+ if (*ppos >= nvram_size)
+ return 0;
+
+ count = min_t(size_t, count, nvram_size - *ppos);
+ count = min_t(size_t, count, PAGE_SIZE);
+
+ tmp = memdup_user(buf, count);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
+
+ ret = nvram_write(tmp, count, ppos);
+ kfree(tmp);
+ return ret;
+}
+
+static long nvram_misc_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ long ret = -ENOTTY;
+
+ switch (cmd) {
+#ifdef CONFIG_PPC
+ case OBSOLETE_PMAC_NVRAM_GET_OFFSET:
+ pr_warn("nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n");
+ fallthrough;
+ case IOC_NVRAM_GET_OFFSET:
+ ret = -EINVAL;
+#ifdef CONFIG_PPC_PMAC
+ if (machine_is(powermac)) {
+ int part, offset;
+
+ if (copy_from_user(&part, (void __user *)arg,
+ sizeof(part)) != 0)
+ return -EFAULT;
+ if (part < pmac_nvram_OF || part > pmac_nvram_NR)
+ return -EINVAL;
+ offset = pmac_get_partition(part);
+ if (offset < 0)
+ return -EINVAL;
+ if (copy_to_user((void __user *)arg,
+ &offset, sizeof(offset)) != 0)
+ return -EFAULT;
+ ret = 0;
+ }
+#endif
+ break;
+#ifdef CONFIG_PPC32
+ case IOC_NVRAM_SYNC:
+ if (ppc_md.nvram_sync != NULL) {
+ mutex_lock(&nvram_mutex);
+ ppc_md.nvram_sync();
+ mutex_unlock(&nvram_mutex);
+ }
+ ret = 0;
+ break;
+#endif
+#elif defined(CONFIG_X86) || defined(CONFIG_M68K)
+ case NVRAM_INIT:
+ /* initialize NVRAM contents and checksum */
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (arch_nvram_ops.initialize != NULL) {
+ mutex_lock(&nvram_mutex);
+ ret = arch_nvram_ops.initialize();
+ mutex_unlock(&nvram_mutex);
+ }
+ break;
+ case NVRAM_SETCKS:
+ /* just set checksum, contents unchanged (maybe useful after
+ * checksum garbaged somehow...) */
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
+ if (arch_nvram_ops.set_checksum != NULL) {
+ mutex_lock(&nvram_mutex);
+ ret = arch_nvram_ops.set_checksum();
+ mutex_unlock(&nvram_mutex);
+ }
+ break;
+#endif /* CONFIG_X86 || CONFIG_M68K */
+ }
+ return ret;
+}
+
+static int nvram_misc_open(struct inode *inode, struct file *file)
+{
+ spin_lock(&nvram_state_lock);
+
+ /* Prevent multiple readers/writers if desired. */
+ if ((nvram_open_cnt && (file->f_flags & O_EXCL)) ||
+ (nvram_open_mode & NVRAM_EXCL)) {
+ spin_unlock(&nvram_state_lock);
+ return -EBUSY;
+ }
+
+#if defined(CONFIG_X86) || defined(CONFIG_M68K)
+ /* Prevent multiple writers if the set_checksum ioctl is implemented. */
+ if ((arch_nvram_ops.set_checksum != NULL) &&
+ (file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE)) {
+ spin_unlock(&nvram_state_lock);
+ return -EBUSY;
+ }
+#endif
+
+ if (file->f_flags & O_EXCL)
+ nvram_open_mode |= NVRAM_EXCL;
+ if (file->f_mode & FMODE_WRITE)
+ nvram_open_mode |= NVRAM_WRITE;
+ nvram_open_cnt++;
+
+ spin_unlock(&nvram_state_lock);
+
+ return 0;
+}
+
+static int nvram_misc_release(struct inode *inode, struct file *file)
+{
+ spin_lock(&nvram_state_lock);
+
+ nvram_open_cnt--;
+
+ /* if only one instance is open, clear the EXCL bit */
+ if (nvram_open_mode & NVRAM_EXCL)
+ nvram_open_mode &= ~NVRAM_EXCL;
+ if (file->f_mode & FMODE_WRITE)
+ nvram_open_mode &= ~NVRAM_WRITE;
+
+ spin_unlock(&nvram_state_lock);
+
+ return 0;
+}
+
+#if defined(CONFIG_X86) && defined(CONFIG_PROC_FS)
+static const char * const floppy_types[] = {
+ "none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M",
+ "3.5'' 2.88M", "3.5'' 2.88M"
+};
+
+static const char * const gfx_types[] = {
+ "EGA, VGA, ... (with BIOS)",
+ "CGA (40 cols)",
+ "CGA (80 cols)",
+ "monochrome",
+};
+
+static void pc_nvram_proc_read(unsigned char *nvram, struct seq_file *seq,
+ void *offset)
+{
+ int checksum;
+ int type;
+
+ spin_lock_irq(&rtc_lock);
+ checksum = __nvram_check_checksum();
+ spin_unlock_irq(&rtc_lock);
+
+ seq_printf(seq, "Checksum status: %svalid\n", checksum ? "" : "not ");
+
+ seq_printf(seq, "# floppies : %d\n",
+ (nvram[6] & 1) ? (nvram[6] >> 6) + 1 : 0);
+ seq_printf(seq, "Floppy 0 type : ");
+ type = nvram[2] >> 4;
+ if (type < ARRAY_SIZE(floppy_types))
+ seq_printf(seq, "%s\n", floppy_types[type]);
+ else
+ seq_printf(seq, "%d (unknown)\n", type);
+ seq_printf(seq, "Floppy 1 type : ");
+ type = nvram[2] & 0x0f;
+ if (type < ARRAY_SIZE(floppy_types))
+ seq_printf(seq, "%s\n", floppy_types[type]);
+ else
+ seq_printf(seq, "%d (unknown)\n", type);
+
+ seq_printf(seq, "HD 0 type : ");
+ type = nvram[4] >> 4;
+ if (type)
+ seq_printf(seq, "%02x\n", type == 0x0f ? nvram[11] : type);
+ else
+ seq_printf(seq, "none\n");
+
+ seq_printf(seq, "HD 1 type : ");
+ type = nvram[4] & 0x0f;
+ if (type)
+ seq_printf(seq, "%02x\n", type == 0x0f ? nvram[12] : type);
+ else
+ seq_printf(seq, "none\n");
+
+ seq_printf(seq, "HD type 48 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
+ nvram[18] | (nvram[19] << 8),
+ nvram[20], nvram[25],
+ nvram[21] | (nvram[22] << 8), nvram[23] | (nvram[24] << 8));
+ seq_printf(seq, "HD type 49 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
+ nvram[39] | (nvram[40] << 8),
+ nvram[41], nvram[46],
+ nvram[42] | (nvram[43] << 8), nvram[44] | (nvram[45] << 8));
+
+ seq_printf(seq, "DOS base memory: %d kB\n", nvram[7] | (nvram[8] << 8));
+ seq_printf(seq, "Extended memory: %d kB (configured), %d kB (tested)\n",
+ nvram[9] | (nvram[10] << 8), nvram[34] | (nvram[35] << 8));
+
+ seq_printf(seq, "Gfx adapter : %s\n",
+ gfx_types[(nvram[6] >> 4) & 3]);
+
+ seq_printf(seq, "FPU : %sinstalled\n",
+ (nvram[6] & 2) ? "" : "not ");
+
+ return;
+}
+
+static int nvram_proc_read(struct seq_file *seq, void *offset)
+{
+ unsigned char contents[NVRAM_BYTES];
+ int i = 0;
+
+ spin_lock_irq(&rtc_lock);
+ for (i = 0; i < NVRAM_BYTES; ++i)
+ contents[i] = __nvram_read_byte(i);
+ spin_unlock_irq(&rtc_lock);
+
+ pc_nvram_proc_read(contents, seq, offset);
+
+ return 0;
+}
+#endif /* CONFIG_X86 && CONFIG_PROC_FS */
+
+static const struct file_operations nvram_misc_fops = {
+ .owner = THIS_MODULE,
+ .llseek = nvram_misc_llseek,
+ .read = nvram_misc_read,
+ .write = nvram_misc_write,
+ .unlocked_ioctl = nvram_misc_ioctl,
+ .open = nvram_misc_open,
+ .release = nvram_misc_release,
+};
+
+static struct miscdevice nvram_misc = {
+ NVRAM_MINOR,
+ "nvram",
+ &nvram_misc_fops,
+};
+
+static int __init nvram_module_init(void)
+{
+ int ret;
+
+ nvram_size = nvram_get_size();
+ if (nvram_size < 0)
+ return nvram_size;
+
+ ret = misc_register(&nvram_misc);
+ if (ret) {
+ pr_err("nvram: can't misc_register on minor=%d\n", NVRAM_MINOR);
+ return ret;
+ }
+
+#if defined(CONFIG_X86) && defined(CONFIG_PROC_FS)
+ if (!proc_create_single("driver/nvram", 0, NULL, nvram_proc_read)) {
+ pr_err("nvram: can't create /proc/driver/nvram\n");
+ misc_deregister(&nvram_misc);
+ return -ENOMEM;
+ }
+#endif
+
+ pr_info("Non-volatile memory driver v" NVRAM_VERSION "\n");
+ return 0;
+}
+
+static void __exit nvram_module_exit(void)
+{
+#if defined(CONFIG_X86) && defined(CONFIG_PROC_FS)
+ remove_proc_entry("driver/nvram", NULL);
+#endif
+ misc_deregister(&nvram_misc);
+}
+
+module_init(nvram_module_init);
+module_exit(nvram_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(NVRAM_MINOR);
+MODULE_ALIAS("devname:nvram");