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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/hw_random/via-rng.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/hw_random/via-rng.c')
-rw-r--r--drivers/char/hw_random/via-rng.c227
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/char/hw_random/via-rng.c b/drivers/char/hw_random/via-rng.c
new file mode 100644
index 000000000..a9a0a3b09
--- /dev/null
+++ b/drivers/char/hw_random/via-rng.c
@@ -0,0 +1,227 @@
+/*
+ * RNG driver for VIA RNGs
+ *
+ * Copyright 2005 (c) MontaVista Software, Inc.
+ *
+ * with the majority of the code coming from:
+ *
+ * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
+ * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
+ *
+ * derived from
+ *
+ * Hardware driver for the AMD 768 Random Number Generator (RNG)
+ * (c) Copyright 2001 Red Hat Inc
+ *
+ * derived from
+ *
+ * Hardware driver for Intel i810 Random Number Generator (RNG)
+ * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
+ * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <crypto/padlock.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/hw_random.h>
+#include <linux/delay.h>
+#include <asm/cpu_device_id.h>
+#include <asm/io.h>
+#include <asm/msr.h>
+#include <asm/cpufeature.h>
+#include <asm/fpu/api.h>
+
+
+
+
+enum {
+ VIA_STRFILT_CNT_SHIFT = 16,
+ VIA_STRFILT_FAIL = (1 << 15),
+ VIA_STRFILT_ENABLE = (1 << 14),
+ VIA_RAWBITS_ENABLE = (1 << 13),
+ VIA_RNG_ENABLE = (1 << 6),
+ VIA_NOISESRC1 = (1 << 8),
+ VIA_NOISESRC2 = (1 << 9),
+ VIA_XSTORE_CNT_MASK = 0x0F,
+
+ VIA_RNG_CHUNK_8 = 0x00, /* 64 rand bits, 64 stored bits */
+ VIA_RNG_CHUNK_4 = 0x01, /* 32 rand bits, 32 stored bits */
+ VIA_RNG_CHUNK_4_MASK = 0xFFFFFFFF,
+ VIA_RNG_CHUNK_2 = 0x02, /* 16 rand bits, 32 stored bits */
+ VIA_RNG_CHUNK_2_MASK = 0xFFFF,
+ VIA_RNG_CHUNK_1 = 0x03, /* 8 rand bits, 32 stored bits */
+ VIA_RNG_CHUNK_1_MASK = 0xFF,
+};
+
+/*
+ * Investigate using the 'rep' prefix to obtain 32 bits of random data
+ * in one insn. The upside is potentially better performance. The
+ * downside is that the instruction becomes no longer atomic. Due to
+ * this, just like familiar issues with /dev/random itself, the worst
+ * case of a 'rep xstore' could potentially pause a cpu for an
+ * unreasonably long time. In practice, this condition would likely
+ * only occur when the hardware is failing. (or so we hope :))
+ *
+ * Another possible performance boost may come from simply buffering
+ * until we have 4 bytes, thus returning a u32 at a time,
+ * instead of the current u8-at-a-time.
+ *
+ * Padlock instructions can generate a spurious DNA fault, but the
+ * kernel doesn't use CR0.TS, so this doesn't matter.
+ */
+
+static inline u32 xstore(u32 *addr, u32 edx_in)
+{
+ u32 eax_out;
+
+ asm(".byte 0x0F,0xA7,0xC0 /* xstore %%edi (addr=%0) */"
+ : "=m" (*addr), "=a" (eax_out), "+d" (edx_in), "+D" (addr));
+
+ return eax_out;
+}
+
+static int via_rng_data_present(struct hwrng *rng, int wait)
+{
+ char buf[16 + PADLOCK_ALIGNMENT - STACK_ALIGN] __attribute__
+ ((aligned(STACK_ALIGN)));
+ u32 *via_rng_datum = (u32 *)PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT);
+ u32 bytes_out;
+ int i;
+
+ /* We choose the recommended 1-byte-per-instruction RNG rate,
+ * for greater randomness at the expense of speed. Larger
+ * values 2, 4, or 8 bytes-per-instruction yield greater
+ * speed at lesser randomness.
+ *
+ * If you change this to another VIA_CHUNK_n, you must also
+ * change the ->n_bytes values in rng_vendor_ops[] tables.
+ * VIA_CHUNK_8 requires further code changes.
+ *
+ * A copy of MSR_VIA_RNG is placed in eax_out when xstore
+ * completes.
+ */
+
+ for (i = 0; i < 20; i++) {
+ *via_rng_datum = 0; /* paranoia, not really necessary */
+ bytes_out = xstore(via_rng_datum, VIA_RNG_CHUNK_1);
+ bytes_out &= VIA_XSTORE_CNT_MASK;
+ if (bytes_out || !wait)
+ break;
+ udelay(10);
+ }
+ rng->priv = *via_rng_datum;
+ return bytes_out ? 1 : 0;
+}
+
+static int via_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ u32 via_rng_datum = (u32)rng->priv;
+
+ *data = via_rng_datum;
+
+ return 1;
+}
+
+static int via_rng_init(struct hwrng *rng)
+{
+ struct cpuinfo_x86 *c = &cpu_data(0);
+ u32 lo, hi, old_lo;
+
+ /* VIA Nano CPUs don't have the MSR_VIA_RNG anymore. The RNG
+ * is always enabled if CPUID rng_en is set. There is no
+ * RNG configuration like it used to be the case in this
+ * register */
+ if (((c->x86 == 6) && (c->x86_model >= 0x0f)) || (c->x86 > 6)){
+ if (!boot_cpu_has(X86_FEATURE_XSTORE_EN)) {
+ pr_err(PFX "can't enable hardware RNG "
+ "if XSTORE is not enabled\n");
+ return -ENODEV;
+ }
+ return 0;
+ }
+
+ /* Control the RNG via MSR. Tread lightly and pay very close
+ * attention to values written, as the reserved fields
+ * are documented to be "undefined and unpredictable"; but it
+ * does not say to write them as zero, so I make a guess that
+ * we restore the values we find in the register.
+ */
+ rdmsr(MSR_VIA_RNG, lo, hi);
+
+ old_lo = lo;
+ lo &= ~(0x7f << VIA_STRFILT_CNT_SHIFT);
+ lo &= ~VIA_XSTORE_CNT_MASK;
+ lo &= ~(VIA_STRFILT_ENABLE | VIA_STRFILT_FAIL | VIA_RAWBITS_ENABLE);
+ lo |= VIA_RNG_ENABLE;
+ lo |= VIA_NOISESRC1;
+
+ /* Enable secondary noise source on CPUs where it is present. */
+
+ /* Nehemiah stepping 8 and higher */
+ if ((c->x86_model == 9) && (c->x86_stepping > 7))
+ lo |= VIA_NOISESRC2;
+
+ /* Esther */
+ if (c->x86_model >= 10)
+ lo |= VIA_NOISESRC2;
+
+ if (lo != old_lo)
+ wrmsr(MSR_VIA_RNG, lo, hi);
+
+ /* perhaps-unnecessary sanity check; remove after testing if
+ unneeded */
+ rdmsr(MSR_VIA_RNG, lo, hi);
+ if ((lo & VIA_RNG_ENABLE) == 0) {
+ pr_err(PFX "cannot enable VIA C3 RNG, aborting\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+
+static struct hwrng via_rng = {
+ .name = "via",
+ .init = via_rng_init,
+ .data_present = via_rng_data_present,
+ .data_read = via_rng_data_read,
+};
+
+
+static int __init via_rng_mod_init(void)
+{
+ int err;
+
+ if (!boot_cpu_has(X86_FEATURE_XSTORE))
+ return -ENODEV;
+
+ pr_info("VIA RNG detected\n");
+ err = hwrng_register(&via_rng);
+ if (err) {
+ pr_err(PFX "RNG registering failed (%d)\n",
+ err);
+ goto out;
+ }
+out:
+ return err;
+}
+module_init(via_rng_mod_init);
+
+static void __exit via_rng_mod_exit(void)
+{
+ hwrng_unregister(&via_rng);
+}
+module_exit(via_rng_mod_exit);
+
+static struct x86_cpu_id __maybe_unused via_rng_cpu_id[] = {
+ X86_MATCH_FEATURE(X86_FEATURE_XSTORE, NULL),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, via_rng_cpu_id);
+
+MODULE_DESCRIPTION("H/W RNG driver for VIA CPU with PadLock");
+MODULE_LICENSE("GPL");