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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/intel-rng.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/char/hw_random/intel-rng.c')
-rw-r--r--drivers/char/hw_random/intel-rng.c418
1 files changed, 418 insertions, 0 deletions
diff --git a/drivers/char/hw_random/intel-rng.c b/drivers/char/hw_random/intel-rng.c
new file mode 100644
index 000000000..7b171cb3b
--- /dev/null
+++ b/drivers/char/hw_random/intel-rng.c
@@ -0,0 +1,418 @@
+/*
+ * RNG driver for Intel 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 <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/stop_machine.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+
+
+#define PFX KBUILD_MODNAME ": "
+
+/*
+ * RNG registers
+ */
+#define INTEL_RNG_HW_STATUS 0
+#define INTEL_RNG_PRESENT 0x40
+#define INTEL_RNG_ENABLED 0x01
+#define INTEL_RNG_STATUS 1
+#define INTEL_RNG_DATA_PRESENT 0x01
+#define INTEL_RNG_DATA 2
+
+/*
+ * Magic address at which Intel PCI bridges locate the RNG
+ */
+#define INTEL_RNG_ADDR 0xFFBC015F
+#define INTEL_RNG_ADDR_LEN 3
+
+/*
+ * LPC bridge PCI config space registers
+ */
+#define FWH_DEC_EN1_REG_OLD 0xe3
+#define FWH_DEC_EN1_REG_NEW 0xd9 /* high byte of 16-bit register */
+#define FWH_F8_EN_MASK 0x80
+
+#define BIOS_CNTL_REG_OLD 0x4e
+#define BIOS_CNTL_REG_NEW 0xdc
+#define BIOS_CNTL_WRITE_ENABLE_MASK 0x01
+#define BIOS_CNTL_LOCK_ENABLE_MASK 0x02
+
+/*
+ * Magic address at which Intel Firmware Hubs get accessed
+ */
+#define INTEL_FWH_ADDR 0xffff0000
+#define INTEL_FWH_ADDR_LEN 2
+
+/*
+ * Intel Firmware Hub command codes (write to any address inside the device)
+ */
+#define INTEL_FWH_RESET_CMD 0xff /* aka READ_ARRAY */
+#define INTEL_FWH_READ_ID_CMD 0x90
+
+/*
+ * Intel Firmware Hub Read ID command result addresses
+ */
+#define INTEL_FWH_MANUFACTURER_CODE_ADDRESS 0x000000
+#define INTEL_FWH_DEVICE_CODE_ADDRESS 0x000001
+
+/*
+ * Intel Firmware Hub Read ID command result values
+ */
+#define INTEL_FWH_MANUFACTURER_CODE 0x89
+#define INTEL_FWH_DEVICE_CODE_8M 0xac
+#define INTEL_FWH_DEVICE_CODE_4M 0xad
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE. We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id pci_tbl[] = {
+/* AA
+ { PCI_DEVICE(0x8086, 0x2418) }, */
+ { PCI_DEVICE(0x8086, 0x2410) }, /* AA */
+/* AB
+ { PCI_DEVICE(0x8086, 0x2428) }, */
+ { PCI_DEVICE(0x8086, 0x2420) }, /* AB */
+/* ??
+ { PCI_DEVICE(0x8086, 0x2430) }, */
+/* BAM, CAM, DBM, FBM, GxM
+ { PCI_DEVICE(0x8086, 0x2448) }, */
+ { PCI_DEVICE(0x8086, 0x244c) }, /* BAM */
+ { PCI_DEVICE(0x8086, 0x248c) }, /* CAM */
+ { PCI_DEVICE(0x8086, 0x24cc) }, /* DBM */
+ { PCI_DEVICE(0x8086, 0x2641) }, /* FBM */
+ { PCI_DEVICE(0x8086, 0x27b9) }, /* GxM */
+ { PCI_DEVICE(0x8086, 0x27bd) }, /* GxM DH */
+/* BA, CA, DB, Ex, 6300, Fx, 631x/632x, Gx
+ { PCI_DEVICE(0x8086, 0x244e) }, */
+ { PCI_DEVICE(0x8086, 0x2440) }, /* BA */
+ { PCI_DEVICE(0x8086, 0x2480) }, /* CA */
+ { PCI_DEVICE(0x8086, 0x24c0) }, /* DB */
+ { PCI_DEVICE(0x8086, 0x24d0) }, /* Ex */
+ { PCI_DEVICE(0x8086, 0x25a1) }, /* 6300 */
+ { PCI_DEVICE(0x8086, 0x2640) }, /* Fx */
+ { PCI_DEVICE(0x8086, 0x2670) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2671) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2672) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2673) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2674) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2675) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2676) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2677) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2678) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x2679) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x267a) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x267b) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x267c) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x267d) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x267e) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x267f) }, /* 631x/632x */
+ { PCI_DEVICE(0x8086, 0x27b8) }, /* Gx */
+/* E
+ { PCI_DEVICE(0x8086, 0x245e) }, */
+ { PCI_DEVICE(0x8086, 0x2450) }, /* E */
+ { 0, }, /* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, pci_tbl);
+
+static __initdata int no_fwh_detect;
+module_param(no_fwh_detect, int, 0);
+MODULE_PARM_DESC(no_fwh_detect, "Skip FWH detection:\n"
+ " positive value - skip if FWH space locked read-only\n"
+ " negative value - skip always");
+
+static inline u8 hwstatus_get(void __iomem *mem)
+{
+ return readb(mem + INTEL_RNG_HW_STATUS);
+}
+
+static inline u8 hwstatus_set(void __iomem *mem,
+ u8 hw_status)
+{
+ writeb(hw_status, mem + INTEL_RNG_HW_STATUS);
+ return hwstatus_get(mem);
+}
+
+static int intel_rng_data_present(struct hwrng *rng, int wait)
+{
+ void __iomem *mem = (void __iomem *)rng->priv;
+ int data, i;
+
+ for (i = 0; i < 20; i++) {
+ data = !!(readb(mem + INTEL_RNG_STATUS) &
+ INTEL_RNG_DATA_PRESENT);
+ if (data || !wait)
+ break;
+ udelay(10);
+ }
+ return data;
+}
+
+static int intel_rng_data_read(struct hwrng *rng, u32 *data)
+{
+ void __iomem *mem = (void __iomem *)rng->priv;
+
+ *data = readb(mem + INTEL_RNG_DATA);
+
+ return 1;
+}
+
+static int intel_rng_init(struct hwrng *rng)
+{
+ void __iomem *mem = (void __iomem *)rng->priv;
+ u8 hw_status;
+ int err = -EIO;
+
+ hw_status = hwstatus_get(mem);
+ /* turn RNG h/w on, if it's off */
+ if ((hw_status & INTEL_RNG_ENABLED) == 0)
+ hw_status = hwstatus_set(mem, hw_status | INTEL_RNG_ENABLED);
+ if ((hw_status & INTEL_RNG_ENABLED) == 0) {
+ pr_err(PFX "cannot enable RNG, aborting\n");
+ goto out;
+ }
+ err = 0;
+out:
+ return err;
+}
+
+static void intel_rng_cleanup(struct hwrng *rng)
+{
+ void __iomem *mem = (void __iomem *)rng->priv;
+ u8 hw_status;
+
+ hw_status = hwstatus_get(mem);
+ if (hw_status & INTEL_RNG_ENABLED)
+ hwstatus_set(mem, hw_status & ~INTEL_RNG_ENABLED);
+ else
+ pr_warn(PFX "unusual: RNG already disabled\n");
+}
+
+
+static struct hwrng intel_rng = {
+ .name = "intel",
+ .init = intel_rng_init,
+ .cleanup = intel_rng_cleanup,
+ .data_present = intel_rng_data_present,
+ .data_read = intel_rng_data_read,
+};
+
+struct intel_rng_hw {
+ struct pci_dev *dev;
+ void __iomem *mem;
+ u8 bios_cntl_off;
+ u8 bios_cntl_val;
+ u8 fwh_dec_en1_off;
+ u8 fwh_dec_en1_val;
+};
+
+static int __init intel_rng_hw_init(void *_intel_rng_hw)
+{
+ struct intel_rng_hw *intel_rng_hw = _intel_rng_hw;
+ u8 mfc, dvc;
+
+ /* interrupts disabled in stop_machine call */
+
+ if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK))
+ pci_write_config_byte(intel_rng_hw->dev,
+ intel_rng_hw->fwh_dec_en1_off,
+ intel_rng_hw->fwh_dec_en1_val |
+ FWH_F8_EN_MASK);
+ if (!(intel_rng_hw->bios_cntl_val & BIOS_CNTL_WRITE_ENABLE_MASK))
+ pci_write_config_byte(intel_rng_hw->dev,
+ intel_rng_hw->bios_cntl_off,
+ intel_rng_hw->bios_cntl_val |
+ BIOS_CNTL_WRITE_ENABLE_MASK);
+
+ writeb(INTEL_FWH_RESET_CMD, intel_rng_hw->mem);
+ writeb(INTEL_FWH_READ_ID_CMD, intel_rng_hw->mem);
+ mfc = readb(intel_rng_hw->mem + INTEL_FWH_MANUFACTURER_CODE_ADDRESS);
+ dvc = readb(intel_rng_hw->mem + INTEL_FWH_DEVICE_CODE_ADDRESS);
+ writeb(INTEL_FWH_RESET_CMD, intel_rng_hw->mem);
+
+ if (!(intel_rng_hw->bios_cntl_val &
+ (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK)))
+ pci_write_config_byte(intel_rng_hw->dev,
+ intel_rng_hw->bios_cntl_off,
+ intel_rng_hw->bios_cntl_val);
+ if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK))
+ pci_write_config_byte(intel_rng_hw->dev,
+ intel_rng_hw->fwh_dec_en1_off,
+ intel_rng_hw->fwh_dec_en1_val);
+
+ if (mfc != INTEL_FWH_MANUFACTURER_CODE ||
+ (dvc != INTEL_FWH_DEVICE_CODE_8M &&
+ dvc != INTEL_FWH_DEVICE_CODE_4M)) {
+ pr_notice(PFX "FWH not detected\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int __init intel_init_hw_struct(struct intel_rng_hw *intel_rng_hw,
+ struct pci_dev *dev)
+{
+ intel_rng_hw->bios_cntl_val = 0xff;
+ intel_rng_hw->fwh_dec_en1_val = 0xff;
+ intel_rng_hw->dev = dev;
+
+ /* Check for Intel 82802 */
+ if (dev->device < 0x2640) {
+ intel_rng_hw->fwh_dec_en1_off = FWH_DEC_EN1_REG_OLD;
+ intel_rng_hw->bios_cntl_off = BIOS_CNTL_REG_OLD;
+ } else {
+ intel_rng_hw->fwh_dec_en1_off = FWH_DEC_EN1_REG_NEW;
+ intel_rng_hw->bios_cntl_off = BIOS_CNTL_REG_NEW;
+ }
+
+ pci_read_config_byte(dev, intel_rng_hw->fwh_dec_en1_off,
+ &intel_rng_hw->fwh_dec_en1_val);
+ pci_read_config_byte(dev, intel_rng_hw->bios_cntl_off,
+ &intel_rng_hw->bios_cntl_val);
+
+ if ((intel_rng_hw->bios_cntl_val &
+ (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK))
+ == BIOS_CNTL_LOCK_ENABLE_MASK) {
+ static __initdata /*const*/ char warning[] =
+PFX "Firmware space is locked read-only. If you can't or\n"
+PFX "don't want to disable this in firmware setup, and if\n"
+PFX "you are certain that your system has a functional\n"
+PFX "RNG, try using the 'no_fwh_detect' option.\n";
+
+ if (no_fwh_detect)
+ return -ENODEV;
+ pr_warn("%s", warning);
+ return -EBUSY;
+ }
+
+ intel_rng_hw->mem = ioremap(INTEL_FWH_ADDR, INTEL_FWH_ADDR_LEN);
+ if (intel_rng_hw->mem == NULL)
+ return -EBUSY;
+
+ return 0;
+}
+
+
+static int __init intel_rng_mod_init(void)
+{
+ int err = -ENODEV;
+ int i;
+ struct pci_dev *dev = NULL;
+ void __iomem *mem;
+ u8 hw_status;
+ struct intel_rng_hw *intel_rng_hw;
+
+ for (i = 0; !dev && pci_tbl[i].vendor; ++i)
+ dev = pci_get_device(pci_tbl[i].vendor, pci_tbl[i].device,
+ NULL);
+
+ if (!dev)
+ goto out; /* Device not found. */
+
+ if (no_fwh_detect < 0) {
+ pci_dev_put(dev);
+ goto fwh_done;
+ }
+
+ intel_rng_hw = kmalloc(sizeof(*intel_rng_hw), GFP_KERNEL);
+ if (!intel_rng_hw) {
+ pci_dev_put(dev);
+ goto out;
+ }
+
+ err = intel_init_hw_struct(intel_rng_hw, dev);
+ if (err) {
+ pci_dev_put(dev);
+ kfree(intel_rng_hw);
+ if (err == -ENODEV)
+ goto fwh_done;
+ goto out;
+ }
+
+ /*
+ * Since the BIOS code/data is going to disappear from its normal
+ * location with the Read ID command, all activity on the system
+ * must be stopped until the state is back to normal.
+ *
+ * Use stop_machine because IPIs can be blocked by disabling
+ * interrupts.
+ */
+ err = stop_machine(intel_rng_hw_init, intel_rng_hw, NULL);
+ pci_dev_put(dev);
+ iounmap(intel_rng_hw->mem);
+ kfree(intel_rng_hw);
+ if (err)
+ goto out;
+
+fwh_done:
+ err = -ENOMEM;
+ mem = ioremap(INTEL_RNG_ADDR, INTEL_RNG_ADDR_LEN);
+ if (!mem)
+ goto out;
+ intel_rng.priv = (unsigned long)mem;
+
+ /* Check for Random Number Generator */
+ err = -ENODEV;
+ hw_status = hwstatus_get(mem);
+ if ((hw_status & INTEL_RNG_PRESENT) == 0) {
+ iounmap(mem);
+ goto out;
+ }
+
+ pr_info("Intel 82802 RNG detected\n");
+ err = hwrng_register(&intel_rng);
+ if (err) {
+ pr_err(PFX "RNG registering failed (%d)\n",
+ err);
+ iounmap(mem);
+ }
+out:
+ return err;
+
+}
+
+static void __exit intel_rng_mod_exit(void)
+{
+ void __iomem *mem = (void __iomem *)intel_rng.priv;
+
+ hwrng_unregister(&intel_rng);
+ iounmap(mem);
+}
+
+module_init(intel_rng_mod_init);
+module_exit(intel_rng_mod_exit);
+
+MODULE_DESCRIPTION("H/W RNG driver for Intel chipsets");
+MODULE_LICENSE("GPL");