From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- drivers/platform/x86/dell/dcdbas.c | 782 +++++++++++++++++++++++++++++++++++++ 1 file changed, 782 insertions(+) create mode 100644 drivers/platform/x86/dell/dcdbas.c (limited to 'drivers/platform/x86/dell/dcdbas.c') diff --git a/drivers/platform/x86/dell/dcdbas.c b/drivers/platform/x86/dell/dcdbas.c new file mode 100644 index 000000000..0ecb7b164 --- /dev/null +++ b/drivers/platform/x86/dell/dcdbas.c @@ -0,0 +1,782 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * dcdbas.c: Dell Systems Management Base Driver + * + * The Dell Systems Management Base Driver provides a sysfs interface for + * systems management software to perform System Management Interrupts (SMIs) + * and Host Control Actions (power cycle or power off after OS shutdown) on + * Dell systems. + * + * See Documentation/driver-api/dcdbas.rst for more information. + * + * Copyright (C) 1995-2006 Dell Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "dcdbas.h" + +#define DRIVER_NAME "dcdbas" +#define DRIVER_VERSION "5.6.0-3.4" +#define DRIVER_DESCRIPTION "Dell Systems Management Base Driver" + +static struct platform_device *dcdbas_pdev; + +static unsigned long max_smi_data_buf_size = MAX_SMI_DATA_BUF_SIZE; +static DEFINE_MUTEX(smi_data_lock); +static u8 *bios_buffer; +static struct smi_buffer smi_buf; + +static unsigned int host_control_action; +static unsigned int host_control_smi_type; +static unsigned int host_control_on_shutdown; + +static bool wsmt_enabled; + +int dcdbas_smi_alloc(struct smi_buffer *smi_buffer, unsigned long size) +{ + smi_buffer->virt = dma_alloc_coherent(&dcdbas_pdev->dev, size, + &smi_buffer->dma, GFP_KERNEL); + if (!smi_buffer->virt) { + dev_dbg(&dcdbas_pdev->dev, + "%s: failed to allocate memory size %lu\n", + __func__, size); + return -ENOMEM; + } + smi_buffer->size = size; + + dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", + __func__, (u32)smi_buffer->dma, smi_buffer->size); + + return 0; +} +EXPORT_SYMBOL_GPL(dcdbas_smi_alloc); + +void dcdbas_smi_free(struct smi_buffer *smi_buffer) +{ + if (!smi_buffer->virt) + return; + + dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", + __func__, (u32)smi_buffer->dma, smi_buffer->size); + dma_free_coherent(&dcdbas_pdev->dev, smi_buffer->size, + smi_buffer->virt, smi_buffer->dma); + smi_buffer->virt = NULL; + smi_buffer->dma = 0; + smi_buffer->size = 0; +} +EXPORT_SYMBOL_GPL(dcdbas_smi_free); + +/** + * smi_data_buf_free: free SMI data buffer + */ +static void smi_data_buf_free(void) +{ + if (!smi_buf.virt || wsmt_enabled) + return; + + dcdbas_smi_free(&smi_buf); +} + +/** + * smi_data_buf_realloc: grow SMI data buffer if needed + */ +static int smi_data_buf_realloc(unsigned long size) +{ + struct smi_buffer tmp; + int ret; + + if (smi_buf.size >= size) + return 0; + + if (size > max_smi_data_buf_size) + return -EINVAL; + + /* new buffer is needed */ + ret = dcdbas_smi_alloc(&tmp, size); + if (ret) + return ret; + + /* memory zeroed by dma_alloc_coherent */ + if (smi_buf.virt) + memcpy(tmp.virt, smi_buf.virt, smi_buf.size); + + /* free any existing buffer */ + smi_data_buf_free(); + + /* set up new buffer for use */ + smi_buf = tmp; + + return 0; +} + +static ssize_t smi_data_buf_phys_addr_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%x\n", (u32)smi_buf.dma); +} + +static ssize_t smi_data_buf_size_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%lu\n", smi_buf.size); +} + +static ssize_t smi_data_buf_size_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + unsigned long buf_size; + ssize_t ret; + + buf_size = simple_strtoul(buf, NULL, 10); + + /* make sure SMI data buffer is at least buf_size */ + mutex_lock(&smi_data_lock); + ret = smi_data_buf_realloc(buf_size); + mutex_unlock(&smi_data_lock); + if (ret) + return ret; + + return count; +} + +static ssize_t smi_data_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + ssize_t ret; + + mutex_lock(&smi_data_lock); + ret = memory_read_from_buffer(buf, count, &pos, smi_buf.virt, + smi_buf.size); + mutex_unlock(&smi_data_lock); + return ret; +} + +static ssize_t smi_data_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t pos, size_t count) +{ + ssize_t ret; + + if ((pos + count) > max_smi_data_buf_size) + return -EINVAL; + + mutex_lock(&smi_data_lock); + + ret = smi_data_buf_realloc(pos + count); + if (ret) + goto out; + + memcpy(smi_buf.virt + pos, buf, count); + ret = count; +out: + mutex_unlock(&smi_data_lock); + return ret; +} + +static ssize_t host_control_action_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%u\n", host_control_action); +} + +static ssize_t host_control_action_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + ssize_t ret; + + /* make sure buffer is available for host control command */ + mutex_lock(&smi_data_lock); + ret = smi_data_buf_realloc(sizeof(struct apm_cmd)); + mutex_unlock(&smi_data_lock); + if (ret) + return ret; + + host_control_action = simple_strtoul(buf, NULL, 10); + return count; +} + +static ssize_t host_control_smi_type_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%u\n", host_control_smi_type); +} + +static ssize_t host_control_smi_type_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + host_control_smi_type = simple_strtoul(buf, NULL, 10); + return count; +} + +static ssize_t host_control_on_shutdown_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%u\n", host_control_on_shutdown); +} + +static ssize_t host_control_on_shutdown_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + host_control_on_shutdown = simple_strtoul(buf, NULL, 10); + return count; +} + +static int raise_smi(void *par) +{ + struct smi_cmd *smi_cmd = par; + + if (smp_processor_id() != 0) { + dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n", + __func__); + return -EBUSY; + } + + /* generate SMI */ + /* inb to force posted write through and make SMI happen now */ + asm volatile ( + "outb %b0,%w1\n" + "inb %w1" + : /* no output args */ + : "a" (smi_cmd->command_code), + "d" (smi_cmd->command_address), + "b" (smi_cmd->ebx), + "c" (smi_cmd->ecx) + : "memory" + ); + + return 0; +} +/** + * dcdbas_smi_request: generate SMI request + * + * Called with smi_data_lock. + */ +int dcdbas_smi_request(struct smi_cmd *smi_cmd) +{ + int ret; + + if (smi_cmd->magic != SMI_CMD_MAGIC) { + dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n", + __func__); + return -EBADR; + } + + /* SMI requires CPU 0 */ + cpus_read_lock(); + ret = smp_call_on_cpu(0, raise_smi, smi_cmd, true); + cpus_read_unlock(); + + return ret; +} +EXPORT_SYMBOL(dcdbas_smi_request); + +/** + * smi_request_store: + * + * The valid values are: + * 0: zero SMI data buffer + * 1: generate calling interface SMI + * 2: generate raw SMI + * + * User application writes smi_cmd to smi_data before telling driver + * to generate SMI. + */ +static ssize_t smi_request_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct smi_cmd *smi_cmd; + unsigned long val = simple_strtoul(buf, NULL, 10); + ssize_t ret; + + mutex_lock(&smi_data_lock); + + if (smi_buf.size < sizeof(struct smi_cmd)) { + ret = -ENODEV; + goto out; + } + smi_cmd = (struct smi_cmd *)smi_buf.virt; + + switch (val) { + case 2: + /* Raw SMI */ + ret = dcdbas_smi_request(smi_cmd); + if (!ret) + ret = count; + break; + case 1: + /* + * Calling Interface SMI + * + * Provide physical address of command buffer field within + * the struct smi_cmd to BIOS. + * + * Because the address that smi_cmd (smi_buf.virt) points to + * will be from memremap() of a non-memory address if WSMT + * is present, we can't use virt_to_phys() on smi_cmd, so + * we have to use the physical address that was saved when + * the virtual address for smi_cmd was received. + */ + smi_cmd->ebx = (u32)smi_buf.dma + + offsetof(struct smi_cmd, command_buffer); + ret = dcdbas_smi_request(smi_cmd); + if (!ret) + ret = count; + break; + case 0: + memset(smi_buf.virt, 0, smi_buf.size); + ret = count; + break; + default: + ret = -EINVAL; + break; + } + +out: + mutex_unlock(&smi_data_lock); + return ret; +} + +/** + * host_control_smi: generate host control SMI + * + * Caller must set up the host control command in smi_buf.virt. + */ +static int host_control_smi(void) +{ + struct apm_cmd *apm_cmd; + u8 *data; + unsigned long flags; + u32 num_ticks; + s8 cmd_status; + u8 index; + + apm_cmd = (struct apm_cmd *)smi_buf.virt; + apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL; + + switch (host_control_smi_type) { + case HC_SMITYPE_TYPE1: + spin_lock_irqsave(&rtc_lock, flags); + /* write SMI data buffer physical address */ + data = (u8 *)&smi_buf.dma; + for (index = PE1300_CMOS_CMD_STRUCT_PTR; + index < (PE1300_CMOS_CMD_STRUCT_PTR + 4); + index++, data++) { + outb(index, + (CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4)); + outb(*data, + (CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4)); + } + + /* first set status to -1 as called by spec */ + cmd_status = ESM_STATUS_CMD_UNSUCCESSFUL; + outb((u8) cmd_status, PCAT_APM_STATUS_PORT); + + /* generate SMM call */ + outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT); + spin_unlock_irqrestore(&rtc_lock, flags); + + /* wait a few to see if it executed */ + num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING; + while ((s8)inb(PCAT_APM_STATUS_PORT) == ESM_STATUS_CMD_UNSUCCESSFUL) { + num_ticks--; + if (num_ticks == EXPIRED_TIMER) + return -ETIME; + } + break; + + case HC_SMITYPE_TYPE2: + case HC_SMITYPE_TYPE3: + spin_lock_irqsave(&rtc_lock, flags); + /* write SMI data buffer physical address */ + data = (u8 *)&smi_buf.dma; + for (index = PE1400_CMOS_CMD_STRUCT_PTR; + index < (PE1400_CMOS_CMD_STRUCT_PTR + 4); + index++, data++) { + outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT)); + outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT)); + } + + /* generate SMM call */ + if (host_control_smi_type == HC_SMITYPE_TYPE3) + outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT); + else + outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT); + + /* restore RTC index pointer since it was written to above */ + CMOS_READ(RTC_REG_C); + spin_unlock_irqrestore(&rtc_lock, flags); + + /* read control port back to serialize write */ + cmd_status = inb(PE1400_APM_CONTROL_PORT); + + /* wait a few to see if it executed */ + num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING; + while (apm_cmd->status == ESM_STATUS_CMD_UNSUCCESSFUL) { + num_ticks--; + if (num_ticks == EXPIRED_TIMER) + return -ETIME; + } + break; + + default: + dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n", + __func__, host_control_smi_type); + return -ENOSYS; + } + + return 0; +} + +/** + * dcdbas_host_control: initiate host control + * + * This function is called by the driver after the system has + * finished shutting down if the user application specified a + * host control action to perform on shutdown. It is safe to + * use smi_buf.virt at this point because the system has finished + * shutting down and no userspace apps are running. + */ +static void dcdbas_host_control(void) +{ + struct apm_cmd *apm_cmd; + u8 action; + + if (host_control_action == HC_ACTION_NONE) + return; + + action = host_control_action; + host_control_action = HC_ACTION_NONE; + + if (!smi_buf.virt) { + dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__); + return; + } + + if (smi_buf.size < sizeof(struct apm_cmd)) { + dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n", + __func__); + return; + } + + apm_cmd = (struct apm_cmd *)smi_buf.virt; + + /* power off takes precedence */ + if (action & HC_ACTION_HOST_CONTROL_POWEROFF) { + apm_cmd->command = ESM_APM_POWER_CYCLE; + apm_cmd->reserved = 0; + *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 0; + host_control_smi(); + } else if (action & HC_ACTION_HOST_CONTROL_POWERCYCLE) { + apm_cmd->command = ESM_APM_POWER_CYCLE; + apm_cmd->reserved = 0; + *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 20; + host_control_smi(); + } +} + +/* WSMT */ + +static u8 checksum(u8 *buffer, u8 length) +{ + u8 sum = 0; + u8 *end = buffer + length; + + while (buffer < end) + sum += *buffer++; + return sum; +} + +static inline struct smm_eps_table *check_eps_table(u8 *addr) +{ + struct smm_eps_table *eps = (struct smm_eps_table *)addr; + + if (strncmp(eps->smm_comm_buff_anchor, SMM_EPS_SIG, 4) != 0) + return NULL; + + if (checksum(addr, eps->length) != 0) + return NULL; + + return eps; +} + +static int dcdbas_check_wsmt(void) +{ + const struct dmi_device *dev = NULL; + struct acpi_table_wsmt *wsmt = NULL; + struct smm_eps_table *eps = NULL; + u64 bios_buf_paddr; + u64 remap_size; + u8 *addr; + + acpi_get_table(ACPI_SIG_WSMT, 0, (struct acpi_table_header **)&wsmt); + if (!wsmt) + return 0; + + /* Check if WSMT ACPI table shows that protection is enabled */ + if (!(wsmt->protection_flags & ACPI_WSMT_FIXED_COMM_BUFFERS) || + !(wsmt->protection_flags & ACPI_WSMT_COMM_BUFFER_NESTED_PTR_PROTECTION)) + return 0; + + /* + * BIOS could provide the address/size of the protected buffer + * in an SMBIOS string or in an EPS structure in 0xFxxxx. + */ + + /* Check SMBIOS for buffer address */ + while ((dev = dmi_find_device(DMI_DEV_TYPE_OEM_STRING, NULL, dev))) + if (sscanf(dev->name, "30[%16llx;%8llx]", &bios_buf_paddr, + &remap_size) == 2) + goto remap; + + /* Scan for EPS (entry point structure) */ + for (addr = (u8 *)__va(0xf0000); + addr < (u8 *)__va(0x100000 - sizeof(struct smm_eps_table)); + addr += 16) { + eps = check_eps_table(addr); + if (eps) + break; + } + + if (!eps) { + dev_dbg(&dcdbas_pdev->dev, "found WSMT, but no firmware buffer found\n"); + return -ENODEV; + } + bios_buf_paddr = eps->smm_comm_buff_addr; + remap_size = eps->num_of_4k_pages * PAGE_SIZE; + +remap: + /* + * Get physical address of buffer and map to virtual address. + * Table gives size in 4K pages, regardless of actual system page size. + */ + if (upper_32_bits(bios_buf_paddr + 8)) { + dev_warn(&dcdbas_pdev->dev, "found WSMT, but buffer address is above 4GB\n"); + return -EINVAL; + } + /* + * Limit remap size to MAX_SMI_DATA_BUF_SIZE + 8 (since the first 8 + * bytes are used for a semaphore, not the data buffer itself). + */ + if (remap_size > MAX_SMI_DATA_BUF_SIZE + 8) + remap_size = MAX_SMI_DATA_BUF_SIZE + 8; + + bios_buffer = memremap(bios_buf_paddr, remap_size, MEMREMAP_WB); + if (!bios_buffer) { + dev_warn(&dcdbas_pdev->dev, "found WSMT, but failed to map buffer\n"); + return -ENOMEM; + } + + /* First 8 bytes is for a semaphore, not part of the smi_buf.virt */ + smi_buf.dma = bios_buf_paddr + 8; + smi_buf.virt = bios_buffer + 8; + smi_buf.size = remap_size - 8; + max_smi_data_buf_size = smi_buf.size; + wsmt_enabled = true; + dev_info(&dcdbas_pdev->dev, + "WSMT found, using firmware-provided SMI buffer.\n"); + return 1; +} + +/** + * dcdbas_reboot_notify: handle reboot notification for host control + */ +static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code, + void *unused) +{ + switch (code) { + case SYS_DOWN: + case SYS_HALT: + case SYS_POWER_OFF: + if (host_control_on_shutdown) { + /* firmware is going to perform host control action */ + printk(KERN_WARNING "Please wait for shutdown " + "action to complete...\n"); + dcdbas_host_control(); + } + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block dcdbas_reboot_nb = { + .notifier_call = dcdbas_reboot_notify, + .next = NULL, + .priority = INT_MIN +}; + +static DCDBAS_BIN_ATTR_RW(smi_data); + +static struct bin_attribute *dcdbas_bin_attrs[] = { + &bin_attr_smi_data, + NULL +}; + +static DCDBAS_DEV_ATTR_RW(smi_data_buf_size); +static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr); +static DCDBAS_DEV_ATTR_WO(smi_request); +static DCDBAS_DEV_ATTR_RW(host_control_action); +static DCDBAS_DEV_ATTR_RW(host_control_smi_type); +static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown); + +static struct attribute *dcdbas_dev_attrs[] = { + &dev_attr_smi_data_buf_size.attr, + &dev_attr_smi_data_buf_phys_addr.attr, + &dev_attr_smi_request.attr, + &dev_attr_host_control_action.attr, + &dev_attr_host_control_smi_type.attr, + &dev_attr_host_control_on_shutdown.attr, + NULL +}; + +static const struct attribute_group dcdbas_attr_group = { + .attrs = dcdbas_dev_attrs, + .bin_attrs = dcdbas_bin_attrs, +}; + +static int dcdbas_probe(struct platform_device *dev) +{ + int error; + + host_control_action = HC_ACTION_NONE; + host_control_smi_type = HC_SMITYPE_NONE; + + dcdbas_pdev = dev; + + /* Check if ACPI WSMT table specifies protected SMI buffer address */ + error = dcdbas_check_wsmt(); + if (error < 0) + return error; + + /* + * BIOS SMI calls require buffer addresses be in 32-bit address space. + * This is done by setting the DMA mask below. + */ + error = dma_set_coherent_mask(&dcdbas_pdev->dev, DMA_BIT_MASK(32)); + if (error) + return error; + + error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group); + if (error) + return error; + + register_reboot_notifier(&dcdbas_reboot_nb); + + dev_info(&dev->dev, "%s (version %s)\n", + DRIVER_DESCRIPTION, DRIVER_VERSION); + + return 0; +} + +static int dcdbas_remove(struct platform_device *dev) +{ + unregister_reboot_notifier(&dcdbas_reboot_nb); + sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group); + + return 0; +} + +static struct platform_driver dcdbas_driver = { + .driver = { + .name = DRIVER_NAME, + }, + .probe = dcdbas_probe, + .remove = dcdbas_remove, +}; + +static const struct platform_device_info dcdbas_dev_info __initconst = { + .name = DRIVER_NAME, + .id = PLATFORM_DEVID_NONE, + .dma_mask = DMA_BIT_MASK(32), +}; + +static struct platform_device *dcdbas_pdev_reg; + +/** + * dcdbas_init: initialize driver + */ +static int __init dcdbas_init(void) +{ + int error; + + error = platform_driver_register(&dcdbas_driver); + if (error) + return error; + + dcdbas_pdev_reg = platform_device_register_full(&dcdbas_dev_info); + if (IS_ERR(dcdbas_pdev_reg)) { + error = PTR_ERR(dcdbas_pdev_reg); + goto err_unregister_driver; + } + + return 0; + + err_unregister_driver: + platform_driver_unregister(&dcdbas_driver); + return error; +} + +/** + * dcdbas_exit: perform driver cleanup + */ +static void __exit dcdbas_exit(void) +{ + /* + * make sure functions that use dcdbas_pdev are called + * before platform_device_unregister + */ + unregister_reboot_notifier(&dcdbas_reboot_nb); + + /* + * We have to free the buffer here instead of dcdbas_remove + * because only in module exit function we can be sure that + * all sysfs attributes belonging to this module have been + * released. + */ + if (dcdbas_pdev) + smi_data_buf_free(); + if (bios_buffer) + memunmap(bios_buffer); + platform_device_unregister(dcdbas_pdev_reg); + platform_driver_unregister(&dcdbas_driver); +} + +subsys_initcall_sync(dcdbas_init); +module_exit(dcdbas_exit); + +MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")"); +MODULE_VERSION(DRIVER_VERSION); +MODULE_AUTHOR("Dell Inc."); +MODULE_LICENSE("GPL"); +/* Any System or BIOS claiming to be by Dell */ +MODULE_ALIAS("dmi:*:[bs]vnD[Ee][Ll][Ll]*:*"); -- cgit v1.2.3