/* * * Intel Management Engine Interface (Intel MEI) Linux driver * Copyright (c) 2003-2012, Intel Corporation. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * */ #include <linux/pci.h> #include <linux/kthread.h> #include <linux/interrupt.h> #include "mei_dev.h" #include "hbm.h" #include "hw-me.h" #include "hw-me-regs.h" /** * mei_me_reg_read - Reads 32bit data from the mei device * * @hw: the me hardware structure * @offset: offset from which to read the data * * Return: register value (u32) */ static inline u32 mei_me_reg_read(const struct mei_me_hw *hw, unsigned long offset) { return ioread32(hw->mem_addr + offset); } /** * mei_me_reg_write - Writes 32bit data to the mei device * * @hw: the me hardware structure * @offset: offset from which to write the data * @value: register value to write (u32) */ static inline void mei_me_reg_write(const struct mei_me_hw *hw, unsigned long offset, u32 value) { iowrite32(value, hw->mem_addr + offset); } /** * mei_me_mecbrw_read - Reads 32bit data from ME circular buffer * read window register * * @dev: the device structure * * Return: ME_CB_RW register value (u32) */ static u32 mei_me_mecbrw_read(const struct mei_device *dev) { return mei_me_reg_read(to_me_hw(dev), ME_CB_RW); } /** * mei_me_mecsr_read - Reads 32bit data from the ME CSR * * @hw: the me hardware structure * * Return: ME_CSR_HA register value (u32) */ static inline u32 mei_me_mecsr_read(const struct mei_me_hw *hw) { return mei_me_reg_read(hw, ME_CSR_HA); } /** * mei_hcsr_read - Reads 32bit data from the host CSR * * @hw: the me hardware structure * * Return: H_CSR register value (u32) */ static inline u32 mei_hcsr_read(const struct mei_me_hw *hw) { return mei_me_reg_read(hw, H_CSR); } /** * mei_hcsr_set - writes H_CSR register to the mei device, * and ignores the H_IS bit for it is write-one-to-zero. * * @hw: the me hardware structure * @hcsr: new register value */ static inline void mei_hcsr_set(struct mei_me_hw *hw, u32 hcsr) { hcsr &= ~H_IS; mei_me_reg_write(hw, H_CSR, hcsr); } /** * mei_me_fw_status - read fw status register from pci config space * * @dev: mei device * @fw_status: fw status register values * * Return: 0 on success, error otherwise */ static int mei_me_fw_status(struct mei_device *dev, struct mei_fw_status *fw_status) { struct pci_dev *pdev = to_pci_dev(dev->dev); struct mei_me_hw *hw = to_me_hw(dev); const struct mei_fw_status *fw_src = &hw->cfg->fw_status; int ret; int i; if (!fw_status) return -EINVAL; fw_status->count = fw_src->count; for (i = 0; i < fw_src->count && i < MEI_FW_STATUS_MAX; i++) { ret = pci_read_config_dword(pdev, fw_src->status[i], &fw_status->status[i]); if (ret) return ret; } return 0; } /** * mei_me_hw_config - configure hw dependent settings * * @dev: mei device */ static void mei_me_hw_config(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(to_me_hw(dev)); /* Doesn't change in runtime */ dev->hbuf_depth = (hcsr & H_CBD) >> 24; hw->pg_state = MEI_PG_OFF; } /** * mei_me_pg_state - translate internal pg state * to the mei power gating state * * @dev: mei device * * Return: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise */ static inline enum mei_pg_state mei_me_pg_state(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); return hw->pg_state; } /** * mei_me_intr_clear - clear and stop interrupts * * @dev: the device structure */ static void mei_me_intr_clear(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(hw); if ((hcsr & H_IS) == H_IS) mei_me_reg_write(hw, H_CSR, hcsr); } /** * mei_me_intr_enable - enables mei device interrupts * * @dev: the device structure */ static void mei_me_intr_enable(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(hw); hcsr |= H_IE; mei_hcsr_set(hw, hcsr); } /** * mei_me_intr_disable - disables mei device interrupts * * @dev: the device structure */ static void mei_me_intr_disable(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(hw); hcsr &= ~H_IE; mei_hcsr_set(hw, hcsr); } /** * mei_me_hw_reset_release - release device from the reset * * @dev: the device structure */ static void mei_me_hw_reset_release(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(hw); hcsr |= H_IG; hcsr &= ~H_RST; mei_hcsr_set(hw, hcsr); /* complete this write before we set host ready on another CPU */ mmiowb(); } /** * mei_me_hw_reset - resets fw via mei csr register. * * @dev: the device structure * @intr_enable: if interrupt should be enabled after reset. * * Return: always 0 */ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable) { struct mei_me_hw *hw = to_me_hw(dev); u32 hcsr = mei_hcsr_read(hw); hcsr |= H_RST | H_IG | H_IS; if (intr_enable) hcsr |= H_IE; else hcsr &= ~H_IE; dev->recvd_hw_ready = false; mei_me_reg_write(hw, H_CSR, hcsr); /* * Host reads the H_CSR once to ensure that the * posted write to H_CSR completes. */ hcsr = mei_hcsr_read(hw); if ((hcsr & H_RST) == 0) dev_warn(dev->dev, "H_RST is not set = 0x%08X", hcsr); if ((hcsr & H_RDY) == H_RDY) dev_warn(dev->dev, "H_RDY is not cleared 0x%08X", hcsr); if (intr_enable == false) mei_me_hw_reset_release(dev); return 0; } /** * mei_me_host_set_ready - enable device * * @dev: mei device */ static void mei_me_host_set_ready(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); hw->host_hw_state = mei_hcsr_read(hw); hw->host_hw_state |= H_IE | H_IG | H_RDY; mei_hcsr_set(hw, hw->host_hw_state); } /** * mei_me_host_is_ready - check whether the host has turned ready * * @dev: mei device * Return: bool */ static bool mei_me_host_is_ready(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); hw->host_hw_state = mei_hcsr_read(hw); return (hw->host_hw_state & H_RDY) == H_RDY; } /** * mei_me_hw_is_ready - check whether the me(hw) has turned ready * * @dev: mei device * Return: bool */ static bool mei_me_hw_is_ready(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); hw->me_hw_state = mei_me_mecsr_read(hw); return (hw->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA; } /** * mei_me_hw_ready_wait - wait until the me(hw) has turned ready * or timeout is reached * * @dev: mei device * Return: 0 on success, error otherwise */ static int mei_me_hw_ready_wait(struct mei_device *dev) { mutex_unlock(&dev->device_lock); wait_event_timeout(dev->wait_hw_ready, dev->recvd_hw_ready, mei_secs_to_jiffies(MEI_HW_READY_TIMEOUT)); mutex_lock(&dev->device_lock); if (!dev->recvd_hw_ready) { dev_err(dev->dev, "wait hw ready failed\n"); return -ETIME; } dev->recvd_hw_ready = false; return 0; } /** * mei_me_hw_start - hw start routine * * @dev: mei device * Return: 0 on success, error otherwise */ static int mei_me_hw_start(struct mei_device *dev) { int ret = mei_me_hw_ready_wait(dev); if (ret) return ret; dev_dbg(dev->dev, "hw is ready\n"); mei_me_host_set_ready(dev); return ret; } /** * mei_hbuf_filled_slots - gets number of device filled buffer slots * * @dev: the device structure * * Return: number of filled slots */ static unsigned char mei_hbuf_filled_slots(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); char read_ptr, write_ptr; hw->host_hw_state = mei_hcsr_read(hw); read_ptr = (char) ((hw->host_hw_state & H_CBRP) >> 8); write_ptr = (char) ((hw->host_hw_state & H_CBWP) >> 16); return (unsigned char) (write_ptr - read_ptr); } /** * mei_me_hbuf_is_empty - checks if host buffer is empty. * * @dev: the device structure * * Return: true if empty, false - otherwise. */ static bool mei_me_hbuf_is_empty(struct mei_device *dev) { return mei_hbuf_filled_slots(dev) == 0; } /** * mei_me_hbuf_empty_slots - counts write empty slots. * * @dev: the device structure * * Return: -EOVERFLOW if overflow, otherwise empty slots count */ static int mei_me_hbuf_empty_slots(struct mei_device *dev) { unsigned char filled_slots, empty_slots; filled_slots = mei_hbuf_filled_slots(dev); empty_slots = dev->hbuf_depth - filled_slots; /* check for overflow */ if (filled_slots > dev->hbuf_depth) return -EOVERFLOW; return empty_slots; } /** * mei_me_hbuf_max_len - returns size of hw buffer. * * @dev: the device structure * * Return: size of hw buffer in bytes */ static size_t mei_me_hbuf_max_len(const struct mei_device *dev) { return dev->hbuf_depth * sizeof(u32) - sizeof(struct mei_msg_hdr); } /** * mei_me_write_message - writes a message to mei device. * * @dev: the device structure * @header: mei HECI header of message * @buf: message payload will be written * * Return: -EIO if write has failed */ static int mei_me_write_message(struct mei_device *dev, struct mei_msg_hdr *header, unsigned char *buf) { struct mei_me_hw *hw = to_me_hw(dev); unsigned long rem; unsigned long length = header->length; u32 *reg_buf = (u32 *)buf; u32 hcsr; u32 dw_cnt; int i; int empty_slots; dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(header)); empty_slots = mei_hbuf_empty_slots(dev); dev_dbg(dev->dev, "empty slots = %hu.\n", empty_slots); dw_cnt = mei_data2slots(length); if (empty_slots < 0 || dw_cnt > empty_slots) return -EMSGSIZE; mei_me_reg_write(hw, H_CB_WW, *((u32 *) header)); for (i = 0; i < length / 4; i++) mei_me_reg_write(hw, H_CB_WW, reg_buf[i]); rem = length & 0x3; if (rem > 0) { u32 reg = 0; memcpy(®, &buf[length - rem], rem); mei_me_reg_write(hw, H_CB_WW, reg); } hcsr = mei_hcsr_read(hw) | H_IG; mei_hcsr_set(hw, hcsr); if (!mei_me_hw_is_ready(dev)) return -EIO; return 0; } /** * mei_me_count_full_read_slots - counts read full slots. * * @dev: the device structure * * Return: -EOVERFLOW if overflow, otherwise filled slots count */ static int mei_me_count_full_read_slots(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); char read_ptr, write_ptr; unsigned char buffer_depth, filled_slots; hw->me_hw_state = mei_me_mecsr_read(hw); buffer_depth = (unsigned char)((hw->me_hw_state & ME_CBD_HRA) >> 24); read_ptr = (char) ((hw->me_hw_state & ME_CBRP_HRA) >> 8); write_ptr = (char) ((hw->me_hw_state & ME_CBWP_HRA) >> 16); filled_slots = (unsigned char) (write_ptr - read_ptr); /* check for overflow */ if (filled_slots > buffer_depth) return -EOVERFLOW; dev_dbg(dev->dev, "filled_slots =%08x\n", filled_slots); return (int)filled_slots; } /** * mei_me_read_slots - reads a message from mei device. * * @dev: the device structure * @buffer: message buffer will be written * @buffer_length: message size will be read * * Return: always 0 */ static int mei_me_read_slots(struct mei_device *dev, unsigned char *buffer, unsigned long buffer_length) { struct mei_me_hw *hw = to_me_hw(dev); u32 *reg_buf = (u32 *)buffer; u32 hcsr; for (; buffer_length >= sizeof(u32); buffer_length -= sizeof(u32)) *reg_buf++ = mei_me_mecbrw_read(dev); if (buffer_length > 0) { u32 reg = mei_me_mecbrw_read(dev); memcpy(reg_buf, ®, buffer_length); } hcsr = mei_hcsr_read(hw) | H_IG; mei_hcsr_set(hw, hcsr); return 0; } /** * mei_me_pg_enter - write pg enter register * * @dev: the device structure */ static void mei_me_pg_enter(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 reg = mei_me_reg_read(hw, H_HPG_CSR); reg |= H_HPG_CSR_PGI; mei_me_reg_write(hw, H_HPG_CSR, reg); } /** * mei_me_pg_exit - write pg exit register * * @dev: the device structure */ static void mei_me_pg_exit(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 reg = mei_me_reg_read(hw, H_HPG_CSR); WARN(!(reg & H_HPG_CSR_PGI), "PGI is not set\n"); reg |= H_HPG_CSR_PGIHEXR; mei_me_reg_write(hw, H_HPG_CSR, reg); } /** * mei_me_pg_set_sync - perform pg entry procedure * * @dev: the device structure * * Return: 0 on success an error code otherwise */ int mei_me_pg_set_sync(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT); int ret; dev->pg_event = MEI_PG_EVENT_WAIT; ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_ENTRY_REQ_CMD); if (ret) return ret; mutex_unlock(&dev->device_lock); wait_event_timeout(dev->wait_pg, dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout); mutex_lock(&dev->device_lock); if (dev->pg_event == MEI_PG_EVENT_RECEIVED) { mei_me_pg_enter(dev); ret = 0; } else { ret = -ETIME; } dev->pg_event = MEI_PG_EVENT_IDLE; hw->pg_state = MEI_PG_ON; return ret; } /** * mei_me_pg_unset_sync - perform pg exit procedure * * @dev: the device structure * * Return: 0 on success an error code otherwise */ int mei_me_pg_unset_sync(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); unsigned long timeout = mei_secs_to_jiffies(MEI_PGI_TIMEOUT); int ret; if (dev->pg_event == MEI_PG_EVENT_RECEIVED) goto reply; dev->pg_event = MEI_PG_EVENT_WAIT; mei_me_pg_exit(dev); mutex_unlock(&dev->device_lock); wait_event_timeout(dev->wait_pg, dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout); mutex_lock(&dev->device_lock); reply: if (dev->pg_event == MEI_PG_EVENT_RECEIVED) ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD); else ret = -ETIME; dev->pg_event = MEI_PG_EVENT_IDLE; hw->pg_state = MEI_PG_OFF; return ret; } /** * mei_me_pg_is_enabled - detect if PG is supported by HW * * @dev: the device structure * * Return: true is pg supported, false otherwise */ static bool mei_me_pg_is_enabled(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); u32 reg = mei_me_reg_read(hw, ME_CSR_HA); if ((reg & ME_PGIC_HRA) == 0) goto notsupported; if (!dev->hbm_f_pg_supported) goto notsupported; return true; notsupported: dev_dbg(dev->dev, "pg: not supported: HGP = %d hbm version %d.%d ?= %d.%d\n", !!(reg & ME_PGIC_HRA), dev->version.major_version, dev->version.minor_version, HBM_MAJOR_VERSION_PGI, HBM_MINOR_VERSION_PGI); return false; } /** * mei_me_irq_quick_handler - The ISR of the MEI device * * @irq: The irq number * @dev_id: pointer to the device structure * * Return: irqreturn_t */ irqreturn_t mei_me_irq_quick_handler(int irq, void *dev_id) { struct mei_device *dev = (struct mei_device *) dev_id; struct mei_me_hw *hw = to_me_hw(dev); u32 csr_reg = mei_hcsr_read(hw); if ((csr_reg & H_IS) != H_IS) return IRQ_NONE; /* clear H_IS bit in H_CSR */ mei_me_reg_write(hw, H_CSR, csr_reg); return IRQ_WAKE_THREAD; } /** * mei_me_irq_thread_handler - function called after ISR to handle the interrupt * processing. * * @irq: The irq number * @dev_id: pointer to the device structure * * Return: irqreturn_t * */ irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id) { struct mei_device *dev = (struct mei_device *) dev_id; struct mei_cl_cb complete_list; s32 slots; int rets = 0; dev_dbg(dev->dev, "function called after ISR to handle the interrupt processing.\n"); /* initialize our complete list */ mutex_lock(&dev->device_lock); mei_io_list_init(&complete_list); /* Ack the interrupt here * In case of MSI we don't go through the quick handler */ if (pci_dev_msi_enabled(to_pci_dev(dev->dev))) mei_clear_interrupts(dev); /* check if ME wants a reset */ if (!mei_hw_is_ready(dev) && dev->dev_state != MEI_DEV_RESETTING) { dev_warn(dev->dev, "FW not ready: resetting.\n"); schedule_work(&dev->reset_work); goto end; } /* check if we need to start the dev */ if (!mei_host_is_ready(dev)) { if (mei_hw_is_ready(dev)) { mei_me_hw_reset_release(dev); dev_dbg(dev->dev, "we need to start the dev.\n"); dev->recvd_hw_ready = true; wake_up(&dev->wait_hw_ready); } else { dev_dbg(dev->dev, "Spurious Interrupt\n"); } goto end; } /* check slots available for reading */ slots = mei_count_full_read_slots(dev); while (slots > 0) { dev_dbg(dev->dev, "slots to read = %08x\n", slots); rets = mei_irq_read_handler(dev, &complete_list, &slots); /* There is a race between ME write and interrupt delivery: * Not all data is always available immediately after the * interrupt, so try to read again on the next interrupt. */ if (rets == -ENODATA) break; if (rets && dev->dev_state != MEI_DEV_RESETTING) { dev_err(dev->dev, "mei_irq_read_handler ret = %d.\n", rets); schedule_work(&dev->reset_work); goto end; } } dev->hbuf_is_ready = mei_hbuf_is_ready(dev); /* * During PG handshake only allowed write is the replay to the * PG exit message, so block calling write function * if the pg state is not idle */ if (dev->pg_event == MEI_PG_EVENT_IDLE) { rets = mei_irq_write_handler(dev, &complete_list); dev->hbuf_is_ready = mei_hbuf_is_ready(dev); } mei_irq_compl_handler(dev, &complete_list); end: dev_dbg(dev->dev, "interrupt thread end ret = %d\n", rets); mutex_unlock(&dev->device_lock); return IRQ_HANDLED; } static const struct mei_hw_ops mei_me_hw_ops = { .fw_status = mei_me_fw_status, .pg_state = mei_me_pg_state, .host_is_ready = mei_me_host_is_ready, .hw_is_ready = mei_me_hw_is_ready, .hw_reset = mei_me_hw_reset, .hw_config = mei_me_hw_config, .hw_start = mei_me_hw_start, .pg_is_enabled = mei_me_pg_is_enabled, .intr_clear = mei_me_intr_clear, .intr_enable = mei_me_intr_enable, .intr_disable = mei_me_intr_disable, .hbuf_free_slots = mei_me_hbuf_empty_slots, .hbuf_is_ready = mei_me_hbuf_is_empty, .hbuf_max_len = mei_me_hbuf_max_len, .write = mei_me_write_message, .rdbuf_full_slots = mei_me_count_full_read_slots, .read_hdr = mei_me_mecbrw_read, .read = mei_me_read_slots }; static bool mei_me_fw_type_nm(struct pci_dev *pdev) { u32 reg; pci_read_config_dword(pdev, PCI_CFG_HFS_2, ®); /* make sure that bit 9 (NM) is up and bit 10 (DM) is down */ return (reg & 0x600) == 0x200; } #define MEI_CFG_FW_NM \ .quirk_probe = mei_me_fw_type_nm static bool mei_me_fw_type_sps(struct pci_dev *pdev) { u32 reg; /* Read ME FW Status check for SPS Firmware */ pci_read_config_dword(pdev, PCI_CFG_HFS_1, ®); /* if bits [19:16] = 15, running SPS Firmware */ return (reg & 0xf0000) == 0xf0000; } #define MEI_CFG_FW_SPS \ .quirk_probe = mei_me_fw_type_sps #define MEI_CFG_LEGACY_HFS \ .fw_status.count = 0 #define MEI_CFG_ICH_HFS \ .fw_status.count = 1, \ .fw_status.status[0] = PCI_CFG_HFS_1 #define MEI_CFG_PCH_HFS \ .fw_status.count = 2, \ .fw_status.status[0] = PCI_CFG_HFS_1, \ .fw_status.status[1] = PCI_CFG_HFS_2 /* ICH Legacy devices */ const struct mei_cfg mei_me_legacy_cfg = { MEI_CFG_LEGACY_HFS, }; /* ICH devices */ const struct mei_cfg mei_me_ich_cfg = { MEI_CFG_ICH_HFS, }; /* PCH devices */ const struct mei_cfg mei_me_pch_cfg = { MEI_CFG_PCH_HFS, }; /* PCH Cougar Point and Patsburg with quirk for Node Manager exclusion */ const struct mei_cfg mei_me_pch_cpt_pbg_cfg = { MEI_CFG_PCH_HFS, MEI_CFG_FW_NM, }; /* PCH Lynx Point with quirk for SPS Firmware exclusion */ const struct mei_cfg mei_me_lpt_cfg = { MEI_CFG_PCH_HFS, MEI_CFG_FW_SPS, }; /** * mei_me_dev_init - allocates and initializes the mei device structure * * @pdev: The pci device structure * @cfg: per device generation config * * Return: The mei_device_device pointer on success, NULL on failure. */ struct mei_device *mei_me_dev_init(struct pci_dev *pdev, const struct mei_cfg *cfg) { struct mei_device *dev; struct mei_me_hw *hw; dev = kzalloc(sizeof(struct mei_device) + sizeof(struct mei_me_hw), GFP_KERNEL); if (!dev) return NULL; hw = to_me_hw(dev); mei_device_init(dev, &pdev->dev, &mei_me_hw_ops); hw->cfg = cfg; return dev; }