| /* SPDX-License-Identifier: GPL-2.0-only */ |
| |
| #include <device/mmio.h> |
| #include <device/device.h> |
| #include <device/pci.h> |
| #include <device/pci_ops.h> |
| #include <console/console.h> |
| #include <device/pci_ids.h> |
| #include <string.h> |
| #include <delay.h> |
| #include <halt.h> |
| #include <timer.h> |
| |
| #include "me.h" |
| #include "pch.h" |
| |
| #include <vendorcode/google/chromeos/chromeos.h> |
| |
| /* Path that the BIOS should take based on ME state */ |
| static const char *const me_bios_path_values[] = { |
| [ME_NORMAL_BIOS_PATH] = "Normal", |
| [ME_S3WAKE_BIOS_PATH] = "S3 Wake", |
| [ME_ERROR_BIOS_PATH] = "Error", |
| [ME_RECOVERY_BIOS_PATH] = "Recovery", |
| [ME_DISABLE_BIOS_PATH] = "Disable", |
| [ME_FIRMWARE_UPDATE_BIOS_PATH] = "Firmware Update", |
| }; |
| |
| const char *const me_get_bios_path_string(int path) |
| { |
| return me_bios_path_values[path]; |
| } |
| |
| /* MMIO base address for MEI interface */ |
| static u32 *mei_base_address; |
| |
| static void mei_dump(void *ptr, int dword, int offset, const char *type) |
| { |
| struct mei_csr *csr; |
| |
| if (!CONFIG(DEBUG_INTEL_ME)) |
| return; |
| |
| printk(BIOS_SPEW, "%-9s[%02x] : ", type, offset); |
| |
| switch (offset) { |
| case MEI_H_CSR: |
| case MEI_ME_CSR_HA: |
| csr = ptr; |
| if (!csr) { |
| printk(BIOS_SPEW, "ERROR: 0x%08x\n", dword); |
| break; |
| } |
| printk(BIOS_SPEW, "cbd=%u cbrp=%02u cbwp=%02u ready=%u " |
| "reset=%u ig=%u is=%u ie=%u\n", csr->buffer_depth, |
| csr->buffer_read_ptr, csr->buffer_write_ptr, |
| csr->ready, csr->reset, csr->interrupt_generate, |
| csr->interrupt_status, csr->interrupt_enable); |
| break; |
| case MEI_ME_CB_RW: |
| case MEI_H_CB_WW: |
| printk(BIOS_SPEW, "CB: 0x%08x\n", dword); |
| break; |
| default: |
| printk(BIOS_SPEW, "0x%08x\n", offset); |
| break; |
| } |
| } |
| |
| /* |
| * ME/MEI access helpers using memcpy to avoid aliasing. |
| */ |
| |
| void mei_read_dword_ptr(void *ptr, int offset) |
| { |
| u32 dword = read32(mei_base_address + (offset / sizeof(u32))); |
| memcpy(ptr, &dword, sizeof(dword)); |
| mei_dump(ptr, dword, offset, "READ"); |
| } |
| |
| void mei_write_dword_ptr(void *ptr, int offset) |
| { |
| u32 dword = 0; |
| memcpy(&dword, ptr, sizeof(dword)); |
| write32(mei_base_address + (offset / sizeof(u32)), dword); |
| mei_dump(ptr, dword, offset, "WRITE"); |
| } |
| |
| void read_host_csr(struct mei_csr *csr) |
| { |
| mei_read_dword_ptr(csr, MEI_H_CSR); |
| } |
| |
| void write_host_csr(struct mei_csr *csr) |
| { |
| mei_write_dword_ptr(csr, MEI_H_CSR); |
| } |
| |
| void read_me_csr(struct mei_csr *csr) |
| { |
| mei_read_dword_ptr(csr, MEI_ME_CSR_HA); |
| } |
| |
| void write_cb(u32 dword) |
| { |
| write32(mei_base_address + (MEI_H_CB_WW / sizeof(u32)), dword); |
| mei_dump(NULL, dword, MEI_H_CB_WW, "WRITE"); |
| } |
| |
| u32 read_cb(void) |
| { |
| u32 dword = read32(mei_base_address + (MEI_ME_CB_RW / sizeof(u32))); |
| mei_dump(NULL, dword, MEI_ME_CB_RW, "READ"); |
| return dword; |
| } |
| |
| /* Wait for ME ready bit to be asserted */ |
| static int mei_wait_for_me_ready(void) |
| { |
| struct mei_csr me; |
| unsigned int try = ME_RETRY; |
| |
| while (try--) { |
| read_me_csr(&me); |
| if (me.ready) |
| return 0; |
| udelay(ME_DELAY); |
| } |
| |
| printk(BIOS_ERR, "ME: failed to become ready\n"); |
| return -1; |
| } |
| |
| static void mei_reset(void) |
| { |
| struct mei_csr host; |
| |
| if (mei_wait_for_me_ready() < 0) |
| return; |
| |
| /* Reset host and ME circular buffers for next message */ |
| read_host_csr(&host); |
| host.reset = 1; |
| host.interrupt_generate = 1; |
| write_host_csr(&host); |
| |
| if (mei_wait_for_me_ready() < 0) |
| return; |
| |
| /* Re-init and indicate host is ready */ |
| read_host_csr(&host); |
| host.interrupt_generate = 1; |
| host.ready = 1; |
| host.reset = 0; |
| write_host_csr(&host); |
| } |
| |
| static int mei_send_msg(struct mei_header *mei, struct mkhi_header *mkhi, void *req_data) |
| { |
| struct mei_csr host; |
| unsigned int ndata, n; |
| u32 *data; |
| |
| /* Number of dwords to write, ignoring MKHI */ |
| ndata = mei->length >> 2; |
| |
| /* Pad non-dword aligned request message length */ |
| if (mei->length & 3) |
| ndata++; |
| |
| if (!ndata) { |
| printk(BIOS_DEBUG, "ME: request does not include MKHI\n"); |
| return -1; |
| } |
| ndata++; /* Add MEI header */ |
| |
| /* |
| * Make sure there is still room left in the circular buffer. |
| * Reset the buffer pointers if the requested message will not fit. |
| */ |
| read_host_csr(&host); |
| if ((host.buffer_depth - host.buffer_write_ptr) < ndata) { |
| printk(BIOS_ERR, "ME: circular buffer full, resetting...\n"); |
| mei_reset(); |
| read_host_csr(&host); |
| } |
| |
| /* |
| * This implementation does not handle splitting large messages |
| * across multiple transactions. Ensure the requested length |
| * will fit in the available circular buffer depth. |
| */ |
| if ((host.buffer_depth - host.buffer_write_ptr) < ndata) { |
| printk(BIOS_ERR, "ME: message (%u) too large for buffer (%u)\n", |
| ndata + 2, host.buffer_depth); |
| return -1; |
| } |
| |
| /* Write MEI header */ |
| mei_write_dword_ptr(mei, MEI_H_CB_WW); |
| ndata--; |
| |
| /* Write MKHI header */ |
| mei_write_dword_ptr(mkhi, MEI_H_CB_WW); |
| ndata--; |
| |
| /* Write message data */ |
| data = req_data; |
| for (n = 0; n < ndata; ++n) |
| write_cb(*data++); |
| |
| /* Generate interrupt to the ME */ |
| read_host_csr(&host); |
| host.interrupt_generate = 1; |
| write_host_csr(&host); |
| |
| /* Make sure ME is ready after sending request data */ |
| return mei_wait_for_me_ready(); |
| } |
| |
| static int mei_recv_msg(struct mkhi_header *mkhi, void *rsp_data, int rsp_bytes) |
| { |
| struct mei_header mei_rsp; |
| struct mkhi_header mkhi_rsp; |
| struct mei_csr me, host; |
| unsigned int ndata, n; |
| unsigned int expected; |
| u32 *data; |
| |
| /* Total number of dwords to read from circular buffer */ |
| expected = (rsp_bytes + sizeof(mei_rsp) + sizeof(mkhi_rsp)) >> 2; |
| if (rsp_bytes & 3) |
| expected++; |
| |
| /* |
| * The interrupt status bit does not appear to indicate that the |
| * message has actually been received. Instead we wait until the |
| * expected number of dwords are present in the circular buffer. |
| */ |
| for (n = ME_RETRY; n; --n) { |
| read_me_csr(&me); |
| if ((me.buffer_write_ptr - me.buffer_read_ptr) >= expected) |
| break; |
| udelay(ME_DELAY); |
| } |
| |
| if (!n) { |
| printk(BIOS_ERR, "ME: timeout waiting for data: expected %u, available %u\n", |
| expected, me.buffer_write_ptr - me.buffer_read_ptr); |
| return -1; |
| } |
| |
| /* Read and verify MEI response header from the ME */ |
| mei_read_dword_ptr(&mei_rsp, MEI_ME_CB_RW); |
| if (!mei_rsp.is_complete) { |
| printk(BIOS_ERR, "ME: response is not complete\n"); |
| return -1; |
| } |
| |
| /* Handle non-dword responses and expect at least MKHI header */ |
| ndata = mei_rsp.length >> 2; |
| if (mei_rsp.length & 3) |
| ndata++; |
| |
| if (ndata != (expected - 1)) { |
| printk(BIOS_ERR, "ME: response is missing data %d != %d\n", |
| ndata, (expected - 1)); |
| return -1; |
| } |
| |
| /* Read and verify MKHI response header from the ME */ |
| mei_read_dword_ptr(&mkhi_rsp, MEI_ME_CB_RW); |
| if (!mkhi_rsp.is_response || |
| mkhi->group_id != mkhi_rsp.group_id || |
| mkhi->command != mkhi_rsp.command) { |
| printk(BIOS_ERR, "ME: invalid response, group %u ?= %u, " |
| "command %u ?= %u, is_response %u\n", mkhi->group_id, |
| mkhi_rsp.group_id, mkhi->command, mkhi_rsp.command, |
| mkhi_rsp.is_response); |
| return -1; |
| } |
| ndata--; /* MKHI header has been read */ |
| |
| /* Make sure caller passed a buffer with enough space */ |
| if (ndata != (rsp_bytes >> 2)) { |
| printk(BIOS_ERR, "ME: not enough room in response buffer: %u != %u\n", |
| ndata, rsp_bytes >> 2); |
| return -1; |
| } |
| |
| /* Read response data from the circular buffer */ |
| data = rsp_data; |
| for (n = 0; n < ndata; ++n) |
| *data++ = read_cb(); |
| |
| /* Tell the ME that we have consumed the response */ |
| read_host_csr(&host); |
| host.interrupt_status = 1; |
| host.interrupt_generate = 1; |
| write_host_csr(&host); |
| |
| return mei_wait_for_me_ready(); |
| } |
| |
| int mei_sendrecv(struct mei_header *mei, struct mkhi_header *mkhi, |
| void *req_data, void *rsp_data, int rsp_bytes) |
| { |
| if (mei_send_msg(mei, mkhi, req_data) < 0) |
| return -1; |
| if (mei_recv_msg(mkhi, rsp_data, rsp_bytes) < 0) |
| return -1; |
| return 0; |
| } |
| |
| #ifdef __SIMPLE_DEVICE__ |
| |
| void update_mei_base_address(void) |
| { |
| uint32_t reg32 = pci_read_config32(PCH_ME_DEV, PCI_BASE_ADDRESS_0) & ~0xf; |
| mei_base_address = (u32 *)(uintptr_t)reg32; |
| } |
| |
| bool is_mei_base_address_valid(void) |
| { |
| return mei_base_address && mei_base_address != (u32 *)0xfffffff0; |
| } |
| |
| #else |
| |
| /* Prepare ME for MEI messages */ |
| int intel_mei_setup(struct device *dev) |
| { |
| struct resource *res; |
| struct mei_csr host; |
| |
| /* Find the MMIO base for the ME interface */ |
| res = probe_resource(dev, PCI_BASE_ADDRESS_0); |
| if (!res || res->base == 0 || res->size == 0) { |
| printk(BIOS_DEBUG, "ME: MEI resource not present!\n"); |
| return -1; |
| } |
| mei_base_address = (u32 *)(uintptr_t)res->base; |
| |
| /* Ensure Memory and Bus Master bits are set */ |
| pci_or_config16(dev, PCI_COMMAND, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY); |
| |
| /* Clean up status for next message */ |
| read_host_csr(&host); |
| host.interrupt_generate = 1; |
| host.ready = 1; |
| host.reset = 0; |
| write_host_csr(&host); |
| |
| return 0; |
| } |
| |
| /* Read the Extend register hash of ME firmware */ |
| int intel_me_extend_valid(struct device *dev) |
| { |
| union me_heres status; |
| u32 extend[8] = {0}; |
| int i, count = 0; |
| |
| status.raw = pci_read_config32(dev, PCI_ME_HERES); |
| if (!status.extend_feature_present) { |
| printk(BIOS_ERR, "ME: Extend Feature not present\n"); |
| return -1; |
| } |
| |
| if (!status.extend_reg_valid) { |
| printk(BIOS_ERR, "ME: Extend Register not valid\n"); |
| return -1; |
| } |
| |
| switch (status.extend_reg_algorithm) { |
| case PCI_ME_EXT_SHA1: |
| count = 5; |
| printk(BIOS_DEBUG, "ME: Extend SHA-1: "); |
| break; |
| case PCI_ME_EXT_SHA256: |
| count = 8; |
| printk(BIOS_DEBUG, "ME: Extend SHA-256: "); |
| break; |
| default: |
| printk(BIOS_ERR, "ME: Extend Algorithm %d unknown\n", |
| status.extend_reg_algorithm); |
| return -1; |
| } |
| |
| for (i = 0; i < count; ++i) { |
| extend[i] = pci_read_config32(dev, PCI_ME_HER(i)); |
| printk(BIOS_DEBUG, "%08x", extend[i]); |
| } |
| printk(BIOS_DEBUG, "\n"); |
| |
| /* Save hash in NVS for the OS to verify */ |
| if (CONFIG(CHROMEOS_NVS)) |
| chromeos_set_me_hash(extend, count); |
| |
| return 0; |
| } |
| |
| /* Hide the ME virtual PCI devices */ |
| void intel_me_hide(struct device *dev) |
| { |
| dev->enabled = 0; |
| pch_enable(dev); |
| } |
| |
| bool enter_soft_temp_disable(void) |
| { |
| /* The binary sequence for the disable command was found by PT in some vendor BIOS */ |
| struct me_disable message = { |
| .rule_id = MKHI_DISABLE_RULE_ID, |
| .data = 0x01, |
| }; |
| struct mkhi_header mkhi = { |
| .group_id = MKHI_GROUP_ID_FWCAPS, |
| .command = MKHI_FWCAPS_SET_RULE, |
| }; |
| struct mei_header mei = { |
| .is_complete = 1, |
| .length = sizeof(mkhi) + sizeof(message), |
| .host_address = MEI_HOST_ADDRESS, |
| .client_address = MEI_ADDRESS_MKHI, |
| }; |
| u32 resp; |
| |
| if (mei_sendrecv(&mei, &mkhi, &message, &resp, sizeof(resp)) < 0 |
| || resp != MKHI_DISABLE_RULE_ID) { |
| printk(BIOS_WARNING, "ME: disable command failed\n"); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| void enter_soft_temp_disable_wait(void) |
| { |
| /* |
| * TODO: Find smarter way to determine when we're ready to reboot. |
| * |
| * There has to be some bit in some register, or something, that indicates that ME has |
| * finished doing its thing and we're ready to reboot. |
| * |
| * It was not found yet, though, and waiting for a response after the disable command is |
| * not enough. If we reboot too early, ME will not be disabled on next boot. For now, |
| * let's just wait for 1 second here. |
| */ |
| mdelay(1000); |
| } |
| |
| void exit_soft_temp_disable(struct device *dev) |
| { |
| /* To bring ME out of Soft Temporary Disable Mode, host writes 0x20000000 to H_GS */ |
| pci_write_config32(dev, PCI_ME_H_GS, 0x2 << 28); |
| } |
| |
| void exit_soft_temp_disable_wait(struct device *dev) |
| { |
| union me_hfs hfs; |
| struct stopwatch sw; |
| |
| stopwatch_init_msecs_expire(&sw, ME_ENABLE_TIMEOUT); |
| |
| /** |
| * Wait for fw_init_complete. Check every 50 ms, give up after 20 sec. |
| * This is what vendor BIOS does. Usually it takes 1.5 seconds or so. |
| */ |
| do { |
| mdelay(50); |
| hfs.raw = pci_read_config32(dev, PCI_ME_HFS); |
| if (hfs.fw_init_complete) |
| break; |
| } while (!stopwatch_expired(&sw)); |
| |
| if (!hfs.fw_init_complete) |
| printk(BIOS_ERR, "ME: giving up on waiting for fw_init_complete\n"); |
| else |
| printk(BIOS_NOTICE, "ME: took %lldms to complete initialization\n", |
| stopwatch_duration_msecs(&sw)); |
| } |
| |
| #endif |