[RFC PATCH 08/14] drm/qaic: Add RAS component
From: Jeffrey Hugo
Date: Mon Aug 15 2022 - 15:34:02 EST
A QAIC device can report a number of different internal errors. The RAS
component services these reports by logging them for the sysadmin, and
collecting statistics.
Change-Id: Ib2f0731daf9a4afe05724e550c72bf32313e79bc
Signed-off-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
---
drivers/gpu/drm/qaic/qaic_ras.c | 653 ++++++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/qaic/qaic_ras.h | 11 +
2 files changed, 664 insertions(+)
create mode 100644 drivers/gpu/drm/qaic/qaic_ras.c
create mode 100644 drivers/gpu/drm/qaic/qaic_ras.h
diff --git a/drivers/gpu/drm/qaic/qaic_ras.c b/drivers/gpu/drm/qaic/qaic_ras.c
new file mode 100644
index 0000000..ab51b2d
--- /dev/null
+++ b/drivers/gpu/drm/qaic/qaic_ras.c
@@ -0,0 +1,653 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/* Copyright (c) 2020-2021, The Linux Foundation. All rights reserved. */
+/* Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. */
+
+#include <asm/byteorder.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/mhi.h>
+
+#include "qaic.h"
+#include "qaic_ras.h"
+
+#define MAGIC 0x55AA
+#define VERSION 0x1
+#define HDR_SZ 12
+#define NUM_TEMP_LVL 3
+
+enum msg_type {
+ MSG_PUSH, /* async push from device */
+ MSG_REQ, /* sync request to device */
+ MSG_RESP, /* sync response from device */
+};
+
+enum err_type {
+ CE, /* correctable error */
+ UE, /* uncorrectable error */
+ UE_NF, /* uncorrectable error that is non-fatal, expect a disruption */
+ ERR_TYPE_MAX,
+};
+
+static const char * const err_type_str[] = {
+ [CE] = "Correctable",
+ [UE] = "Uncorrectable",
+ [UE_NF] = "Uncorrectable Non-Fatal",
+};
+
+static const char * const err_class_str[] = {
+ [CE] = "Warning",
+ [UE] = "Fatal",
+ [UE_NF] = "Warning",
+};
+
+enum err_source {
+ SOC_MEM,
+ PCIE,
+ DDR,
+ SYS_BUS1,
+ SYS_BUS2,
+ NSP_MEM,
+ TSENS,
+};
+
+static const char * const err_src_str[TSENS + 1] = {
+ [SOC_MEM] = "SoC Memory",
+ [PCIE] = "PCIE",
+ [DDR] = "DDR",
+ [SYS_BUS1] = "System Bus source 1",
+ [SYS_BUS2] = "System Bus source 2",
+ [NSP_MEM] = "NSP Memory",
+ [TSENS] = "Temperature Sensors",
+};
+
+struct ras_data {
+ /* header start */
+ /* Magic number to validate the message */
+ u16 magic;
+ /* RAS version number */
+ u16 ver;
+ u32 seq_num;
+ /* RAS message type */
+ u8 type;
+ u8 id;
+ /* Size of RAS message without the header in byte */
+ u16 len;
+ /* header end */
+
+ u32 result;
+ /*
+ * Error source
+ * 0 : SoC Memory
+ * 1 : PCIE
+ * 2 : DDR
+ * 3 : System Bus source 1
+ * 4 : System Bus source 2
+ * 5 : NSP Memory
+ * 6 : Temperature Sensors
+ */
+ u32 source;
+ /*
+ * Stores the error type, there are three types of error in RAS
+ * 0 : correctable error (CE)
+ * 1 : uncorrectable error (UE)
+ * 2 : uncorrectable error that is non-fatal (UE_NF)
+ */
+ u32 err_type;
+ u32 err_threshold;
+ u32 ce_count;
+ u32 ue_count;
+ u32 intr_num;
+ /* Data specific to error source */
+ u8 syndrome[64];
+} __packed;
+
+struct soc_mem_syndrome {
+ u64 error_address[8];
+} __packed;
+
+struct nsp_mem_syndrome {
+ u32 error_address[8];
+ u8 nsp_id;
+} __packed;
+
+struct ddr_syndrome {
+ u16 instance;
+ u16 err_type;
+ u32 count;
+ u32 irq_status;
+ u32 data_31_0[2];
+ u32 data_63_32[2];
+ u32 data_95_64[2];
+ u32 data_127_96[2];
+ u16 parity_bits;
+ u16 addr_msb;
+ u32 addr_lsb;
+} __packed;
+
+struct tsens_syndrome {
+ u32 threshold_type;
+ u32 temp;
+} __packed;
+
+struct sysbus1_syndrome {
+ u8 instance;
+ u32 slave;
+ u32 err_type;
+ u16 addr[8];
+} __packed;
+
+struct sysbus2_syndrome {
+ u8 instance;
+ u8 valid;
+ u8 word_error;
+ u8 non_secure;
+ u8 opc;
+ u8 error_code;
+ u8 trans_type;
+ u8 addr_space;
+ u16 op_type;
+ u16 len;
+ u16 redirect;
+ u16 path;
+ u32 ext_id;
+ u32 lsb2;
+ u32 msb2;
+ u32 lsb3;
+ u32 msb3;
+} __packed;
+
+struct pcie_syndrome {
+ /* CE info */
+ u32 bad_tlp;
+ u32 bad_dllp;
+ u32 replay_rollover;
+ u32 replay_timeout;
+ u32 rx_err;
+ u32 internal_ce_count;
+ /* UE info */
+ u8 index;
+ u32 addr;
+ /* UE_NF info */
+ u32 fc_timeout;
+ u32 poison_tlp;
+ u32 ecrc_err;
+ u32 unsupported_req;
+ u32 completer_abort;
+ u32 completion_timeout;
+} __packed;
+
+static const char * const threshold_type_str[NUM_TEMP_LVL] = {
+ [0] = "lower",
+ [1] = "upper",
+ [2] = "critical",
+};
+
+static void ras_msg_to_cpu(struct ras_data *msg)
+{
+ struct sysbus1_syndrome *sysbus1_syndrome =
+ (struct sysbus1_syndrome *)&msg->syndrome[0];
+ struct sysbus2_syndrome *sysbus2_syndrome =
+ (struct sysbus2_syndrome *)&msg->syndrome[0];
+ struct soc_mem_syndrome *soc_syndrome =
+ (struct soc_mem_syndrome *)&msg->syndrome[0];
+ struct nsp_mem_syndrome *nsp_syndrome =
+ (struct nsp_mem_syndrome *)&msg->syndrome[0];
+ struct tsens_syndrome *tsens_syndrome =
+ (struct tsens_syndrome *)&msg->syndrome[0];
+ struct pcie_syndrome *pcie_syndrome =
+ (struct pcie_syndrome *)&msg->syndrome[0];
+ struct ddr_syndrome *ddr_syndrome =
+ (struct ddr_syndrome *)&msg->syndrome[0];
+ int i;
+
+ le16_to_cpus(&msg->magic);
+ le16_to_cpus(&msg->ver);
+ le32_to_cpus(&msg->seq_num);
+ le16_to_cpus(&msg->len);
+ le32_to_cpus(&msg->result);
+ le32_to_cpus(&msg->source);
+ le32_to_cpus(&msg->err_type);
+ le32_to_cpus(&msg->err_threshold);
+ le32_to_cpus(&msg->ce_count);
+ le32_to_cpus(&msg->ue_count);
+ le32_to_cpus(&msg->intr_num);
+
+ switch (msg->source) {
+ case SOC_MEM:
+ for (i = 0; i < 8; i++)
+ le64_to_cpus(&soc_syndrome->error_address[i]);
+ break;
+ case PCIE:
+ le32_to_cpus(&pcie_syndrome->bad_tlp);
+ le32_to_cpus(&pcie_syndrome->bad_dllp);
+ le32_to_cpus(&pcie_syndrome->replay_rollover);
+ le32_to_cpus(&pcie_syndrome->replay_timeout);
+ le32_to_cpus(&pcie_syndrome->rx_err);
+ le32_to_cpus(&pcie_syndrome->internal_ce_count);
+ le32_to_cpus(&pcie_syndrome->fc_timeout);
+ le32_to_cpus(&pcie_syndrome->poison_tlp);
+ le32_to_cpus(&pcie_syndrome->ecrc_err);
+ le32_to_cpus(&pcie_syndrome->unsupported_req);
+ le32_to_cpus(&pcie_syndrome->completer_abort);
+ le32_to_cpus(&pcie_syndrome->completion_timeout);
+ le32_to_cpus(&pcie_syndrome->addr);
+ break;
+ case DDR:
+ le16_to_cpus(&ddr_syndrome->instance);
+ le16_to_cpus(&ddr_syndrome->err_type);
+ le32_to_cpus(&ddr_syndrome->count);
+ le32_to_cpus(&ddr_syndrome->irq_status);
+ le32_to_cpus(&ddr_syndrome->data_31_0[0]);
+ le32_to_cpus(&ddr_syndrome->data_31_0[1]);
+ le32_to_cpus(&ddr_syndrome->data_63_32[0]);
+ le32_to_cpus(&ddr_syndrome->data_63_32[1]);
+ le32_to_cpus(&ddr_syndrome->data_95_64[0]);
+ le32_to_cpus(&ddr_syndrome->data_95_64[1]);
+ le32_to_cpus(&ddr_syndrome->data_127_96[0]);
+ le32_to_cpus(&ddr_syndrome->data_127_96[1]);
+ le16_to_cpus(&ddr_syndrome->parity_bits);
+ le16_to_cpus(&ddr_syndrome->addr_msb);
+ le32_to_cpus(&ddr_syndrome->addr_lsb);
+ break;
+ case SYS_BUS1:
+ le32_to_cpus(&sysbus1_syndrome->slave);
+ le32_to_cpus(&sysbus1_syndrome->err_type);
+ for (i = 0; i < 8; i++)
+ le16_to_cpus(&sysbus1_syndrome->addr[i]);
+ break;
+ case SYS_BUS2:
+ le16_to_cpus(&sysbus2_syndrome->op_type);
+ le16_to_cpus(&sysbus2_syndrome->len);
+ le16_to_cpus(&sysbus2_syndrome->redirect);
+ le16_to_cpus(&sysbus2_syndrome->path);
+ le32_to_cpus(&sysbus2_syndrome->ext_id);
+ le32_to_cpus(&sysbus2_syndrome->lsb2);
+ le32_to_cpus(&sysbus2_syndrome->msb2);
+ le32_to_cpus(&sysbus2_syndrome->lsb3);
+ le32_to_cpus(&sysbus2_syndrome->msb3);
+ break;
+ case NSP_MEM:
+ for (i = 0; i < 8; i++)
+ le32_to_cpus(&nsp_syndrome->error_address[i]);
+ break;
+ case TSENS:
+ le32_to_cpus(&tsens_syndrome->threshold_type);
+ le32_to_cpus(&tsens_syndrome->temp);
+ break;
+ }
+}
+
+static void decode_ras_msg(struct qaic_device *qdev, struct ras_data *msg)
+{
+ struct sysbus1_syndrome *sysbus1_syndrome =
+ (struct sysbus1_syndrome *)&msg->syndrome[0];
+ struct sysbus2_syndrome *sysbus2_syndrome =
+ (struct sysbus2_syndrome *)&msg->syndrome[0];
+ struct soc_mem_syndrome *soc_syndrome =
+ (struct soc_mem_syndrome *)&msg->syndrome[0];
+ struct nsp_mem_syndrome *nsp_syndrome =
+ (struct nsp_mem_syndrome *)&msg->syndrome[0];
+ struct tsens_syndrome *tsens_syndrome =
+ (struct tsens_syndrome *)&msg->syndrome[0];
+ struct pcie_syndrome *pcie_syndrome =
+ (struct pcie_syndrome *)&msg->syndrome[0];
+ struct ddr_syndrome *ddr_syndrome =
+ (struct ddr_syndrome *)&msg->syndrome[0];
+ char *class;
+ char *level;
+
+ if (msg->magic != MAGIC) {
+ pci_warn(qdev->pdev, "Dropping RAS message with invalid magic %x\n", msg->magic);
+ return;
+ }
+
+ if (msg->ver != VERSION) {
+ pci_warn(qdev->pdev, "Dropping RAS message with invalid version %d\n", msg->ver);
+ return;
+ }
+
+ if (msg->type != MSG_PUSH) {
+ pci_warn(qdev->pdev, "Dropping non-PUSH RAS message\n");
+ return;
+ }
+
+ if (msg->len != sizeof(*msg) - HDR_SZ) {
+ pci_warn(qdev->pdev, "Dropping RAS message with invalid len %d\n", msg->len);
+ return;
+ }
+
+ if (msg->err_type >= ERR_TYPE_MAX) {
+ pci_warn(qdev->pdev, "Dropping RAS message with err type %d\n", msg->err_type);
+ return;
+ }
+
+ if (msg->err_type == UE)
+ level = KERN_ERR;
+ else
+ level = KERN_WARNING;
+
+ switch (msg->source) {
+ case SOC_MEM:
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\nSyndrome:\n 0x%llx\n 0x%llx\n 0x%llx\n 0x%llx\n 0x%llx\n 0x%llx\n 0x%llx\n 0x%llx\n",
+ err_class_str[msg->err_type],
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source],
+ soc_syndrome->error_address[0],
+ soc_syndrome->error_address[1],
+ soc_syndrome->error_address[2],
+ soc_syndrome->error_address[3],
+ soc_syndrome->error_address[4],
+ soc_syndrome->error_address[5],
+ soc_syndrome->error_address[6],
+ soc_syndrome->error_address[7]);
+ break;
+ case PCIE:
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\n",
+ err_class_str[msg->err_type],
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source]);
+
+ switch (msg->err_type) {
+ case CE:
+ printk(KERN_WARNING pr_fmt("Syndrome:\n Bad TLP count %d\n Bad DLLP count %d\n Replay Rollover count %d\n Replay Timeout count %d\n Recv Error count %d\n Internal CE count %d\n"),
+ pcie_syndrome->bad_tlp,
+ pcie_syndrome->bad_dllp,
+ pcie_syndrome->replay_rollover,
+ pcie_syndrome->replay_timeout,
+ pcie_syndrome->rx_err,
+ pcie_syndrome->internal_ce_count);
+ break;
+ case UE:
+ printk(KERN_ERR pr_fmt("Syndrome:\n Index %d\n Address 0x%x\n"),
+ pcie_syndrome->index, pcie_syndrome->addr);
+ break;
+ case UE_NF:
+ printk(KERN_WARNING pr_fmt("Syndrome:\n FC timeout count %d\n Poisoned TLP count %d\n ECRC error count %d\n Unsupported request count %d\n Completer abort count %d\n Completion timeout count %d\n"),
+ pcie_syndrome->fc_timeout,
+ pcie_syndrome->poison_tlp,
+ pcie_syndrome->ecrc_err,
+ pcie_syndrome->unsupported_req,
+ pcie_syndrome->completer_abort,
+ pcie_syndrome->completion_timeout);
+ break;
+ default:
+ break;
+ }
+ break;
+ case DDR:
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\nSyndrome:\n Instance %d\n Count %d\n Data 31_0 0x%x 0x%x\n Data 63_32 0x%x 0x%x\n Data 95_64 0x%x 0x%x\n Data 127_96 0x%x 0x%x\n Parity bits 0x%x\n Address msb 0x%x\n Address lsb 0x%x\n",
+ err_class_str[msg->err_type],
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source],
+ ddr_syndrome->instance,
+ ddr_syndrome->count,
+ ddr_syndrome->data_31_0[1],
+ ddr_syndrome->data_31_0[0],
+ ddr_syndrome->data_63_32[1],
+ ddr_syndrome->data_63_32[0],
+ ddr_syndrome->data_95_64[1],
+ ddr_syndrome->data_95_64[0],
+ ddr_syndrome->data_127_96[1],
+ ddr_syndrome->data_127_96[0],
+ ddr_syndrome->parity_bits,
+ ddr_syndrome->addr_msb,
+ ddr_syndrome->addr_lsb);
+ break;
+ case SYS_BUS1:
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\nSyndome:\n instance %d\n %s\n err_type %d\n address0 0x%x\n address1 0x%x\n address2 0x%x\n address3 0x%x\n address4 0x%x\n address5 0x%x\n address6 0x%x\n address7 0x%x\n",
+ err_class_str[msg->err_type],
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source],
+ sysbus1_syndrome->instance,
+ sysbus1_syndrome->slave ? "Slave" : "Master",
+ sysbus1_syndrome->err_type,
+ sysbus1_syndrome->addr[0],
+ sysbus1_syndrome->addr[1],
+ sysbus1_syndrome->addr[2],
+ sysbus1_syndrome->addr[3],
+ sysbus1_syndrome->addr[4],
+ sysbus1_syndrome->addr[5],
+ sysbus1_syndrome->addr[6],
+ sysbus1_syndrome->addr[7]);
+ break;
+ case SYS_BUS2:
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\nSyndome:\n instance %d\n valid %d\n word error %d\n non-secure %d\n opc %d\n error code %d\n transaction type %d\n address space %d\n operation type %d\n len %d\n redirect %d\n path %d\n ext_id %d\n lsb2 %d\n msb2 %d\n lsb3 %d\n msb3 %d\n",
+ err_class_str[msg->err_type],
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source],
+ sysbus2_syndrome->instance,
+ sysbus2_syndrome->valid,
+ sysbus2_syndrome->word_error,
+ sysbus2_syndrome->non_secure,
+ sysbus2_syndrome->opc,
+ sysbus2_syndrome->error_code,
+ sysbus2_syndrome->trans_type,
+ sysbus2_syndrome->addr_space,
+ sysbus2_syndrome->op_type,
+ sysbus2_syndrome->len,
+ sysbus2_syndrome->redirect,
+ sysbus2_syndrome->path,
+ sysbus2_syndrome->ext_id,
+ sysbus2_syndrome->lsb2,
+ sysbus2_syndrome->msb2,
+ sysbus2_syndrome->lsb3,
+ sysbus2_syndrome->msb3);
+ break;
+ case NSP_MEM:
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\nSyndrome:\n NSP ID %d\n 0x%x\n 0x%x\n 0x%x\n 0x%x\n 0x%x\n 0x%x\n 0x%x\n 0x%x\n",
+ err_class_str[msg->err_type],
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source],
+ nsp_syndrome->nsp_id,
+ nsp_syndrome->error_address[0],
+ nsp_syndrome->error_address[1],
+ nsp_syndrome->error_address[2],
+ nsp_syndrome->error_address[3],
+ nsp_syndrome->error_address[4],
+ nsp_syndrome->error_address[5],
+ nsp_syndrome->error_address[6],
+ nsp_syndrome->error_address[7]);
+ break;
+ case TSENS:
+ if (tsens_syndrome->threshold_type >= NUM_TEMP_LVL) {
+ pci_warn(qdev->pdev, "Dropping RAS message with invalid temp threshold %d\n",
+ tsens_syndrome->threshold_type);
+ break;
+ }
+
+ if (msg->err_type)
+ class = "Fatal";
+ else if (tsens_syndrome->threshold_type)
+ class = "Critical";
+ else
+ class = "Warning";
+
+ pci_printk(level, qdev->pdev, "RAS event.\nClass:%s\nDescription:%s %s %s\nSyndrome:\n %s threshold\n %d deg C\n",
+ class,
+ err_type_str[msg->err_type],
+ "error from",
+ err_src_str[msg->source],
+ threshold_type_str[tsens_syndrome->threshold_type],
+ tsens_syndrome->temp);
+ break;
+ }
+
+ /* Uncorrectable errors are fatal */
+ if (msg->err_type == UE)
+ mhi_soc_reset(qdev->mhi_cntl);
+
+ switch (msg->err_type) {
+ case CE:
+ if (qdev->ce_count != UINT_MAX)
+ qdev->ce_count++;
+ break;
+ case UE:
+ if (qdev->ce_count != UINT_MAX)
+ qdev->ue_count++;
+ break;
+ case UE_NF:
+ if (qdev->ce_count != UINT_MAX)
+ qdev->ue_nf_count++;
+ break;
+ default:
+ /* not possible */
+ break;
+ }
+}
+
+static ssize_t ce_count_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct qaic_device *qdev = pci_get_drvdata(pdev);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", qdev->ce_count);
+}
+
+static ssize_t ue_count_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct qaic_device *qdev = pci_get_drvdata(pdev);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", qdev->ue_count);
+}
+
+static ssize_t ue_nonfatal_count_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct qaic_device *qdev = pci_get_drvdata(pdev);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", qdev->ue_nf_count);
+}
+
+static DEVICE_ATTR_RO(ce_count);
+static DEVICE_ATTR_RO(ue_count);
+static DEVICE_ATTR_RO(ue_nonfatal_count);
+
+static struct attribute *ras_attrs[] = {
+ &dev_attr_ce_count.attr,
+ &dev_attr_ue_count.attr,
+ &dev_attr_ue_nonfatal_count.attr,
+ NULL,
+};
+
+static struct attribute_group ras_group = {
+ .attrs = ras_attrs,
+};
+
+static int qaic_ras_mhi_probe(struct mhi_device *mhi_dev,
+ const struct mhi_device_id *id)
+{
+ struct qaic_device *qdev;
+ struct ras_data *resp;
+ int ret;
+
+ qdev = pci_get_drvdata(to_pci_dev(mhi_dev->mhi_cntrl->cntrl_dev));
+
+ dev_set_drvdata(&mhi_dev->dev, qdev);
+ qdev->ras_ch = mhi_dev;
+ ret = mhi_prepare_for_transfer(qdev->ras_ch);
+
+ if (ret)
+ return ret;
+
+ resp = kmalloc(sizeof(*resp), GFP_KERNEL);
+ if (!resp) {
+ mhi_unprepare_from_transfer(qdev->ras_ch);
+ return -ENOMEM;
+ }
+
+ ret = mhi_queue_buf(qdev->ras_ch, DMA_FROM_DEVICE, resp, sizeof(*resp),
+ MHI_EOT);
+ if (ret) {
+ mhi_unprepare_from_transfer(qdev->ras_ch);
+ return ret;
+ }
+
+ ret = device_add_group(&qdev->pdev->dev, &ras_group);
+ if (ret)
+ pci_dbg(qdev->pdev, "ras add sysfs failed %d\n", ret);
+
+ return 0;
+}
+
+static void qaic_ras_mhi_remove(struct mhi_device *mhi_dev)
+{
+ struct qaic_device *qdev;
+
+ qdev = dev_get_drvdata(&mhi_dev->dev);
+ mhi_unprepare_from_transfer(qdev->ras_ch);
+ qdev->ras_ch = NULL;
+ device_remove_group(&qdev->pdev->dev, &ras_group);
+}
+
+static void qaic_ras_mhi_ul_xfer_cb(struct mhi_device *mhi_dev,
+ struct mhi_result *mhi_result)
+{
+}
+
+static void qaic_ras_mhi_dl_xfer_cb(struct mhi_device *mhi_dev,
+ struct mhi_result *mhi_result)
+{
+ struct qaic_device *qdev = dev_get_drvdata(&mhi_dev->dev);
+ struct ras_data *msg = mhi_result->buf_addr;
+ int ret;
+
+ if (mhi_result->transaction_status) {
+ kfree(msg);
+ return;
+ }
+
+ ras_msg_to_cpu(msg);
+ decode_ras_msg(qdev, msg);
+
+ ret = mhi_queue_buf(qdev->ras_ch, DMA_FROM_DEVICE, msg, sizeof(*msg),
+ MHI_EOT);
+ if (ret) {
+ pci_err(qdev->pdev, "Cannot requeue RAS recv buf %d\n", ret);
+ kfree(msg);
+ }
+}
+
+static const struct mhi_device_id qaic_ras_mhi_match_table[] = {
+ { .chan = "QAIC_STATUS", },
+ {},
+};
+
+static struct mhi_driver qaic_ras_mhi_driver = {
+ .id_table = qaic_ras_mhi_match_table,
+ .remove = qaic_ras_mhi_remove,
+ .probe = qaic_ras_mhi_probe,
+ .ul_xfer_cb = qaic_ras_mhi_ul_xfer_cb,
+ .dl_xfer_cb = qaic_ras_mhi_dl_xfer_cb,
+ .driver = {
+ .name = "qaic_ras",
+ .owner = THIS_MODULE,
+ },
+};
+
+void qaic_ras_register(void)
+{
+ int ret;
+
+ ret = mhi_driver_register(&qaic_ras_mhi_driver);
+ if (ret)
+ pr_debug("qaic: ras register failed %d\n", ret);
+}
+
+void qaic_ras_unregister(void)
+{
+ mhi_driver_unregister(&qaic_ras_mhi_driver);
+}
diff --git a/drivers/gpu/drm/qaic/qaic_ras.h b/drivers/gpu/drm/qaic/qaic_ras.h
new file mode 100644
index 0000000..e431680
--- /dev/null
+++ b/drivers/gpu/drm/qaic/qaic_ras.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __QAIC_RAS_H__
+#define __QAIC_RAS_H__
+
+void qaic_ras_register(void);
+void qaic_ras_unregister(void);
+#endif /* __QAIC_RAS_H__ */
--
2.7.4