[RFC PATCH 04/14] drm/qaic: Add MHI controller

From: Jeffrey Hugo
Date: Mon Aug 15 2022 - 15:33:38 EST


A QAIC device contains a MHI interface with a number of different channels
for controlling different aspects of the device. The MHI controller works
with the MHI bus to enable and drive that interface.

Change-Id: I77363193b1a2dece7abab287a6acef3cac1b4e1b
Signed-off-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
---
drivers/gpu/drm/qaic/mhi_controller.c | 575 ++++++++++++++++++++++++++++++++++
drivers/gpu/drm/qaic/mhi_controller.h | 18 ++
2 files changed, 593 insertions(+)
create mode 100644 drivers/gpu/drm/qaic/mhi_controller.c
create mode 100644 drivers/gpu/drm/qaic/mhi_controller.h

diff --git a/drivers/gpu/drm/qaic/mhi_controller.c b/drivers/gpu/drm/qaic/mhi_controller.c
new file mode 100644
index 0000000..e88e0fe
--- /dev/null
+++ b/drivers/gpu/drm/qaic/mhi_controller.c
@@ -0,0 +1,575 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/* Copyright (c) 2019-2021, The Linux Foundation. All rights reserved. */
+/* Copyright (c) 2021-2022 Qualcomm Innovation Center, Inc. All rights reserved. */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/memblock.h>
+#include <linux/mhi.h>
+#include <linux/moduleparam.h>
+#include <linux/pci.h>
+#include <linux/sizes.h>
+
+#include "mhi_controller.h"
+#include "qaic.h"
+
+#define MAX_RESET_TIME_SEC 25
+
+static unsigned int mhi_timeout = 2000; /* 2 sec default */
+module_param(mhi_timeout, uint, 0600);
+
+static struct mhi_channel_config aic100_channels[] = {
+ {
+ .name = "QAIC_LOOPBACK",
+ .num = 0,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_LOOPBACK",
+ .num = 1,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_SAHARA",
+ .num = 2,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_SBL,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_SAHARA",
+ .num = 3,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_SBL,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_DIAG",
+ .num = 4,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_DIAG",
+ .num = 5,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_SSR",
+ .num = 6,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_SSR",
+ .num = 7,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_QDSS",
+ .num = 8,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_QDSS",
+ .num = 9,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_CONTROL",
+ .num = 10,
+ .num_elements = 128,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_CONTROL",
+ .num = 11,
+ .num_elements = 128,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_LOGGING",
+ .num = 12,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_SBL,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_LOGGING",
+ .num = 13,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_SBL,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_STATUS",
+ .num = 14,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_STATUS",
+ .num = 15,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_TELEMETRY",
+ .num = 16,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_TELEMETRY",
+ .num = 17,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_DEBUG",
+ .num = 18,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_DEBUG",
+ .num = 19,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .name = "QAIC_TIMESYNC",
+ .num = 20,
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_TO_DEVICE,
+ .ee_mask = MHI_CH_EE_SBL | MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+ {
+ .num = 21,
+ .name = "QAIC_TIMESYNC",
+ .num_elements = 32,
+ .local_elements = 0,
+ .event_ring = 0,
+ .dir = DMA_FROM_DEVICE,
+ .ee_mask = MHI_CH_EE_SBL | MHI_CH_EE_AMSS,
+ .pollcfg = 0,
+ .doorbell = MHI_DB_BRST_DISABLE,
+ .lpm_notify = false,
+ .offload_channel = false,
+ .doorbell_mode_switch = false,
+ .auto_queue = false,
+ .wake_capable = false,
+ },
+};
+
+static struct mhi_event_config aic100_events[] = {
+ {
+ .num_elements = 32,
+ .irq_moderation_ms = 0,
+ .irq = 0,
+ .channel = U32_MAX,
+ .priority = 1,
+ .mode = MHI_DB_BRST_DISABLE,
+ .data_type = MHI_ER_CTRL,
+ .hardware_event = false,
+ .client_managed = false,
+ .offload_channel = false,
+ },
+};
+
+static struct mhi_controller_config aic100_config = {
+ .max_channels = 128,
+ .timeout_ms = 0, /* controlled by mhi_timeout */
+ .buf_len = 0,
+ .num_channels = ARRAY_SIZE(aic100_channels),
+ .ch_cfg = aic100_channels,
+ .num_events = ARRAY_SIZE(aic100_events),
+ .event_cfg = aic100_events,
+ .use_bounce_buf = false,
+ .m2_no_db = false,
+};
+
+static int mhi_read_reg(struct mhi_controller *mhi_cntl, void __iomem *addr, u32 *out)
+{
+ u32 tmp = readl_relaxed(addr);
+
+ if (tmp == U32_MAX)
+ return -EIO;
+
+ *out = tmp;
+
+ return 0;
+}
+
+static void mhi_write_reg(struct mhi_controller *mhi_cntl, void __iomem *addr,
+ u32 val)
+{
+ writel_relaxed(val, addr);
+}
+
+static int mhi_runtime_get(struct mhi_controller *mhi_cntl)
+{
+ return 0;
+}
+
+static void mhi_runtime_put(struct mhi_controller *mhi_cntl)
+{
+}
+
+static void mhi_status_cb(struct mhi_controller *mhi_cntl, enum mhi_callback reason)
+{
+ struct qaic_device *qdev = pci_get_drvdata(to_pci_dev(mhi_cntl->cntrl_dev));
+
+ /* this event occurs in atomic context */
+ if (reason == MHI_CB_FATAL_ERROR)
+ pci_err(qdev->pdev, "Fatal error received from device. Attempting to recover\n");
+ /* this event occurs in non-atomic context */
+ if (reason == MHI_CB_SYS_ERROR && !qdev->in_reset)
+ qaic_dev_reset_clean_local_state(qdev, true);
+}
+
+static int mhi_reset_and_async_power_up(struct mhi_controller *mhi_cntl)
+{
+ char time_sec = 1;
+ int current_ee;
+ int ret;
+
+ /* Reset the device to bring the device in PBL EE */
+ mhi_soc_reset(mhi_cntl);
+
+ /*
+ * Keep checking the execution environment(EE) after every 1 second
+ * interval.
+ */
+ do {
+ msleep(1000);
+ current_ee = mhi_get_exec_env(mhi_cntl);
+ } while (current_ee != MHI_EE_PBL && time_sec++ <= MAX_RESET_TIME_SEC);
+
+ /* If the device is in PBL EE retry power up */
+ if (current_ee == MHI_EE_PBL)
+ ret = mhi_async_power_up(mhi_cntl);
+ else
+ ret = -EIO;
+
+ return ret;
+}
+
+struct mhi_controller *qaic_mhi_register_controller(struct pci_dev *pci_dev,
+ void __iomem *mhi_bar,
+ int mhi_irq)
+{
+ struct mhi_controller *mhi_cntl;
+ int ret;
+
+ mhi_cntl = kzalloc(sizeof(*mhi_cntl), GFP_KERNEL);
+ if (!mhi_cntl)
+ return ERR_PTR(-ENOMEM);
+
+ mhi_cntl->cntrl_dev = &pci_dev->dev;
+
+ /*
+ * Covers the entire possible physical ram region. Remote side is
+ * going to calculate a size of this range, so subtract 1 to prevent
+ * rollover.
+ */
+ mhi_cntl->iova_start = 0;
+ mhi_cntl->iova_stop = PHYS_ADDR_MAX - 1;
+
+ mhi_cntl->status_cb = mhi_status_cb;
+ mhi_cntl->runtime_get = mhi_runtime_get;
+ mhi_cntl->runtime_put = mhi_runtime_put;
+ mhi_cntl->read_reg = mhi_read_reg;
+ mhi_cntl->write_reg = mhi_write_reg;
+ mhi_cntl->regs = mhi_bar;
+ mhi_cntl->reg_len = SZ_4K;
+ mhi_cntl->nr_irqs = 1;
+ mhi_cntl->irq = kmalloc(sizeof(*mhi_cntl->irq), GFP_KERNEL);
+
+ if (!mhi_cntl->irq) {
+ kfree(mhi_cntl);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ mhi_cntl->irq[0] = mhi_irq;
+
+ mhi_cntl->fw_image = "qcom/aic100/sbl.bin";
+
+ /* use latest configured timeout */
+ aic100_config.timeout_ms = mhi_timeout;
+ ret = mhi_register_controller(mhi_cntl, &aic100_config);
+ if (ret) {
+ pci_err(pci_dev, "mhi_register_controller failed %d\n", ret);
+ kfree(mhi_cntl->irq);
+ kfree(mhi_cntl);
+ return ERR_PTR(ret);
+ }
+
+ ret = mhi_prepare_for_power_up(mhi_cntl);
+ if (ret) {
+ pci_err(pci_dev, "mhi_prepare_for_power_up failed %d\n", ret);
+ mhi_unregister_controller(mhi_cntl);
+ kfree(mhi_cntl->irq);
+ kfree(mhi_cntl);
+ return ERR_PTR(ret);
+ }
+
+ ret = mhi_async_power_up(mhi_cntl);
+ /*
+ * If EIO is returned it is possible that device is in SBL EE, which is
+ * undesired. SOC reset the device and try to power up again.
+ */
+ if (ret == -EIO && MHI_EE_SBL == mhi_get_exec_env(mhi_cntl)) {
+ pci_err(pci_dev, "Device is not expected to be SBL EE. SOC resetting the device to put it in PBL EE and again trying mhi async power up. Error %d\n",
+ ret);
+ ret = mhi_reset_and_async_power_up(mhi_cntl);
+ }
+
+ if (ret) {
+ pci_err(pci_dev, "mhi_async_power_up failed %d\n", ret);
+ mhi_unprepare_after_power_down(mhi_cntl);
+ mhi_unregister_controller(mhi_cntl);
+ kfree(mhi_cntl->irq);
+ kfree(mhi_cntl);
+ return ERR_PTR(ret);
+ }
+
+ return mhi_cntl;
+}
+
+void qaic_mhi_free_controller(struct mhi_controller *mhi_cntl, bool link_up)
+{
+ mhi_power_down(mhi_cntl, link_up);
+ mhi_unprepare_after_power_down(mhi_cntl);
+ mhi_unregister_controller(mhi_cntl);
+ kfree(mhi_cntl->irq);
+ kfree(mhi_cntl);
+}
+
+void qaic_mhi_start_reset(struct mhi_controller *mhi_cntl)
+{
+ mhi_power_down(mhi_cntl, true);
+}
+
+void qaic_mhi_reset_done(struct mhi_controller *mhi_cntl)
+{
+ struct pci_dev *pci_dev = container_of(mhi_cntl->cntrl_dev,
+ struct pci_dev, dev);
+ int ret;
+
+ ret = mhi_async_power_up(mhi_cntl);
+ if (ret)
+ pci_err(pci_dev, "mhi_async_power_up failed after reset %d\n", ret);
+}
diff --git a/drivers/gpu/drm/qaic/mhi_controller.h b/drivers/gpu/drm/qaic/mhi_controller.h
new file mode 100644
index 0000000..5a739bb
--- /dev/null
+++ b/drivers/gpu/drm/qaic/mhi_controller.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2019-2020, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef MHICONTROLLERQAIC_H_
+#define MHICONTROLLERQAIC_H_
+
+struct mhi_controller *qaic_mhi_register_controller(struct pci_dev *pci_dev,
+ void __iomem *mhi_bar,
+ int mhi_irq);
+
+void qaic_mhi_free_controller(struct mhi_controller *mhi_cntl, bool link_up);
+
+void qaic_mhi_start_reset(struct mhi_controller *mhi_cntl);
+void qaic_mhi_reset_done(struct mhi_controller *mhi_cntl);
+
+#endif /* MHICONTROLLERQAIC_H_ */
--
2.7.4