@@ -20,3 +20,12 @@ config MHI_BUS_DEBUG
Enable debugfs support for use with the MHI transport. Allows
reading and/or modifying some values within the MHI controller
for debug and test purposes.
+
+config MHI_BUS_PCI_GENERIC
+ tristate "MHI PCI controller driver"
+ depends on MHI_BUS
+ depends on PCI
+ help
+ This driver provides MHI PCI controller driver for devices such as
+ Qualcomm SDX55 based PCIe modems.
+
@@ -1,2 +1,6 @@
# core layer
obj-y += core/
+
+obj-$(CONFIG_MHI_BUS_PCI_GENERIC) += mhi_pci_generic.o
+mhi_pci_generic-y += pci_generic.o
+
new file mode 100644
@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MHI PCI driver - MHI over PCI controller driver
+ *
+ * This module is a generic driver for registering MHI-over-PCI devices,
+ * such as PCIe QCOM modems.
+ *
+ * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org>
+ */
+
+#include <linux/device.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#define MHI_PCI_DEFAULT_BAR_NUM 0
+
+/**
+ * struct mhi_pci_dev_info - MHI PCI device specific information
+ * @config: MHI controller configuration
+ * @name: name of the PCI module
+ * @fw: firmware path (if any)
+ * @edl: emergency download mode firmware path (if any)
+ * @bar_num: PCI base address register to use for MHI MMIO register space
+ * @dma_data_width: DMA transfer word size (32 or 64 bits)
+ */
+struct mhi_pci_dev_info {
+ const struct mhi_controller_config *config;
+ const char *name;
+ const char *fw;
+ const char *edl;
+ unsigned int bar_num;
+ unsigned int dma_data_width;
+};
+
+#define MHI_CHANNEL_CONFIG_UL(ch_num, ch_name, el_count, ev_ring) \
+ { \
+ .num = ch_num, \
+ .name = ch_name, \
+ .num_elements = el_count, \
+ .event_ring = ev_ring, \
+ .dir = DMA_TO_DEVICE, \
+ .ee_mask = BIT(MHI_EE_AMSS), \
+ .pollcfg = 0, \
+ .doorbell = MHI_DB_BRST_DISABLE, \
+ .lpm_notify = false, \
+ .offload_channel = false, \
+ .doorbell_mode_switch = false, \
+ } \
+
+#define MHI_CHANNEL_CONFIG_DL(ch_num, ch_name, el_count, ev_ring) \
+ { \
+ .num = ch_num, \
+ .name = ch_name, \
+ .num_elements = el_count, \
+ .event_ring = ev_ring, \
+ .dir = DMA_FROM_DEVICE, \
+ .ee_mask = BIT(MHI_EE_AMSS), \
+ .pollcfg = 0, \
+ .doorbell = MHI_DB_BRST_DISABLE, \
+ .lpm_notify = false, \
+ .offload_channel = false, \
+ .doorbell_mode_switch = false, \
+ }
+
+#define MHI_EVENT_CONFIG_CTRL(ev_ring) \
+ { \
+ .num_elements = 64, \
+ .irq_moderation_ms = 0, \
+ .irq = (ev_ring) + 1, \
+ .priority = 1, \
+ .mode = MHI_DB_BRST_DISABLE, \
+ .data_type = MHI_ER_CTRL, \
+ .hardware_event = false, \
+ .client_managed = false, \
+ .offload_channel = false, \
+ }
+
+#define MHI_EVENT_CONFIG_DATA(ev_ring) \
+ { \
+ .num_elements = 128, \
+ .irq_moderation_ms = 5, \
+ .irq = (ev_ring) + 1, \
+ .priority = 1, \
+ .mode = MHI_DB_BRST_DISABLE, \
+ .data_type = MHI_ER_DATA, \
+ .hardware_event = false, \
+ .client_managed = false, \
+ .offload_channel = false, \
+ }
+
+#define MHI_EVENT_CONFIG_HW_DATA(ev_ring, ch_num) \
+ { \
+ .num_elements = 128, \
+ .irq_moderation_ms = 5, \
+ .irq = (ev_ring) + 1, \
+ .priority = 1, \
+ .mode = MHI_DB_BRST_DISABLE, \
+ .data_type = MHI_ER_DATA, \
+ .hardware_event = true, \
+ .client_managed = false, \
+ .offload_channel = false, \
+ .channel = ch_num, \
+ }
+
+static const struct mhi_channel_config modem_qcom_v1_mhi_channels[] = {
+ MHI_CHANNEL_CONFIG_UL(12, "MBIM", 4, 0),
+ MHI_CHANNEL_CONFIG_DL(13, "MBIM", 4, 0),
+ MHI_CHANNEL_CONFIG_UL(14, "QMI", 4, 0),
+ MHI_CHANNEL_CONFIG_DL(15, "QMI", 4, 0),
+ MHI_CHANNEL_CONFIG_UL(20, "IPCR", 8, 0),
+ MHI_CHANNEL_CONFIG_DL(21, "IPCR", 8, 0),
+ MHI_CHANNEL_CONFIG_UL(100, "IP_HW0", 128, 1),
+ MHI_CHANNEL_CONFIG_DL(101, "IP_HW0", 128, 2),
+};
+
+static const struct mhi_event_config modem_qcom_v1_mhi_events[] = {
+ /* first ring is control+data ring */
+ MHI_EVENT_CONFIG_CTRL(0),
+ /* Hardware channels request dedicated hardware event rings */
+ MHI_EVENT_CONFIG_HW_DATA(1, 100),
+ MHI_EVENT_CONFIG_HW_DATA(2, 101)
+};
+
+static const struct mhi_controller_config modem_qcom_v1_mhiv_config = {
+ .max_channels = 128,
+ .timeout_ms = 5000,
+ .num_channels = ARRAY_SIZE(modem_qcom_v1_mhi_channels),
+ .ch_cfg = modem_qcom_v1_mhi_channels,
+ .num_events = ARRAY_SIZE(modem_qcom_v1_mhi_events),
+ .event_cfg = modem_qcom_v1_mhi_events,
+};
+
+static const struct mhi_pci_dev_info mhi_qcom_sdx55_info = {
+ .name = "qcom-sdx55m",
+ .fw = "qcom/sdx55m/sbl1.mbn",
+ .edl = "qcom/sdx55m/edl.mbn",
+ .config = &modem_qcom_v1_mhiv_config,
+ .bar_num = MHI_PCI_DEFAULT_BAR_NUM,
+ .dma_data_width = 32
+};
+
+static const struct pci_device_id mhi_pci_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_QCOM, 0x0306),
+ .driver_data = (kernel_ulong_t) &mhi_qcom_sdx55_info },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, mhi_pci_id_table);
+
+static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl,
+ void __iomem *addr, u32 *out)
+{
+ *out = readl(addr);
+ return 0;
+}
+
+static void mhi_pci_write_reg(struct mhi_controller *mhi_cntrl,
+ void __iomem *addr, u32 val)
+{
+ writel(val, addr);
+}
+
+static void mhi_pci_status_cb(struct mhi_controller *mhi_cntrl,
+ enum mhi_callback cb)
+{
+ /* Nothing to do for now */
+}
+
+static int mhi_pci_claim(struct mhi_controller *mhi_cntrl,
+ unsigned int bar_num, u64 dma_mask)
+{
+ struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+ int err;
+
+ err = pci_assign_resource(pdev, bar_num);
+ if (err)
+ return err;
+
+ err = pcim_enable_device(pdev);
+ if (err) {
+ dev_err(&pdev->dev, "failed to enable pci device: %d\n", err);
+ return err;
+ }
+
+ err = pcim_iomap_regions(pdev, 1 << bar_num, pci_name(pdev));
+ if (err) {
+ dev_err(&pdev->dev, "failed to map pci region: %d\n", err);
+ return err;
+ }
+ mhi_cntrl->regs = pcim_iomap_table(pdev)[bar_num];
+
+ err = pci_set_dma_mask(pdev, dma_mask);
+ if (err) {
+ dev_err(&pdev->dev, "Cannot set proper DMA mask\n");
+ return err;
+ }
+
+ err = pci_set_consistent_dma_mask(pdev, dma_mask);
+ if (err) {
+ dev_err(&pdev->dev, "set consistent dma mask failed\n");
+ return err;
+ }
+
+ pci_set_master(pdev);
+
+ return 0;
+}
+
+static int mhi_pci_get_irqs(struct mhi_controller *mhi_cntrl,
+ const struct mhi_controller_config *mhi_cntrl_config)
+{
+ struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev);
+ int nr_vectors, i;
+ int *irq;
+
+ /*
+ * Alloc one MSI vector for BHI + one vector per event ring, ideally...
+ * No explicit pci_free_irq_vectors required, done by pcim_release.
+ */
+ mhi_cntrl->nr_irqs = 1 + mhi_cntrl_config->num_events;
+
+ nr_vectors = pci_alloc_irq_vectors(pdev, 1, mhi_cntrl->nr_irqs, PCI_IRQ_MSI);
+ if (nr_vectors < 0) {
+ dev_err(&pdev->dev, "Error allocating MSI vectors %d\n",
+ nr_vectors);
+ return nr_vectors;
+ }
+
+ if (nr_vectors < mhi_cntrl->nr_irqs) {
+ dev_warn(&pdev->dev, "Not enough MSI vectors (%d/%d), use shared MSI\n",
+ nr_vectors, mhi_cntrl_config->num_events);
+ }
+
+ irq = devm_kcalloc(&pdev->dev, mhi_cntrl->nr_irqs, sizeof(int), GFP_KERNEL);
+ if (!irq)
+ return -ENOMEM;
+
+ for (i = 0; i < mhi_cntrl->nr_irqs; i++) {
+ int vector = i >= nr_vectors ? (nr_vectors - 1) : i;
+
+ irq[i] = pci_irq_vector(pdev, vector);
+ }
+
+ mhi_cntrl->irq = irq;
+
+ return 0;
+}
+
+static int mhi_pci_runtime_get(struct mhi_controller *mhi_cntrl)
+{
+ /* no PM for now */
+ return 0;
+}
+
+static void mhi_pci_runtime_put(struct mhi_controller *mhi_cntrl)
+{
+ /* no PM for now */
+}
+
+static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ const struct mhi_pci_dev_info *info = (struct mhi_pci_dev_info *) id->driver_data;
+ const struct mhi_controller_config *mhi_cntrl_config;
+ struct mhi_controller *mhi_cntrl;
+ int err;
+
+ dev_dbg(&pdev->dev, "MHI PCI device found: %s\n", info->name);
+
+ mhi_cntrl = mhi_alloc_controller();
+ if (!mhi_cntrl)
+ return -ENOMEM;
+
+ mhi_cntrl_config = info->config;
+ mhi_cntrl->cntrl_dev = &pdev->dev;
+ mhi_cntrl->iova_start = 0;
+ mhi_cntrl->iova_stop = DMA_BIT_MASK(info->dma_data_width);
+ mhi_cntrl->fw_image = info->fw;
+ mhi_cntrl->edl_image = info->edl;
+
+ mhi_cntrl->read_reg = mhi_pci_read_reg;
+ mhi_cntrl->write_reg = mhi_pci_write_reg;
+ mhi_cntrl->status_cb = mhi_pci_status_cb;
+ mhi_cntrl->runtime_get = mhi_pci_runtime_get;
+ mhi_cntrl->runtime_put = mhi_pci_runtime_put;
+
+ err = mhi_pci_claim(mhi_cntrl, info->bar_num, DMA_BIT_MASK(info->dma_data_width));
+ if (err)
+ goto err_release;
+
+ err = mhi_pci_get_irqs(mhi_cntrl, mhi_cntrl_config);
+ if (err)
+ goto err_release;
+
+ pci_set_drvdata(pdev, mhi_cntrl);
+
+ err = mhi_register_controller(mhi_cntrl, mhi_cntrl_config);
+ if (err)
+ goto err_release;
+
+ /* MHI bus does not power up the controller by default */
+ err = mhi_prepare_for_power_up(mhi_cntrl);
+ if (err) {
+ dev_err(&pdev->dev, "failed to prepare MHI controller\n");
+ goto err_unregister;
+ }
+
+ err = mhi_sync_power_up(mhi_cntrl);
+ if (err) {
+ dev_err(&pdev->dev, "failed to power up MHI controller\n");
+ goto err_unprepare;
+ }
+
+ return 0;
+
+err_unprepare:
+ mhi_unprepare_after_power_down(mhi_cntrl);
+err_unregister:
+ mhi_unregister_controller(mhi_cntrl);
+err_release:
+ mhi_free_controller(mhi_cntrl);
+
+ return err;
+}
+
+static void mhi_pci_remove(struct pci_dev *pdev)
+{
+ struct mhi_controller *mhi_cntrl = pci_get_drvdata(pdev);
+
+ mhi_power_down(mhi_cntrl, true);
+ mhi_unprepare_after_power_down(mhi_cntrl);
+ mhi_unregister_controller(mhi_cntrl);
+ mhi_free_controller(mhi_cntrl);
+}
+
+static struct pci_driver mhi_pci_driver = {
+ .name = "mhi-pci-generic",
+ .id_table = mhi_pci_id_table,
+ .probe = mhi_pci_probe,
+ .remove = mhi_pci_remove
+};
+module_pci_driver(mhi_pci_driver);
+
+MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
+MODULE_DESCRIPTION("Modem Host Interface (MHI) PCI controller driver");
+MODULE_LICENSE("GPL");