bus: mhi: Move host MHI code to "host" directory

[ Upstream commit a0f5a630668cb8b2ebf5204f08e957875e991780 ]

In preparation of the endpoint MHI support, let's move the host MHI code
to its own "host" directory and adjust the toplevel MHI Kconfig & Makefile.

While at it, let's also move the "pci_generic" driver to "host" directory
as it is a host MHI controller driver.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 6a0c637bfee6 ("bus: mhi: host: Range check CHDBOFF and ERDBOFF")
Signed-off-by: Sasha Levin <sashal@kernel.org>

1 files changed, 345 insertions, 0 deletions

diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
new file mode 100644
index 000000000000..e3df838c3c80
--- /dev/null
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -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");