@@ -37,3 +37,13 @@ config PCI_EPF_VNTB
between PCI Root Port and PCIe Endpoint.
If in doubt, say "N" to disable Endpoint NTB driver.
+
+config PCI_EPF_MHI
+ tristate "PCI Endpoint driver for MHI bus"
+ depends on PCI_ENDPOINT && MHI_BUS_EP
+ help
+ Enable this configuration option to enable the PCI Endpoint
+ driver for Modem Host Interface (MHI) bus in Qualcomm Endpoint
+ devices such as SDX55.
+
+ If in doubt, say "N" to disable Endpoint driver for MHI bus.
@@ -6,3 +6,4 @@
obj-$(CONFIG_PCI_EPF_TEST) += pci-epf-test.o
obj-$(CONFIG_PCI_EPF_NTB) += pci-epf-ntb.o
obj-$(CONFIG_PCI_EPF_VNTB) += pci-epf-vntb.o
+obj-$(CONFIG_PCI_EPF_MHI) += pci-epf-mhi.o
new file mode 100644
@@ -0,0 +1,462 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI EPF driver for MHI Endpoint devices
+ *
+ * Copyright (C) 2023 Linaro Ltd.
+ * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+ */
+
+#include <linux/mhi_ep.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+
+#define MHI_VERSION_1_0 0x01000000
+
+#define to_epf_mhi(cntrl) container_of(cntrl, struct pci_epf_mhi, cntrl)
+
+struct pci_epf_mhi_ep_info {
+ const struct mhi_ep_cntrl_config *config;
+ struct pci_epf_header *epf_header;
+ enum pci_barno bar_num;
+ u32 epf_flags;
+ u32 msi_count;
+ u32 mru;
+};
+
+#define MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, direction) \
+ { \
+ .num = ch_num, \
+ .name = ch_name, \
+ .dir = direction, \
+ }
+
+#define MHI_EP_CHANNEL_CONFIG_UL(ch_num, ch_name) \
+ MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, DMA_TO_DEVICE)
+
+#define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \
+ MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, DMA_FROM_DEVICE)
+
+static const struct mhi_ep_channel_config mhi_v1_channels[] = {
+ MHI_EP_CHANNEL_CONFIG_UL(0, "LOOPBACK"),
+ MHI_EP_CHANNEL_CONFIG_DL(1, "LOOPBACK"),
+ MHI_EP_CHANNEL_CONFIG_UL(2, "SAHARA"),
+ MHI_EP_CHANNEL_CONFIG_DL(3, "SAHARA"),
+ MHI_EP_CHANNEL_CONFIG_UL(4, "DIAG"),
+ MHI_EP_CHANNEL_CONFIG_DL(5, "DIAG"),
+ MHI_EP_CHANNEL_CONFIG_UL(6, "SSR"),
+ MHI_EP_CHANNEL_CONFIG_DL(7, "SSR"),
+ MHI_EP_CHANNEL_CONFIG_UL(8, "QDSS"),
+ MHI_EP_CHANNEL_CONFIG_DL(9, "QDSS"),
+ MHI_EP_CHANNEL_CONFIG_UL(10, "EFS"),
+ MHI_EP_CHANNEL_CONFIG_DL(11, "EFS"),
+ MHI_EP_CHANNEL_CONFIG_UL(12, "MBIM"),
+ MHI_EP_CHANNEL_CONFIG_DL(13, "MBIM"),
+ MHI_EP_CHANNEL_CONFIG_UL(14, "QMI"),
+ MHI_EP_CHANNEL_CONFIG_DL(15, "QMI"),
+ MHI_EP_CHANNEL_CONFIG_UL(16, "QMI"),
+ MHI_EP_CHANNEL_CONFIG_DL(17, "QMI"),
+ MHI_EP_CHANNEL_CONFIG_UL(18, "IP-CTRL-1"),
+ MHI_EP_CHANNEL_CONFIG_DL(19, "IP-CTRL-1"),
+ MHI_EP_CHANNEL_CONFIG_UL(20, "IPCR"),
+ MHI_EP_CHANNEL_CONFIG_DL(21, "IPCR"),
+ MHI_EP_CHANNEL_CONFIG_UL(32, "DUN"),
+ MHI_EP_CHANNEL_CONFIG_DL(33, "DUN"),
+ MHI_EP_CHANNEL_CONFIG_UL(46, "IP_SW0"),
+ MHI_EP_CHANNEL_CONFIG_DL(47, "IP_SW0"),
+};
+
+static const struct mhi_ep_cntrl_config mhi_v1_config = {
+ .max_channels = 128,
+ .num_channels = ARRAY_SIZE(mhi_v1_channels),
+ .ch_cfg = mhi_v1_channels,
+ .mhi_version = MHI_VERSION_1_0,
+};
+
+static struct pci_epf_header sdx55_header = {
+ .vendorid = PCI_VENDOR_ID_QCOM,
+ .deviceid = 0x0306,
+ .baseclass_code = PCI_BASE_CLASS_COMMUNICATION,
+ .subclass_code = PCI_CLASS_COMMUNICATION_MODEM & 0xff,
+ .interrupt_pin = PCI_INTERRUPT_INTA,
+};
+
+static const struct pci_epf_mhi_ep_info sdx55_info = {
+ .config = &mhi_v1_config,
+ .epf_header = &sdx55_header,
+ .bar_num = BAR_0,
+ .epf_flags = PCI_BASE_ADDRESS_MEM_TYPE_32,
+ .msi_count = 32,
+ .mru = 0x8000,
+};
+
+struct pci_epf_mhi {
+ const struct pci_epf_mhi_ep_info *info;
+ struct mhi_ep_cntrl mhi_cntrl;
+ struct pci_epf *epf;
+ struct mutex lock;
+ void __iomem *mmio;
+ resource_size_t mmio_phys;
+ u32 mmio_size;
+ int irq;
+};
+
+static int pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr,
+ phys_addr_t *paddr, void __iomem **vaddr,
+ size_t size)
+{
+ struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
+ struct pci_epf *epf = epf_mhi->epf;
+ struct pci_epc *epc = epf_mhi->epf->epc;
+ size_t offset = pci_addr & (epc->mem->window.page_size - 1);
+ void __iomem *__vaddr;
+ phys_addr_t __paddr;
+ int ret;
+
+ __vaddr = pci_epc_mem_alloc_addr(epc, &__paddr, size + offset);
+ if (!__vaddr)
+ return -ENOMEM;
+
+ ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, __paddr,
+ pci_addr - offset, size + offset);
+ if (ret) {
+ pci_epc_mem_free_addr(epc, __paddr, __vaddr, size + offset);
+
+ return ret;
+ }
+
+ *paddr = __paddr + offset;
+ *vaddr = __vaddr + offset;
+
+ return 0;
+}
+
+static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr,
+ phys_addr_t paddr, void __iomem *vaddr,
+ size_t size)
+{
+ struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
+ struct pci_epf *epf = epf_mhi->epf;
+ struct pci_epc *epc = epf->epc;
+ size_t offset = pci_addr & (epc->mem->window.page_size - 1);
+
+ pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, paddr - offset);
+ pci_epc_mem_free_addr(epc, paddr - offset, vaddr - offset,
+ size + offset);
+}
+
+static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector)
+{
+ struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
+ struct pci_epf *epf = epf_mhi->epf;
+ struct pci_epc *epc = epf->epc;
+
+ /*
+ * MHI supplies 0 based MSI vector but the API expects the vector to be
+ * 1 based, so we need to increment the vector by 1.
+ */
+ pci_epc_raise_irq(epc, epf->func_no, epf->vfunc_no, PCI_EPC_IRQ_MSI,
+ vector + 1);
+}
+
+static int pci_epf_mhi_read_from_host(struct mhi_ep_cntrl *mhi_cntrl, u64 from,
+ void __iomem *to, size_t size)
+{
+ struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
+ struct pci_epf *epf = epf_mhi->epf;
+ struct pci_epc *epc = epf_mhi->epf->epc;
+ void __iomem *tre_buf;
+ phys_addr_t tre_phys;
+ size_t offset = from % SZ_4K;
+ int ret;
+
+ mutex_lock(&epf_mhi->lock);
+
+ tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset);
+ if (!tre_buf) {
+ ret = -ENOMEM;
+ goto err_unlock;
+ }
+
+ ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, tre_phys,
+ from - offset, size + offset);
+ if (ret) {
+ pci_epc_mem_free_addr(epc, tre_phys, tre_buf, size + offset);
+ goto err_unlock;
+ }
+
+ memcpy_fromio(to, tre_buf + offset, size);
+
+ pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, tre_phys);
+ pci_epc_mem_free_addr(epc, tre_phys, tre_buf, size + offset);
+
+err_unlock:
+ mutex_unlock(&epf_mhi->lock);
+
+ return ret;
+}
+
+static int pci_epf_mhi_write_to_host(struct mhi_ep_cntrl *mhi_cntrl,
+ void __iomem *from, u64 to, size_t size)
+{
+ struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl);
+ struct pci_epf *epf = epf_mhi->epf;
+ struct pci_epc *epc = epf_mhi->epf->epc;
+ void __iomem *tre_buf;
+ phys_addr_t tre_phys;
+ size_t offset = to % SZ_4K;
+ int ret;
+
+ mutex_lock(&epf_mhi->lock);
+
+ tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset);
+ if (!tre_buf) {
+ ret = -ENOMEM;
+ goto err_unlock;
+ }
+
+ ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, tre_phys,
+ to - offset, size + offset);
+ if (ret) {
+ pci_epc_mem_free_addr(epc, tre_phys, tre_buf, size + offset);
+ goto err_unlock;
+ }
+
+ memcpy_toio(tre_buf + offset, from, size);
+
+ pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, tre_phys);
+ pci_epc_mem_free_addr(epc, tre_phys, tre_buf, size + offset);
+
+err_unlock:
+ mutex_unlock(&epf_mhi->lock);
+
+ return ret;
+}
+
+static int pci_epf_mhi_core_init(struct pci_epf *epf)
+{
+ struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
+ const struct pci_epf_mhi_ep_info *info = epf_mhi->info;
+ struct pci_epf_bar *epf_bar = &epf->bar[info->bar_num];
+ struct pci_epc *epc = epf->epc;
+ struct device *dev = &epf->dev;
+ int ret;
+
+ epf_bar->phys_addr = epf_mhi->mmio_phys;
+ epf_bar->size = epf_mhi->mmio_size;
+ epf_bar->barno = info->bar_num;
+ epf_bar->flags = info->epf_flags;
+ ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no, epf_bar);
+ if (ret) {
+ dev_err(dev, "Failed to set BAR: %d\n", ret);
+ return ret;
+ }
+
+ ret = pci_epc_set_msi(epc, epf->func_no, epf->vfunc_no,
+ order_base_2(info->msi_count));
+ if (ret) {
+ dev_err(dev, "Failed to set MSI configuration: %d\n", ret);
+ return ret;
+ }
+
+ ret = pci_epc_write_header(epc, epf->func_no, epf->vfunc_no,
+ epf->header);
+ if (ret) {
+ dev_err(dev, "Failed to set Configuration header: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int pci_epf_mhi_link_up(struct pci_epf *epf)
+{
+ struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
+ const struct pci_epf_mhi_ep_info *info = epf_mhi->info;
+ struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl;
+ struct pci_epc *epc = epf->epc;
+ struct device *dev = &epf->dev;
+ int ret;
+
+ mhi_cntrl->mmio = epf_mhi->mmio;
+ mhi_cntrl->irq = epf_mhi->irq;
+ mhi_cntrl->mru = info->mru;
+
+ /* Assign the struct dev of PCI EP as MHI controller device */
+ mhi_cntrl->cntrl_dev = epc->dev.parent;
+ mhi_cntrl->raise_irq = pci_epf_mhi_raise_irq;
+ mhi_cntrl->alloc_map = pci_epf_mhi_alloc_map;
+ mhi_cntrl->unmap_free = pci_epf_mhi_unmap_free;
+ mhi_cntrl->read_from_host = pci_epf_mhi_read_from_host;
+ mhi_cntrl->write_to_host = pci_epf_mhi_write_to_host;
+
+ /* Register the MHI EP controller */
+ ret = mhi_ep_register_controller(mhi_cntrl, info->config);
+ if (ret) {
+ dev_err(dev, "Failed to register MHI EP controller: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int pci_epf_mhi_link_down(struct pci_epf *epf)
+{
+ struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
+ const struct pci_epf_mhi_ep_info *info = epf_mhi->info;
+ struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl;
+
+ if (mhi_cntrl->mhi_dev) {
+ mhi_ep_power_down(mhi_cntrl);
+ mhi_ep_unregister_controller(mhi_cntrl);
+ }
+
+ return 0;
+}
+
+static int pci_epf_mhi_bme(struct pci_epf *epf)
+{
+ struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
+ const struct pci_epf_mhi_ep_info *info = epf_mhi->info;
+ struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl;
+ struct device *dev = &epf->dev;
+ int ret;
+
+ /*
+ * Power up the MHI EP stack if link is up and stack is in power down
+ * state.
+ */
+ if (!mhi_cntrl->enabled && mhi_cntrl->mhi_dev) {
+ ret = mhi_ep_power_up(mhi_cntrl);
+ if (ret) {
+ dev_err(dev, "Failed to power up MHI EP: %d\n", ret);
+ mhi_ep_unregister_controller(mhi_cntrl);
+ }
+ }
+
+ return 0;
+}
+
+static int pci_epf_mhi_bind(struct pci_epf *epf)
+{
+ struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
+ struct pci_epc *epc = epf->epc;
+ struct platform_device *pdev = to_platform_device(epc->dev.parent);
+ struct device *dev = &epf->dev;
+ struct resource *res;
+ int ret;
+
+ if (WARN_ON_ONCE(!epc))
+ return -EINVAL;
+
+ /* Get MMIO base address from Endpoint controller */
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mmio");
+ epf_mhi->mmio_phys = res->start;
+ epf_mhi->mmio_size = resource_size(res);
+
+ epf_mhi->mmio = ioremap(epf_mhi->mmio_phys, epf_mhi->mmio_size);
+ if (IS_ERR(epf_mhi->mmio))
+ return PTR_ERR(epf_mhi->mmio);
+
+ ret = platform_get_irq_byname(pdev, "doorbell");
+ if (ret < 0) {
+ dev_err(dev, "Failed to get Doorbell IRQ\n");
+ iounmap(epf_mhi->mmio);
+ return ret;
+ }
+
+ epf_mhi->irq = ret;
+
+ return 0;
+}
+
+static void pci_epf_mhi_unbind(struct pci_epf *epf)
+{
+ struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
+ const struct pci_epf_mhi_ep_info *info = epf_mhi->info;
+ struct pci_epf_bar *epf_bar = &epf->bar[info->bar_num];
+ struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl;
+ struct pci_epc *epc = epf->epc;
+
+ /*
+ * Forcefully power down the MHI EP stack. Only way to bring the MHI EP
+ * stack back to working state after successive bind is by getting BME
+ * from host.
+ */
+ if (mhi_cntrl->mhi_dev) {
+ mhi_ep_power_down(mhi_cntrl);
+ mhi_ep_unregister_controller(mhi_cntrl);
+ }
+
+ iounmap(epf_mhi->mmio);
+ pci_epc_clear_bar(epc, epf->func_no, epf->vfunc_no, epf_bar);
+}
+
+static struct pci_epc_event_ops pci_epf_mhi_event_ops = {
+ .core_init = pci_epf_mhi_core_init,
+ .link_up = pci_epf_mhi_link_up,
+ .link_down = pci_epf_mhi_link_down,
+ .bme = pci_epf_mhi_bme,
+};
+
+static int pci_epf_mhi_probe(struct pci_epf *epf,
+ const struct pci_epf_device_id *id)
+{
+ struct pci_epf_mhi_ep_info *info =
+ (struct pci_epf_mhi_ep_info *)id->driver_data;
+ struct pci_epf_mhi *epf_mhi;
+ struct device *dev = &epf->dev;
+
+ epf_mhi = devm_kzalloc(dev, sizeof(*epf_mhi), GFP_KERNEL);
+ if (!epf_mhi)
+ return -ENOMEM;
+
+ epf->header = info->epf_header;
+ epf_mhi->info = info;
+ epf_mhi->epf = epf;
+
+ epf->event_ops = &pci_epf_mhi_event_ops;
+
+ mutex_init(&epf_mhi->lock);
+
+ epf_set_drvdata(epf, epf_mhi);
+
+ return 0;
+}
+
+static const struct pci_epf_device_id pci_epf_mhi_ids[] = {
+ {
+ .name = "sdx55", .driver_data = (kernel_ulong_t)&sdx55_info,
+ },
+ {},
+};
+
+static struct pci_epf_ops pci_epf_mhi_ops = {
+ .unbind = pci_epf_mhi_unbind,
+ .bind = pci_epf_mhi_bind,
+};
+
+static struct pci_epf_driver pci_epf_mhi_driver = {
+ .driver.name = "pci_epf_mhi",
+ .probe = pci_epf_mhi_probe,
+ .id_table = pci_epf_mhi_ids,
+ .ops = &pci_epf_mhi_ops,
+ .owner = THIS_MODULE,
+};
+
+static int __init pci_epf_mhi_init(void)
+{
+ return pci_epf_register_driver(&pci_epf_mhi_driver);
+}
+module_init(pci_epf_mhi_init);
+
+static void __exit pci_epf_mhi_exit(void)
+{
+ pci_epf_unregister_driver(&pci_epf_mhi_driver);
+}
+module_exit(pci_epf_mhi_exit);
+
+MODULE_DESCRIPTION("PCI EPF driver for MHI Endpoint devices");
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
+MODULE_LICENSE("GPL");