| Message ID | 20230519144215.25167-8-manivannan.sadhasivam@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Add support for MHI Endpoint function driver | expand |
On Fri, May 19, 2023 at 08:12:15PM +0530, Manivannan Sadhasivam wrote: > Add PCI Endpoint driver for the Qualcomm MHI (Modem Host Interface) bus. > The driver implements the MHI function over PCI in the endpoint device > such as SDX55 modem. The MHI endpoint function driver acts as a > controller driver for the MHI Endpoint stack and carries out all PCI > related activities like mapping the host memory using iATU, triggering > MSIs etc... > > Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > --- > drivers/pci/endpoint/functions/Kconfig | 10 + > drivers/pci/endpoint/functions/Makefile | 1 + > drivers/pci/endpoint/functions/pci-epf-mhi.c | 454 +++++++++++++++++++ > 3 files changed, 465 insertions(+) > create mode 100644 drivers/pci/endpoint/functions/pci-epf-mhi.c > > diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig > index 9fd560886871..f5171b4fabbe 100644 > --- a/drivers/pci/endpoint/functions/Kconfig > +++ b/drivers/pci/endpoint/functions/Kconfig > @@ -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. > diff --git a/drivers/pci/endpoint/functions/Makefile b/drivers/pci/endpoint/functions/Makefile > index 5c13001deaba..696473fce50e 100644 > --- a/drivers/pci/endpoint/functions/Makefile > +++ b/drivers/pci/endpoint/functions/Makefile > @@ -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 > diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c > new file mode 100644 > index 000000000000..df924fb10e4d > --- /dev/null > +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c > @@ -0,0 +1,454 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * PCI EPF driver for MHI Endpoint devices > + * > + * Copyright (C) 2022 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 > + > +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_UL(ch_num, ch_name) \ > + { \ > + .num = ch_num, \ > + .name = ch_name, \ > + .dir = DMA_TO_DEVICE, \ > + } > + > +#define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \ > + { \ > + .num = ch_num, \ > + .name = ch_name, \ > + .dir = DMA_FROM_DEVICE, \ > + } You can define it as: #define MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, dir) \ { \ .num = ch_num, \ .name = ch_name, \ .dir = dir, \ } #define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \ MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, DMA_FROM_DEVICE) etc. > + > +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; > + bool mhi_registered; Do we really need this variable ? Can't it be inferred from the framework ? > +}; > + > +static int pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, > + phys_addr_t *phys_ptr, void __iomem **virt, size_t size) > +{ > + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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 *virt_addr; > + phys_addr_t phys_addr; > + int ret; > + > + virt_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, size + offset); > + if (!virt_addr) > + return -ENOMEM; > + > + ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, phys_addr, pci_addr - offset, > + size + offset); > + if (ret) { > + pci_epc_mem_free_addr(epc, phys_addr, virt_addr, size + offset); > + > + return ret; > + } > + > + *phys_ptr = phys_addr + offset; > + *virt = virt_addr + offset; > + > + return 0; > +} > + > +static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, > + phys_addr_t phys_addr, void __iomem *virt_addr, size_t size) > +{ > + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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, phys_addr - offset); > + pci_epc_mem_free_addr(epc, phys_addr - offset, virt_addr - offset, size + offset); > +} > + > +static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector) > +{ > + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_epf_mhi, mhi_cntrl); > + struct pci_epf *epf = epf_mhi->epf; > + struct pci_epc *epc = epf->epc; > + > + /* > + * Vector is incremented by 1 here as the DWC core will decrement it before > + * writing to iATU. This isn't OK. It is an API, you can't write code explicitly relying on the underlying implementation. I assume the API is not well specified, that's why we need these tricks ? > + */ > + 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 = container_of(mhi_cntrl, struct pci_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 % 0x1000; Explain what 0x1000 represents - make it a macro if that helps > + int ret; > + > + mutex_lock(&epf_mhi->lock); > + > + tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset); > + if (!tre_buf) { > + mutex_unlock(&epf_mhi->lock); > + return -ENOMEM; > + } > + > + 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); > + mutex_unlock(&epf_mhi->lock); I'd prefer a single goto label instead of repeating the code for every branch taken but that's up to you. > + return ret; > + } > + > + 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); > + > + mutex_unlock(&epf_mhi->lock); > + > + return 0; > +} > + > +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 = container_of(mhi_cntrl, struct pci_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 % 0x1000; Ditto as above. > + int ret; > + > + mutex_lock(&epf_mhi->lock); > + > + tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset); > + if (!tre_buf) { > + mutex_unlock(&epf_mhi->lock); > + return -ENOMEM; > + } > + > + 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); > + mutex_unlock(&epf_mhi->lock); Ditto. > + return ret; > + } > + > + 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); > + > + mutex_unlock(&epf_mhi->lock); > + > + return 0; > +} > + > +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; > + } > + > + epf_mhi->mhi_registered = true; I don't like this. It should be part of mhi_ep_register_controller(); > + > + return 0; > +} > + > +static int pci_epf_mhi_link_down(struct pci_epf *epf) > +{ > + struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); > + struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; > + > + if (epf_mhi->mhi_registered) { > + mhi_ep_power_down(mhi_cntrl); > + mhi_ep_unregister_controller(mhi_cntrl); > + epf_mhi->mhi_registered = false; > + } > + > + return 0; > +} > + > +static int pci_epf_mhi_bme(struct pci_epf *epf) > +{ > + struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); > + 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 && epf_mhi->mhi_registered) { > + 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); > + epf_mhi->mhi_registered = false; > + } > + } > + > + 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_wc(epf_mhi->mmio_phys, epf_mhi->mmio_size); ioremap_wc(). Why wc mappings ? Please explain. Thanks, Lorenzo > + 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 (epf_mhi->mhi_registered) { > + mhi_ep_power_down(mhi_cntrl); > + mhi_ep_unregister_controller(mhi_cntrl); > + epf_mhi->mhi_registered = false; > + } > + > + 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"); > -- > 2.25.1 >
On Mon, May 29, 2023 at 03:11:17PM +0200, Lorenzo Pieralisi wrote: > On Fri, May 19, 2023 at 08:12:15PM +0530, Manivannan Sadhasivam wrote: > > Add PCI Endpoint driver for the Qualcomm MHI (Modem Host Interface) bus. > > The driver implements the MHI function over PCI in the endpoint device > > such as SDX55 modem. The MHI endpoint function driver acts as a > > controller driver for the MHI Endpoint stack and carries out all PCI > > related activities like mapping the host memory using iATU, triggering > > MSIs etc... > > > > Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org> > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> > > --- > > drivers/pci/endpoint/functions/Kconfig | 10 + > > drivers/pci/endpoint/functions/Makefile | 1 + > > drivers/pci/endpoint/functions/pci-epf-mhi.c | 454 +++++++++++++++++++ > > 3 files changed, 465 insertions(+) > > create mode 100644 drivers/pci/endpoint/functions/pci-epf-mhi.c > > > > diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig > > index 9fd560886871..f5171b4fabbe 100644 > > --- a/drivers/pci/endpoint/functions/Kconfig > > +++ b/drivers/pci/endpoint/functions/Kconfig > > @@ -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. > > diff --git a/drivers/pci/endpoint/functions/Makefile b/drivers/pci/endpoint/functions/Makefile > > index 5c13001deaba..696473fce50e 100644 > > --- a/drivers/pci/endpoint/functions/Makefile > > +++ b/drivers/pci/endpoint/functions/Makefile > > @@ -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 > > diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c > > new file mode 100644 > > index 000000000000..df924fb10e4d > > --- /dev/null > > +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c [...] > > +#define MHI_EP_CHANNEL_CONFIG_UL(ch_num, ch_name) \ > > + { \ > > + .num = ch_num, \ > > + .name = ch_name, \ > > + .dir = DMA_TO_DEVICE, \ > > + } > > + > > +#define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \ > > + { \ > > + .num = ch_num, \ > > + .name = ch_name, \ > > + .dir = DMA_FROM_DEVICE, \ > > + } > > You can define it as: > > #define MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, dir) \ > { \ > .num = ch_num, \ > .name = ch_name, \ > .dir = dir, \ > } > > #define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \ > MHI_EP_CHANNEL_CONFIG(ch_num, ch_name, DMA_FROM_DEVICE) > > > etc. Ok. > > > > + > > +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; > > + bool mhi_registered; > > Do we really need this variable ? Can't it be inferred from > the framework ? > Looks like yes. More below. > > +}; > > + > > +static int pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, > > + phys_addr_t *phys_ptr, void __iomem **virt, size_t size) > > +{ > > + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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 *virt_addr; > > + phys_addr_t phys_addr; > > + int ret; > > + > > + virt_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, size + offset); > > + if (!virt_addr) > > + return -ENOMEM; > > + > > + ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, phys_addr, pci_addr - offset, > > + size + offset); > > + if (ret) { > > + pci_epc_mem_free_addr(epc, phys_addr, virt_addr, size + offset); > > + > > + return ret; > > + } > > + > > + *phys_ptr = phys_addr + offset; > > + *virt = virt_addr + offset; > > + > > + return 0; > > +} > > + > > +static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, > > + phys_addr_t phys_addr, void __iomem *virt_addr, size_t size) > > +{ > > + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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, phys_addr - offset); > > + pci_epc_mem_free_addr(epc, phys_addr - offset, virt_addr - offset, size + offset); > > +} > > + > > +static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector) > > +{ > > + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_epf_mhi, mhi_cntrl); > > + struct pci_epf *epf = epf_mhi->epf; > > + struct pci_epc *epc = epf->epc; > > + > > + /* > > + * Vector is incremented by 1 here as the DWC core will decrement it before > > + * writing to iATU. > > This isn't OK. It is an API, you can't write code explicitly relying on > the underlying implementation. I assume the API is not well specified, > that's why we need these tricks ? > Well, this is not an API issue but rather an implementation detail of the DWC EP core driver. The DWC driver expects the interrupt vectors to be 1 based, so it decrements it before writing to the MSI address: [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/pci/controller/dwc/pcie-designware-ep.c#n537 > > + */ > > + 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 = container_of(mhi_cntrl, struct pci_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 % 0x1000; > > Explain what 0x1000 represents - make it a macro if that > helps > Ok. > > + int ret; > > + > > + mutex_lock(&epf_mhi->lock); > > + > > + tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset); > > + if (!tre_buf) { > > + mutex_unlock(&epf_mhi->lock); > > + return -ENOMEM; > > + } > > + > > + 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); > > + mutex_unlock(&epf_mhi->lock); > > I'd prefer a single goto label instead of repeating the code for every > branch taken but that's up to you. > Ok. > > + return ret; > > + } > > + > > + 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); > > + > > + mutex_unlock(&epf_mhi->lock); > > + > > + 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; > > + } > > + > > + epf_mhi->mhi_registered = true; > > I don't like this. It should be part of mhi_ep_register_controller(); > Hmm, I could use the "mhi_dev" pointer instead of a dedicated variable. > > + > > + return 0; > > +} > > + > > +static int pci_epf_mhi_link_down(struct pci_epf *epf) > > +{ > > + struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); > > + struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; > > + > > + if (epf_mhi->mhi_registered) { > > + mhi_ep_power_down(mhi_cntrl); > > + mhi_ep_unregister_controller(mhi_cntrl); > > + epf_mhi->mhi_registered = false; > > + } > > + > > + return 0; > > +} > > + > > +static int pci_epf_mhi_bme(struct pci_epf *epf) > > +{ > > + struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); > > + 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 && epf_mhi->mhi_registered) { > > + 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); > > + epf_mhi->mhi_registered = false; > > + } > > + } > > + > > + 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_wc(epf_mhi->mmio_phys, epf_mhi->mmio_size); > > ioremap_wc(). Why wc mappings ? Please explain. > I saw a reference to write combined access requirement for the MMIO region but couldn't verify it now. Will revert to non_wc mapping. - Mani
On 5/30/23 02:38, Manivannan Sadhasivam wrote: [...] >>> +static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, >>> + phys_addr_t phys_addr, void __iomem *virt_addr, size_t size) >>> +{ >>> + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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, phys_addr - offset); >>> + pci_epc_mem_free_addr(epc, phys_addr - offset, virt_addr - offset, size + offset); >>> +} >>> + >>> +static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector) >>> +{ >>> + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_epf_mhi, mhi_cntrl); >>> + struct pci_epf *epf = epf_mhi->epf; >>> + struct pci_epc *epc = epf->epc; >>> + >>> + /* >>> + * Vector is incremented by 1 here as the DWC core will decrement it before >>> + * writing to iATU. >> >> This isn't OK. It is an API, you can't write code explicitly relying on >> the underlying implementation. I assume the API is not well specified, >> that's why we need these tricks ? >> > > Well, this is not an API issue but rather an implementation detail of the DWC EP > core driver. The DWC driver expects the interrupt vectors to be 1 based, so it > decrements it before writing to the MSI address: > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/pci/controller/dwc/pcie-designware-ep.c#n537 Then the driver should be fixed so that this peculiarity is not visible at the user API level, resulting in a uniform usage of the API for all functions regardless of the controller being used.
On Tue, May 30, 2023 at 08:37:07AM +0900, Damien Le Moal wrote: > On 5/30/23 02:38, Manivannan Sadhasivam wrote: > [...] > >>> +static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, > >>> + phys_addr_t phys_addr, void __iomem *virt_addr, size_t size) > >>> +{ > >>> + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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, phys_addr - offset); > >>> + pci_epc_mem_free_addr(epc, phys_addr - offset, virt_addr - offset, size + offset); > >>> +} > >>> + > >>> +static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector) > >>> +{ > >>> + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_epf_mhi, mhi_cntrl); > >>> + struct pci_epf *epf = epf_mhi->epf; > >>> + struct pci_epc *epc = epf->epc; > >>> + > >>> + /* > >>> + * Vector is incremented by 1 here as the DWC core will decrement it before > >>> + * writing to iATU. > >> > >> This isn't OK. It is an API, you can't write code explicitly relying on > >> the underlying implementation. I assume the API is not well specified, > >> that's why we need these tricks ? > >> > > > > Well, this is not an API issue but rather an implementation detail of the DWC EP > > core driver. The DWC driver expects the interrupt vectors to be 1 based, so it > > decrements it before writing to the MSI address: > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/pci/controller/dwc/pcie-designware-ep.c#n537 > > Then the driver should be fixed so that this peculiarity is not visible at the > user API level, resulting in a uniform usage of the API for all functions > regardless of the controller being used. > Just checked with Kishon offline and confirmed that this is an API behavior. I also checked other drivers and they all doing the same. But unfortunately, this behavior is not documented in the API. Will add a patch for that. - Mani > -- > Damien Le Moal > Western Digital Research >
diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig index 9fd560886871..f5171b4fabbe 100644 --- a/drivers/pci/endpoint/functions/Kconfig +++ b/drivers/pci/endpoint/functions/Kconfig @@ -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. diff --git a/drivers/pci/endpoint/functions/Makefile b/drivers/pci/endpoint/functions/Makefile index 5c13001deaba..696473fce50e 100644 --- a/drivers/pci/endpoint/functions/Makefile +++ b/drivers/pci/endpoint/functions/Makefile @@ -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 diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c new file mode 100644 index 000000000000..df924fb10e4d --- /dev/null +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c @@ -0,0 +1,454 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCI EPF driver for MHI Endpoint devices + * + * Copyright (C) 2022 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 + +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_UL(ch_num, ch_name) \ + { \ + .num = ch_num, \ + .name = ch_name, \ + .dir = DMA_TO_DEVICE, \ + } + +#define MHI_EP_CHANNEL_CONFIG_DL(ch_num, ch_name) \ + { \ + .num = ch_num, \ + .name = ch_name, \ + .dir = 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; + bool mhi_registered; +}; + +static int pci_epf_mhi_alloc_map(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, + phys_addr_t *phys_ptr, void __iomem **virt, size_t size) +{ + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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 *virt_addr; + phys_addr_t phys_addr; + int ret; + + virt_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, size + offset); + if (!virt_addr) + return -ENOMEM; + + ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, phys_addr, pci_addr - offset, + size + offset); + if (ret) { + pci_epc_mem_free_addr(epc, phys_addr, virt_addr, size + offset); + + return ret; + } + + *phys_ptr = phys_addr + offset; + *virt = virt_addr + offset; + + return 0; +} + +static void pci_epf_mhi_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, + phys_addr_t phys_addr, void __iomem *virt_addr, size_t size) +{ + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_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, phys_addr - offset); + pci_epc_mem_free_addr(epc, phys_addr - offset, virt_addr - offset, size + offset); +} + +static void pci_epf_mhi_raise_irq(struct mhi_ep_cntrl *mhi_cntrl, u32 vector) +{ + struct pci_epf_mhi *epf_mhi = container_of(mhi_cntrl, struct pci_epf_mhi, mhi_cntrl); + struct pci_epf *epf = epf_mhi->epf; + struct pci_epc *epc = epf->epc; + + /* + * Vector is incremented by 1 here as the DWC core will decrement it before + * writing to iATU. + */ + 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 = container_of(mhi_cntrl, struct pci_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 % 0x1000; + int ret; + + mutex_lock(&epf_mhi->lock); + + tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset); + if (!tre_buf) { + mutex_unlock(&epf_mhi->lock); + return -ENOMEM; + } + + 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); + mutex_unlock(&epf_mhi->lock); + return ret; + } + + 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); + + mutex_unlock(&epf_mhi->lock); + + return 0; +} + +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 = container_of(mhi_cntrl, struct pci_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 % 0x1000; + int ret; + + mutex_lock(&epf_mhi->lock); + + tre_buf = pci_epc_mem_alloc_addr(epc, &tre_phys, size + offset); + if (!tre_buf) { + mutex_unlock(&epf_mhi->lock); + return -ENOMEM; + } + + 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); + mutex_unlock(&epf_mhi->lock); + return ret; + } + + 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); + + mutex_unlock(&epf_mhi->lock); + + return 0; +} + +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; + } + + epf_mhi->mhi_registered = true; + + return 0; +} + +static int pci_epf_mhi_link_down(struct pci_epf *epf) +{ + struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); + struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl; + + if (epf_mhi->mhi_registered) { + mhi_ep_power_down(mhi_cntrl); + mhi_ep_unregister_controller(mhi_cntrl); + epf_mhi->mhi_registered = false; + } + + return 0; +} + +static int pci_epf_mhi_bme(struct pci_epf *epf) +{ + struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf); + 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 && epf_mhi->mhi_registered) { + 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); + epf_mhi->mhi_registered = false; + } + } + + 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_wc(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 (epf_mhi->mhi_registered) { + mhi_ep_power_down(mhi_cntrl); + mhi_ep_unregister_controller(mhi_cntrl); + epf_mhi->mhi_registered = false; + } + + 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");