diff options
Diffstat (limited to 'drivers/pci/endpoint/functions/pci-epf-mhi.c')
| -rw-r--r-- | drivers/pci/endpoint/functions/pci-epf-mhi.c | 716 |
1 files changed, 716 insertions, 0 deletions
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 0000000000..6dc918a8a0 --- /dev/null +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c @@ -0,0 +1,716 @@ +// 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/dmaengine.h> +#include <linux/mhi_ep.h> +#include <linux/module.h> +#include <linux/of_dma.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) + +/* Platform specific flags */ +#define MHI_EPF_USE_DMA BIT(0) + +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; + u32 flags; +}; + +#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, +}; + +static struct pci_epf_header sm8450_header = { + .vendorid = PCI_VENDOR_ID_QCOM, + .deviceid = 0x0306, + .baseclass_code = PCI_CLASS_OTHERS, + .interrupt_pin = PCI_INTERRUPT_INTA, +}; + +static const struct pci_epf_mhi_ep_info sm8450_info = { + .config = &mhi_v1_config, + .epf_header = &sm8450_header, + .bar_num = BAR_0, + .epf_flags = PCI_BASE_ADDRESS_MEM_TYPE_32, + .msi_count = 32, + .mru = 0x8000, + .flags = MHI_EPF_USE_DMA, +}; + +struct pci_epf_mhi { + const struct pci_epc_features *epc_features; + 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; + struct dma_chan *dma_chan_tx; + struct dma_chan *dma_chan_rx; + u32 mmio_size; + int irq; +}; + +static size_t get_align_offset(struct pci_epf_mhi *epf_mhi, u64 addr) +{ + return addr & (epf_mhi->epc_features->align -1); +} + +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 offset, 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; + 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 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); + size_t offset = get_align_offset(epf_mhi, pci_addr); + + return __pci_epf_mhi_alloc_map(mhi_cntrl, pci_addr, paddr, vaddr, + offset, size); +} + +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 offset, + 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; + + 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_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); + size_t offset = get_align_offset(epf_mhi, pci_addr); + + __pci_epf_mhi_unmap_free(mhi_cntrl, pci_addr, paddr, vaddr, offset, + size); +} + +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 vectors but the API expects the vector + * number to start from 1, 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_iatu_read(struct mhi_ep_cntrl *mhi_cntrl, + struct mhi_ep_buf_info *buf_info) +{ + struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); + size_t offset = get_align_offset(epf_mhi, buf_info->host_addr); + void __iomem *tre_buf; + phys_addr_t tre_phys; + int ret; + + mutex_lock(&epf_mhi->lock); + + ret = __pci_epf_mhi_alloc_map(mhi_cntrl, buf_info->host_addr, &tre_phys, + &tre_buf, offset, buf_info->size); + if (ret) { + mutex_unlock(&epf_mhi->lock); + return ret; + } + + memcpy_fromio(buf_info->dev_addr, tre_buf, buf_info->size); + + __pci_epf_mhi_unmap_free(mhi_cntrl, buf_info->host_addr, tre_phys, + tre_buf, offset, buf_info->size); + + mutex_unlock(&epf_mhi->lock); + + return 0; +} + +static int pci_epf_mhi_iatu_write(struct mhi_ep_cntrl *mhi_cntrl, + struct mhi_ep_buf_info *buf_info) +{ + struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); + size_t offset = get_align_offset(epf_mhi, buf_info->host_addr); + void __iomem *tre_buf; + phys_addr_t tre_phys; + int ret; + + mutex_lock(&epf_mhi->lock); + + ret = __pci_epf_mhi_alloc_map(mhi_cntrl, buf_info->host_addr, &tre_phys, + &tre_buf, offset, buf_info->size); + if (ret) { + mutex_unlock(&epf_mhi->lock); + return ret; + } + + memcpy_toio(tre_buf, buf_info->dev_addr, buf_info->size); + + __pci_epf_mhi_unmap_free(mhi_cntrl, buf_info->host_addr, tre_phys, + tre_buf, offset, buf_info->size); + + mutex_unlock(&epf_mhi->lock); + + return 0; +} + +static void pci_epf_mhi_dma_callback(void *param) +{ + complete(param); +} + +static int pci_epf_mhi_edma_read(struct mhi_ep_cntrl *mhi_cntrl, + struct mhi_ep_buf_info *buf_info) +{ + struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); + struct device *dma_dev = epf_mhi->epf->epc->dev.parent; + struct dma_chan *chan = epf_mhi->dma_chan_rx; + struct device *dev = &epf_mhi->epf->dev; + DECLARE_COMPLETION_ONSTACK(complete); + struct dma_async_tx_descriptor *desc; + struct dma_slave_config config = {}; + dma_cookie_t cookie; + dma_addr_t dst_addr; + int ret; + + if (buf_info->size < SZ_4K) + return pci_epf_mhi_iatu_read(mhi_cntrl, buf_info); + + mutex_lock(&epf_mhi->lock); + + config.direction = DMA_DEV_TO_MEM; + config.src_addr = buf_info->host_addr; + + ret = dmaengine_slave_config(chan, &config); + if (ret) { + dev_err(dev, "Failed to configure DMA channel\n"); + goto err_unlock; + } + + dst_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size, + DMA_FROM_DEVICE); + ret = dma_mapping_error(dma_dev, dst_addr); + if (ret) { + dev_err(dev, "Failed to map remote memory\n"); + goto err_unlock; + } + + desc = dmaengine_prep_slave_single(chan, dst_addr, buf_info->size, + DMA_DEV_TO_MEM, + DMA_CTRL_ACK | DMA_PREP_INTERRUPT); + if (!desc) { + dev_err(dev, "Failed to prepare DMA\n"); + ret = -EIO; + goto err_unmap; + } + + desc->callback = pci_epf_mhi_dma_callback; + desc->callback_param = &complete; + + cookie = dmaengine_submit(desc); + ret = dma_submit_error(cookie); + if (ret) { + dev_err(dev, "Failed to do DMA submit\n"); + goto err_unmap; + } + + dma_async_issue_pending(chan); + ret = wait_for_completion_timeout(&complete, msecs_to_jiffies(1000)); + if (!ret) { + dev_err(dev, "DMA transfer timeout\n"); + dmaengine_terminate_sync(chan); + ret = -ETIMEDOUT; + } + +err_unmap: + dma_unmap_single(dma_dev, dst_addr, buf_info->size, DMA_FROM_DEVICE); +err_unlock: + mutex_unlock(&epf_mhi->lock); + + return ret; +} + +static int pci_epf_mhi_edma_write(struct mhi_ep_cntrl *mhi_cntrl, + struct mhi_ep_buf_info *buf_info) +{ + struct pci_epf_mhi *epf_mhi = to_epf_mhi(mhi_cntrl); + struct device *dma_dev = epf_mhi->epf->epc->dev.parent; + struct dma_chan *chan = epf_mhi->dma_chan_tx; + struct device *dev = &epf_mhi->epf->dev; + DECLARE_COMPLETION_ONSTACK(complete); + struct dma_async_tx_descriptor *desc; + struct dma_slave_config config = {}; + dma_cookie_t cookie; + dma_addr_t src_addr; + int ret; + + if (buf_info->size < SZ_4K) + return pci_epf_mhi_iatu_write(mhi_cntrl, buf_info); + + mutex_lock(&epf_mhi->lock); + + config.direction = DMA_MEM_TO_DEV; + config.dst_addr = buf_info->host_addr; + + ret = dmaengine_slave_config(chan, &config); + if (ret) { + dev_err(dev, "Failed to configure DMA channel\n"); + goto err_unlock; + } + + src_addr = dma_map_single(dma_dev, buf_info->dev_addr, buf_info->size, + DMA_TO_DEVICE); + ret = dma_mapping_error(dma_dev, src_addr); + if (ret) { + dev_err(dev, "Failed to map remote memory\n"); + goto err_unlock; + } + + desc = dmaengine_prep_slave_single(chan, src_addr, buf_info->size, + DMA_MEM_TO_DEV, + DMA_CTRL_ACK | DMA_PREP_INTERRUPT); + if (!desc) { + dev_err(dev, "Failed to prepare DMA\n"); + ret = -EIO; + goto err_unmap; + } + + desc->callback = pci_epf_mhi_dma_callback; + desc->callback_param = &complete; + + cookie = dmaengine_submit(desc); + ret = dma_submit_error(cookie); + if (ret) { + dev_err(dev, "Failed to do DMA submit\n"); + goto err_unmap; + } + + dma_async_issue_pending(chan); + ret = wait_for_completion_timeout(&complete, msecs_to_jiffies(1000)); + if (!ret) { + dev_err(dev, "DMA transfer timeout\n"); + dmaengine_terminate_sync(chan); + ret = -ETIMEDOUT; + } + +err_unmap: + dma_unmap_single(dma_dev, src_addr, buf_info->size, DMA_TO_DEVICE); +err_unlock: + mutex_unlock(&epf_mhi->lock); + + return ret; +} + +struct epf_dma_filter { + struct device *dev; + u32 dma_mask; +}; + +static bool pci_epf_mhi_filter(struct dma_chan *chan, void *node) +{ + struct epf_dma_filter *filter = node; + struct dma_slave_caps caps; + + memset(&caps, 0, sizeof(caps)); + dma_get_slave_caps(chan, &caps); + + return chan->device->dev == filter->dev && filter->dma_mask & + caps.directions; +} + +static int pci_epf_mhi_dma_init(struct pci_epf_mhi *epf_mhi) +{ + struct device *dma_dev = epf_mhi->epf->epc->dev.parent; + struct device *dev = &epf_mhi->epf->dev; + struct epf_dma_filter filter; + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + filter.dev = dma_dev; + filter.dma_mask = BIT(DMA_MEM_TO_DEV); + epf_mhi->dma_chan_tx = dma_request_channel(mask, pci_epf_mhi_filter, + &filter); + if (IS_ERR_OR_NULL(epf_mhi->dma_chan_tx)) { + dev_err(dev, "Failed to request tx channel\n"); + return -ENODEV; + } + + filter.dma_mask = BIT(DMA_DEV_TO_MEM); + epf_mhi->dma_chan_rx = dma_request_channel(mask, pci_epf_mhi_filter, + &filter); + if (IS_ERR_OR_NULL(epf_mhi->dma_chan_rx)) { + dev_err(dev, "Failed to request rx channel\n"); + dma_release_channel(epf_mhi->dma_chan_tx); + epf_mhi->dma_chan_tx = NULL; + return -ENODEV; + } + + return 0; +} + +static void pci_epf_mhi_dma_deinit(struct pci_epf_mhi *epf_mhi) +{ + dma_release_channel(epf_mhi->dma_chan_tx); + dma_release_channel(epf_mhi->dma_chan_rx); + epf_mhi->dma_chan_tx = NULL; + epf_mhi->dma_chan_rx = NULL; +} + +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; + } + + epf_mhi->epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no); + if (!epf_mhi->epc_features) + return -ENODATA; + + 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; + + if (info->flags & MHI_EPF_USE_DMA) { + ret = pci_epf_mhi_dma_init(epf_mhi); + if (ret) { + dev_err(dev, "Failed to initialize DMA: %d\n", ret); + return 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; + if (info->flags & MHI_EPF_USE_DMA) { + mhi_cntrl->read_from_host = pci_epf_mhi_edma_read; + mhi_cntrl->write_to_host = pci_epf_mhi_edma_write; + } else { + mhi_cntrl->read_from_host = pci_epf_mhi_iatu_read; + mhi_cntrl->write_to_host = pci_epf_mhi_iatu_write; + } + + /* 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); + if (info->flags & MHI_EPF_USE_DMA) + pci_epf_mhi_dma_deinit(epf_mhi); + 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); + if (info->flags & MHI_EPF_USE_DMA) + pci_epf_mhi_dma_deinit(epf_mhi); + 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); + if (info->flags & MHI_EPF_USE_DMA) + pci_epf_mhi_dma_deinit(epf_mhi); + 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 resource *res; + int ret; + + /* 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 (!epf_mhi->mmio) + return -ENOMEM; + + ret = platform_get_irq_byname(pdev, "doorbell"); + if (ret < 0) { + 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); + if (info->flags & MHI_EPF_USE_DMA) + pci_epf_mhi_dma_deinit(epf_mhi); + 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 }, + { .name = "sm8450", .driver_data = (kernel_ulong_t)&sm8450_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"); |