diff options
Diffstat (limited to 'drivers/misc/mic/host/mic_smpt.c')
| -rw-r--r-- | drivers/misc/mic/host/mic_smpt.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/drivers/misc/mic/host/mic_smpt.c b/drivers/misc/mic/host/mic_smpt.c new file mode 100644 index 000000000..c3f958580 --- /dev/null +++ b/drivers/misc/mic/host/mic_smpt.c @@ -0,0 +1,439 @@ +/* + * Intel MIC Platform Software Stack (MPSS) + * + * Copyright(c) 2013 Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + * + * Intel MIC Host driver. + * + */ +#include <linux/pci.h> + +#include "../common/mic_dev.h" +#include "mic_device.h" +#include "mic_smpt.h" + +static inline u64 mic_system_page_mask(struct mic_device *mdev) +{ + return (1ULL << mdev->smpt->info.page_shift) - 1ULL; +} + +static inline u8 mic_sys_addr_to_smpt(struct mic_device *mdev, dma_addr_t pa) +{ + return (pa - mdev->smpt->info.base) >> mdev->smpt->info.page_shift; +} + +static inline u64 mic_smpt_to_pa(struct mic_device *mdev, u8 index) +{ + return mdev->smpt->info.base + (index * mdev->smpt->info.page_size); +} + +static inline u64 mic_smpt_offset(struct mic_device *mdev, dma_addr_t pa) +{ + return pa & mic_system_page_mask(mdev); +} + +static inline u64 mic_smpt_align_low(struct mic_device *mdev, dma_addr_t pa) +{ + return ALIGN(pa - mic_system_page_mask(mdev), + mdev->smpt->info.page_size); +} + +static inline u64 mic_smpt_align_high(struct mic_device *mdev, dma_addr_t pa) +{ + return ALIGN(pa, mdev->smpt->info.page_size); +} + +/* Total Cumulative system memory accessible by MIC across all SMPT entries */ +static inline u64 mic_max_system_memory(struct mic_device *mdev) +{ + return mdev->smpt->info.num_reg * mdev->smpt->info.page_size; +} + +/* Maximum system memory address accessible by MIC */ +static inline u64 mic_max_system_addr(struct mic_device *mdev) +{ + return mdev->smpt->info.base + mic_max_system_memory(mdev) - 1ULL; +} + +/* Check if the DMA address is a MIC system memory address */ +static inline bool +mic_is_system_addr(struct mic_device *mdev, dma_addr_t pa) +{ + return pa >= mdev->smpt->info.base && pa <= mic_max_system_addr(mdev); +} + +/* Populate an SMPT entry and update the reference counts. */ +static void mic_add_smpt_entry(int spt, s64 *ref, u64 addr, + int entries, struct mic_device *mdev) +{ + struct mic_smpt_info *smpt_info = mdev->smpt; + int i; + + for (i = spt; i < spt + entries; i++, + addr += smpt_info->info.page_size) { + if (!smpt_info->entry[i].ref_count && + (smpt_info->entry[i].dma_addr != addr)) { + mdev->smpt_ops->set(mdev, addr, i); + smpt_info->entry[i].dma_addr = addr; + } + smpt_info->entry[i].ref_count += ref[i - spt]; + } +} + +/* + * Find an available MIC address in MIC SMPT address space + * for a given DMA address and size. + */ +static dma_addr_t mic_smpt_op(struct mic_device *mdev, u64 dma_addr, + int entries, s64 *ref, size_t size) +{ + int spt; + int ae = 0; + int i; + unsigned long flags; + dma_addr_t mic_addr = 0; + dma_addr_t addr = dma_addr; + struct mic_smpt_info *smpt_info = mdev->smpt; + + spin_lock_irqsave(&smpt_info->smpt_lock, flags); + + /* find existing entries */ + for (i = 0; i < smpt_info->info.num_reg; i++) { + if (smpt_info->entry[i].dma_addr == addr) { + ae++; + addr += smpt_info->info.page_size; + } else if (ae) /* cannot find contiguous entries */ + goto not_found; + + if (ae == entries) + goto found; + } + + /* find free entry */ + for (ae = 0, i = 0; i < smpt_info->info.num_reg; i++) { + ae = (smpt_info->entry[i].ref_count == 0) ? ae + 1 : 0; + if (ae == entries) + goto found; + } + +not_found: + spin_unlock_irqrestore(&smpt_info->smpt_lock, flags); + return mic_addr; + +found: + spt = i - entries + 1; + mic_addr = mic_smpt_to_pa(mdev, spt); + mic_add_smpt_entry(spt, ref, dma_addr, entries, mdev); + smpt_info->map_count++; + smpt_info->ref_count += (s64)size; + spin_unlock_irqrestore(&smpt_info->smpt_lock, flags); + return mic_addr; +} + +/* + * Returns number of smpt entries needed for dma_addr to dma_addr + size + * also returns the reference count array for each of those entries + * and the starting smpt address + */ +static int mic_get_smpt_ref_count(struct mic_device *mdev, dma_addr_t dma_addr, + size_t size, s64 *ref, u64 *smpt_start) +{ + u64 start = dma_addr; + u64 end = dma_addr + size; + int i = 0; + + while (start < end) { + ref[i++] = min(mic_smpt_align_high(mdev, start + 1), + end) - start; + start = mic_smpt_align_high(mdev, start + 1); + } + + if (smpt_start) + *smpt_start = mic_smpt_align_low(mdev, dma_addr); + + return i; +} + +/* + * mic_to_dma_addr - Converts a MIC address to a DMA address. + * + * @mdev: pointer to mic_device instance. + * @mic_addr: MIC address. + * + * returns a DMA address. + */ +dma_addr_t mic_to_dma_addr(struct mic_device *mdev, dma_addr_t mic_addr) +{ + struct mic_smpt_info *smpt_info = mdev->smpt; + int spt; + dma_addr_t dma_addr; + + if (!mic_is_system_addr(mdev, mic_addr)) { + dev_err(&mdev->pdev->dev, + "mic_addr is invalid. mic_addr = 0x%llx\n", mic_addr); + return -EINVAL; + } + spt = mic_sys_addr_to_smpt(mdev, mic_addr); + dma_addr = smpt_info->entry[spt].dma_addr + + mic_smpt_offset(mdev, mic_addr); + return dma_addr; +} + +/** + * mic_map - Maps a DMA address to a MIC physical address. + * + * @mdev: pointer to mic_device instance. + * @dma_addr: DMA address. + * @size: Size of the region to be mapped. + * + * This API converts the DMA address provided to a DMA address understood + * by MIC. Caller should check for errors by calling mic_map_error(..). + * + * returns DMA address as required by MIC. + */ +dma_addr_t mic_map(struct mic_device *mdev, dma_addr_t dma_addr, size_t size) +{ + dma_addr_t mic_addr = 0; + int num_entries; + s64 *ref; + u64 smpt_start; + + if (!size || size > mic_max_system_memory(mdev)) + return mic_addr; + + ref = kmalloc_array(mdev->smpt->info.num_reg, sizeof(s64), GFP_ATOMIC); + if (!ref) + return mic_addr; + + num_entries = mic_get_smpt_ref_count(mdev, dma_addr, size, + ref, &smpt_start); + + /* Set the smpt table appropriately and get 16G aligned mic address */ + mic_addr = mic_smpt_op(mdev, smpt_start, num_entries, ref, size); + + kfree(ref); + + /* + * If mic_addr is zero then its an error case + * since mic_addr can never be zero. + * else generate mic_addr by adding the 16G offset in dma_addr + */ + if (!mic_addr && MIC_FAMILY_X100 == mdev->family) { + dev_err(&mdev->pdev->dev, + "mic_map failed dma_addr 0x%llx size 0x%lx\n", + dma_addr, size); + return mic_addr; + } else { + return mic_addr + mic_smpt_offset(mdev, dma_addr); + } +} + +/** + * mic_unmap - Unmaps a MIC physical address. + * + * @mdev: pointer to mic_device instance. + * @mic_addr: MIC physical address. + * @size: Size of the region to be unmapped. + * + * This API unmaps the mappings created by mic_map(..). + * + * returns None. + */ +void mic_unmap(struct mic_device *mdev, dma_addr_t mic_addr, size_t size) +{ + struct mic_smpt_info *smpt_info = mdev->smpt; + s64 *ref; + int num_smpt; + int spt; + int i; + unsigned long flags; + + if (!size) + return; + + if (!mic_is_system_addr(mdev, mic_addr)) { + dev_err(&mdev->pdev->dev, + "invalid address: 0x%llx\n", mic_addr); + return; + } + + spt = mic_sys_addr_to_smpt(mdev, mic_addr); + ref = kmalloc_array(mdev->smpt->info.num_reg, sizeof(s64), GFP_ATOMIC); + if (!ref) + return; + + /* Get number of smpt entries to be mapped, ref count array */ + num_smpt = mic_get_smpt_ref_count(mdev, mic_addr, size, ref, NULL); + + spin_lock_irqsave(&smpt_info->smpt_lock, flags); + smpt_info->unmap_count++; + smpt_info->ref_count -= (s64)size; + + for (i = spt; i < spt + num_smpt; i++) { + smpt_info->entry[i].ref_count -= ref[i - spt]; + if (smpt_info->entry[i].ref_count < 0) + dev_warn(&mdev->pdev->dev, + "ref count for entry %d is negative\n", i); + } + spin_unlock_irqrestore(&smpt_info->smpt_lock, flags); + kfree(ref); +} + +/** + * mic_map_single - Maps a virtual address to a MIC physical address. + * + * @mdev: pointer to mic_device instance. + * @va: Kernel direct mapped virtual address. + * @size: Size of the region to be mapped. + * + * This API calls pci_map_single(..) for the direct mapped virtual address + * and then converts the DMA address provided to a DMA address understood + * by MIC. Caller should check for errors by calling mic_map_error(..). + * + * returns DMA address as required by MIC. + */ +dma_addr_t mic_map_single(struct mic_device *mdev, void *va, size_t size) +{ + dma_addr_t mic_addr = 0; + struct pci_dev *pdev = mdev->pdev; + dma_addr_t dma_addr = + pci_map_single(pdev, va, size, PCI_DMA_BIDIRECTIONAL); + + if (!pci_dma_mapping_error(pdev, dma_addr)) { + mic_addr = mic_map(mdev, dma_addr, size); + if (!mic_addr) { + dev_err(&mdev->pdev->dev, + "mic_map failed dma_addr 0x%llx size 0x%lx\n", + dma_addr, size); + pci_unmap_single(pdev, dma_addr, + size, PCI_DMA_BIDIRECTIONAL); + } + } + return mic_addr; +} + +/** + * mic_unmap_single - Unmaps a MIC physical address. + * + * @mdev: pointer to mic_device instance. + * @mic_addr: MIC physical address. + * @size: Size of the region to be unmapped. + * + * This API unmaps the mappings created by mic_map_single(..). + * + * returns None. + */ +void +mic_unmap_single(struct mic_device *mdev, dma_addr_t mic_addr, size_t size) +{ + struct pci_dev *pdev = mdev->pdev; + dma_addr_t dma_addr = mic_to_dma_addr(mdev, mic_addr); + mic_unmap(mdev, mic_addr, size); + pci_unmap_single(pdev, dma_addr, size, PCI_DMA_BIDIRECTIONAL); +} + +/** + * mic_smpt_init - Initialize MIC System Memory Page Tables. + * + * @mdev: pointer to mic_device instance. + * + * returns 0 for success and -errno for error. + */ +int mic_smpt_init(struct mic_device *mdev) +{ + int i, err = 0; + dma_addr_t dma_addr; + struct mic_smpt_info *smpt_info; + + mdev->smpt = kmalloc(sizeof(*mdev->smpt), GFP_KERNEL); + if (!mdev->smpt) + return -ENOMEM; + + smpt_info = mdev->smpt; + mdev->smpt_ops->init(mdev); + smpt_info->entry = kmalloc_array(smpt_info->info.num_reg, + sizeof(*smpt_info->entry), GFP_KERNEL); + if (!smpt_info->entry) { + err = -ENOMEM; + goto free_smpt; + } + spin_lock_init(&smpt_info->smpt_lock); + for (i = 0; i < smpt_info->info.num_reg; i++) { + dma_addr = i * smpt_info->info.page_size; + smpt_info->entry[i].dma_addr = dma_addr; + smpt_info->entry[i].ref_count = 0; + mdev->smpt_ops->set(mdev, dma_addr, i); + } + smpt_info->ref_count = 0; + smpt_info->map_count = 0; + smpt_info->unmap_count = 0; + return 0; +free_smpt: + kfree(smpt_info); + return err; +} + +/** + * mic_smpt_uninit - UnInitialize MIC System Memory Page Tables. + * + * @mdev: pointer to mic_device instance. + * + * returns None. + */ +void mic_smpt_uninit(struct mic_device *mdev) +{ + struct mic_smpt_info *smpt_info = mdev->smpt; + int i; + + dev_dbg(&mdev->pdev->dev, + "nodeid %d SMPT ref count %lld map %lld unmap %lld\n", + mdev->id, smpt_info->ref_count, + smpt_info->map_count, smpt_info->unmap_count); + + for (i = 0; i < smpt_info->info.num_reg; i++) { + dev_dbg(&mdev->pdev->dev, + "SMPT entry[%d] dma_addr = 0x%llx ref_count = %lld\n", + i, smpt_info->entry[i].dma_addr, + smpt_info->entry[i].ref_count); + if (smpt_info->entry[i].ref_count) + dev_warn(&mdev->pdev->dev, + "ref count for entry %d is not zero\n", i); + } + kfree(smpt_info->entry); + kfree(smpt_info); +} + +/** + * mic_smpt_restore - Restore MIC System Memory Page Tables. + * + * @mdev: pointer to mic_device instance. + * + * Restore the SMPT registers to values previously stored in the + * SW data structures. Some MIC steppings lose register state + * across resets and this API should be called for performing + * a restore operation if required. + * + * returns None. + */ +void mic_smpt_restore(struct mic_device *mdev) +{ + int i; + dma_addr_t dma_addr; + + for (i = 0; i < mdev->smpt->info.num_reg; i++) { + dma_addr = mdev->smpt->entry[i].dma_addr; + mdev->smpt_ops->set(mdev, dma_addr, i); + } +} |