linux/drivers/misc/mic/host/mic_smpt.c

440 lines
12 KiB
C

/*
* 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);
}
}