alistair23-linux/drivers/dma/ioat/dma.h
Dave Jiang c997e30e7f dmaengine: IOATDMA: revise channel reset workaround on CB3.3 platforms
Previously we unloaded the interrupts and reloaded in order to work around
a channel reset bug that cleared the MSIX table. This approach just isn't
practical when a reset needs to happen in the error handler that just
happens to be running in interrupt context (bottom half). It looks like we
can work around the hardware issue by just storing a shadow copy of the
MSIX table and restore it after reset.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-03-11 07:55:08 +05:30

419 lines
12 KiB
C

/*
* Copyright(c) 2004 - 2009 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* 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.
*/
#ifndef IOATDMA_H
#define IOATDMA_H
#include <linux/dmaengine.h>
#include <linux/init.h>
#include <linux/dmapool.h>
#include <linux/cache.h>
#include <linux/pci_ids.h>
#include <linux/circ_buf.h>
#include <linux/interrupt.h>
#include "registers.h"
#include "hw.h"
#define IOAT_DMA_VERSION "4.00"
#define IOAT_DMA_DCA_ANY_CPU ~0
#define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, dma_dev)
#define to_dev(ioat_chan) (&(ioat_chan)->ioat_dma->pdev->dev)
#define to_pdev(ioat_chan) ((ioat_chan)->ioat_dma->pdev)
#define chan_num(ch) ((int)((ch)->reg_base - (ch)->ioat_dma->reg_base) / 0x80)
/* ioat hardware assumes at least two sources for raid operations */
#define src_cnt_to_sw(x) ((x) + 2)
#define src_cnt_to_hw(x) ((x) - 2)
#define ndest_to_sw(x) ((x) + 1)
#define ndest_to_hw(x) ((x) - 1)
#define src16_cnt_to_sw(x) ((x) + 9)
#define src16_cnt_to_hw(x) ((x) - 9)
/*
* workaround for IOAT ver.3.0 null descriptor issue
* (channel returns error when size is 0)
*/
#define NULL_DESC_BUFFER_SIZE 1
enum ioat_irq_mode {
IOAT_NOIRQ = 0,
IOAT_MSIX,
IOAT_MSI,
IOAT_INTX
};
/**
* struct ioatdma_device - internal representation of a IOAT device
* @pdev: PCI-Express device
* @reg_base: MMIO register space base address
* @completion_pool: DMA buffers for completion ops
* @sed_hw_pool: DMA super descriptor pools
* @dma_dev: embedded struct dma_device
* @version: version of ioatdma device
* @msix_entries: irq handlers
* @idx: per channel data
* @dca: direct cache access context
* @irq_mode: interrupt mode (INTX, MSI, MSIX)
* @cap: read DMA capabilities register
*/
struct ioatdma_device {
struct pci_dev *pdev;
void __iomem *reg_base;
struct dma_pool *completion_pool;
#define MAX_SED_POOLS 5
struct dma_pool *sed_hw_pool[MAX_SED_POOLS];
struct dma_device dma_dev;
u8 version;
#define IOAT_MAX_CHANS 4
struct msix_entry msix_entries[IOAT_MAX_CHANS];
struct ioatdma_chan *idx[IOAT_MAX_CHANS];
struct dca_provider *dca;
enum ioat_irq_mode irq_mode;
u32 cap;
/* shadow version for CB3.3 chan reset errata workaround */
u64 msixtba0;
u64 msixdata0;
u32 msixpba;
};
struct ioat_descs {
void *virt;
dma_addr_t hw;
};
struct ioatdma_chan {
struct dma_chan dma_chan;
void __iomem *reg_base;
dma_addr_t last_completion;
spinlock_t cleanup_lock;
unsigned long state;
#define IOAT_CHAN_DOWN 0
#define IOAT_COMPLETION_ACK 1
#define IOAT_RESET_PENDING 2
#define IOAT_KOBJ_INIT_FAIL 3
#define IOAT_RUN 5
#define IOAT_CHAN_ACTIVE 6
struct timer_list timer;
#define COMPLETION_TIMEOUT msecs_to_jiffies(100)
#define IDLE_TIMEOUT msecs_to_jiffies(2000)
#define RESET_DELAY msecs_to_jiffies(100)
struct ioatdma_device *ioat_dma;
dma_addr_t completion_dma;
u64 *completion;
struct tasklet_struct cleanup_task;
struct kobject kobj;
/* ioat v2 / v3 channel attributes
* @xfercap_log; log2 of channel max transfer length (for fast division)
* @head: allocated index
* @issued: hardware notification point
* @tail: cleanup index
* @dmacount: identical to 'head' except for occasionally resetting to zero
* @alloc_order: log2 of the number of allocated descriptors
* @produce: number of descriptors to produce at submit time
* @ring: software ring buffer implementation of hardware ring
* @prep_lock: serializes descriptor preparation (producers)
*/
size_t xfercap_log;
u16 head;
u16 issued;
u16 tail;
u16 dmacount;
u16 alloc_order;
u16 produce;
struct ioat_ring_ent **ring;
spinlock_t prep_lock;
struct ioat_descs descs[2];
int desc_chunks;
};
struct ioat_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct dma_chan *, char *);
};
/**
* struct ioat_sed_ent - wrapper around super extended hardware descriptor
* @hw: hardware SED
* @dma: dma address for the SED
* @parent: point to the dma descriptor that's the parent
* @hw_pool: descriptor pool index
*/
struct ioat_sed_ent {
struct ioat_sed_raw_descriptor *hw;
dma_addr_t dma;
struct ioat_ring_ent *parent;
unsigned int hw_pool;
};
/**
* struct ioat_ring_ent - wrapper around hardware descriptor
* @hw: hardware DMA descriptor (for memcpy)
* @xor: hardware xor descriptor
* @xor_ex: hardware xor extension descriptor
* @pq: hardware pq descriptor
* @pq_ex: hardware pq extension descriptor
* @pqu: hardware pq update descriptor
* @raw: hardware raw (un-typed) descriptor
* @txd: the generic software descriptor for all engines
* @len: total transaction length for unmap
* @result: asynchronous result of validate operations
* @id: identifier for debug
* @sed: pointer to super extended descriptor sw desc
*/
struct ioat_ring_ent {
union {
struct ioat_dma_descriptor *hw;
struct ioat_xor_descriptor *xor;
struct ioat_xor_ext_descriptor *xor_ex;
struct ioat_pq_descriptor *pq;
struct ioat_pq_ext_descriptor *pq_ex;
struct ioat_pq_update_descriptor *pqu;
struct ioat_raw_descriptor *raw;
};
size_t len;
struct dma_async_tx_descriptor txd;
enum sum_check_flags *result;
#ifdef DEBUG
int id;
#endif
struct ioat_sed_ent *sed;
};
extern const struct sysfs_ops ioat_sysfs_ops;
extern struct ioat_sysfs_entry ioat_version_attr;
extern struct ioat_sysfs_entry ioat_cap_attr;
extern int ioat_pending_level;
extern int ioat_ring_alloc_order;
extern struct kobj_type ioat_ktype;
extern struct kmem_cache *ioat_cache;
extern int ioat_ring_max_alloc_order;
extern struct kmem_cache *ioat_sed_cache;
static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)
{
return container_of(c, struct ioatdma_chan, dma_chan);
}
/* wrapper around hardware descriptor format + additional software fields */
#ifdef DEBUG
#define set_desc_id(desc, i) ((desc)->id = (i))
#define desc_id(desc) ((desc)->id)
#else
#define set_desc_id(desc, i)
#define desc_id(desc) (0)
#endif
static inline void
__dump_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_dma_descriptor *hw,
struct dma_async_tx_descriptor *tx, int id)
{
struct device *dev = to_dev(ioat_chan);
dev_dbg(dev, "desc[%d]: (%#llx->%#llx) cookie: %d flags: %#x"
" ctl: %#10.8x (op: %#x int_en: %d compl: %d)\n", id,
(unsigned long long) tx->phys,
(unsigned long long) hw->next, tx->cookie, tx->flags,
hw->ctl, hw->ctl_f.op, hw->ctl_f.int_en, hw->ctl_f.compl_write);
}
#define dump_desc_dbg(c, d) \
({ if (d) __dump_desc_dbg(c, d->hw, &d->txd, desc_id(d)); 0; })
static inline struct ioatdma_chan *
ioat_chan_by_index(struct ioatdma_device *ioat_dma, int index)
{
return ioat_dma->idx[index];
}
static inline u64 ioat_chansts(struct ioatdma_chan *ioat_chan)
{
return readq(ioat_chan->reg_base + IOAT_CHANSTS_OFFSET);
}
static inline u64 ioat_chansts_to_addr(u64 status)
{
return status & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
}
static inline u32 ioat_chanerr(struct ioatdma_chan *ioat_chan)
{
return readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
}
static inline void ioat_suspend(struct ioatdma_chan *ioat_chan)
{
u8 ver = ioat_chan->ioat_dma->version;
writeb(IOAT_CHANCMD_SUSPEND,
ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
}
static inline void ioat_reset(struct ioatdma_chan *ioat_chan)
{
u8 ver = ioat_chan->ioat_dma->version;
writeb(IOAT_CHANCMD_RESET,
ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
}
static inline bool ioat_reset_pending(struct ioatdma_chan *ioat_chan)
{
u8 ver = ioat_chan->ioat_dma->version;
u8 cmd;
cmd = readb(ioat_chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
}
static inline bool is_ioat_active(unsigned long status)
{
return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_ACTIVE);
}
static inline bool is_ioat_idle(unsigned long status)
{
return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_DONE);
}
static inline bool is_ioat_halted(unsigned long status)
{
return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_HALTED);
}
static inline bool is_ioat_suspended(unsigned long status)
{
return ((status & IOAT_CHANSTS_STATUS) == IOAT_CHANSTS_SUSPENDED);
}
/* channel was fatally programmed */
static inline bool is_ioat_bug(unsigned long err)
{
return !!err;
}
#define IOAT_MAX_ORDER 16
#define IOAT_MAX_DESCS 65536
#define IOAT_DESCS_PER_2M 32768
static inline u32 ioat_ring_size(struct ioatdma_chan *ioat_chan)
{
return 1 << ioat_chan->alloc_order;
}
/* count of descriptors in flight with the engine */
static inline u16 ioat_ring_active(struct ioatdma_chan *ioat_chan)
{
return CIRC_CNT(ioat_chan->head, ioat_chan->tail,
ioat_ring_size(ioat_chan));
}
/* count of descriptors pending submission to hardware */
static inline u16 ioat_ring_pending(struct ioatdma_chan *ioat_chan)
{
return CIRC_CNT(ioat_chan->head, ioat_chan->issued,
ioat_ring_size(ioat_chan));
}
static inline u32 ioat_ring_space(struct ioatdma_chan *ioat_chan)
{
return ioat_ring_size(ioat_chan) - ioat_ring_active(ioat_chan);
}
static inline u16
ioat_xferlen_to_descs(struct ioatdma_chan *ioat_chan, size_t len)
{
u16 num_descs = len >> ioat_chan->xfercap_log;
num_descs += !!(len & ((1 << ioat_chan->xfercap_log) - 1));
return num_descs;
}
static inline struct ioat_ring_ent *
ioat_get_ring_ent(struct ioatdma_chan *ioat_chan, u16 idx)
{
return ioat_chan->ring[idx & (ioat_ring_size(ioat_chan) - 1)];
}
static inline void
ioat_set_chainaddr(struct ioatdma_chan *ioat_chan, u64 addr)
{
writel(addr & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
writel(addr >> 32,
ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
}
/* IOAT Prep functions */
struct dma_async_tx_descriptor *
ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
dma_addr_t dma_src, size_t len, unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
unsigned int src_cnt, size_t len, unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
unsigned int src_cnt, size_t len,
enum sum_check_flags *result, unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
unsigned int src_cnt, const unsigned char *scf, size_t len,
unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
unsigned int src_cnt, const unsigned char *scf, size_t len,
enum sum_check_flags *pqres, unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
unsigned int src_cnt, size_t len, unsigned long flags);
struct dma_async_tx_descriptor *
ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
unsigned int src_cnt, size_t len,
enum sum_check_flags *result, unsigned long flags);
/* IOAT Operation functions */
irqreturn_t ioat_dma_do_interrupt(int irq, void *data);
irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data);
struct ioat_ring_ent **
ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags);
void ioat_start_null_desc(struct ioatdma_chan *ioat_chan);
void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan);
int ioat_reset_hw(struct ioatdma_chan *ioat_chan);
enum dma_status
ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
struct dma_tx_state *txstate);
void ioat_cleanup_event(unsigned long data);
void ioat_timer_event(unsigned long data);
int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs);
void ioat_issue_pending(struct dma_chan *chan);
void ioat_timer_event(unsigned long data);
/* IOAT Init functions */
bool is_bwd_ioat(struct pci_dev *pdev);
struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase);
void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type);
void ioat_kobject_del(struct ioatdma_device *ioat_dma);
int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma);
void ioat_stop(struct ioatdma_chan *ioat_chan);
#endif /* IOATDMA_H */