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author | Dan Williams <dan.j.williams@intel.com> | 2007-01-02 20:52:26 (GMT) |
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committer | Dan Williams <dan.j.williams@intel.com> | 2007-07-13 15:06:18 (GMT) |
commit | c211092313b90f898dec61f35207fc282d1eadc3 (patch) | |
tree | 30df0c81f207d0babb3fe56a17419f37e71e973a /include/asm-arm/hardware | |
parent | f6dff381af01006ffae3c23cd2e07e30584de0ec (diff) | |
download | linux-fsl-qoriq-c211092313b90f898dec61f35207fc282d1eadc3.tar.xz |
dmaengine: driver for the iop32x, iop33x, and iop13xx raid engines
The Intel(R) IOP series of i/o processors integrate an Xscale core with
raid acceleration engines. The capabilities per platform are:
iop219:
(2) copy engines
iop321:
(2) copy engines
(1) xor and block fill engine
iop33x:
(2) copy and crc32c engines
(1) xor, xor zero sum, pq, pq zero sum, and block fill engine
iop34x (iop13xx):
(2) copy, crc32c, xor, xor zero sum, and block fill engines
(1) copy, crc32c, xor, xor zero sum, pq, pq zero sum, and block fill engine
The driver supports the features of the async_tx api:
* asynchronous notification of operation completion
* implicit (interupt triggered) handling of inter-channel transaction
dependencies
The driver adapts to the platform it is running by two methods.
1/ #include <asm/arch/adma.h> which defines the hardware specific
iop_chan_* and iop_desc_* routines as a series of static inline
functions
2/ The private platform data attached to the platform_device defines the
capabilities of the channels
20070626: Callbacks are run in a tasklet. Given the recent discussion on
LKML about killing tasklets in favor of workqueues I did a quick conversion
of the driver. Raid5 resync performance dropped from 50MB/s to 30MB/s, so
the tasklet implementation remains until a generic softirq interface is
available.
Changelog:
* fixed a slot allocation bug in do_iop13xx_adma_xor that caused too few
slots to be requested eventually leading to data corruption
* enabled the slot allocation routine to attempt to free slots before
returning -ENOMEM
* switched the cleanup routine to solely use the software chain and the
status register to determine if a descriptor is complete. This is
necessary to support other IOP engines that do not have status writeback
capability
* make the driver iop generic
* modified the allocation routines to understand allocating a group of
slots for a single operation
* added a null xor initialization operation for the xor only channel on
iop3xx
* support xor operations on buffers larger than the hardware maximum
* split the do_* routines into separate prep, src/dest set, submit stages
* added async_tx support (dependent operations initiation at cleanup time)
* simplified group handling
* added interrupt support (callbacks via tasklets)
* brought the pending depth inline with ioat (i.e. 4 descriptors)
* drop dma mapping methods, suggested by Chris Leech
* don't use inline in C files, Adrian Bunk
* remove static tasklet declarations
* make iop_adma_alloc_slots easier to read and remove chances for a
corrupted descriptor chain
* fix locking bug in iop_adma_alloc_chan_resources, Benjamin Herrenschmidt
* convert capabilities over to dma_cap_mask_t
* fixup sparse warnings
* add descriptor flush before iop_chan_enable
* checkpatch.pl fixes
* gpl v2 only correction
* move set_src, set_dest, submit to async_tx methods
* move group_list and phys to async_tx
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'include/asm-arm/hardware')
-rw-r--r-- | include/asm-arm/hardware/iop_adma.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/include/asm-arm/hardware/iop_adma.h b/include/asm-arm/hardware/iop_adma.h new file mode 100644 index 0000000..ca8e71f --- /dev/null +++ b/include/asm-arm/hardware/iop_adma.h @@ -0,0 +1,118 @@ +/* + * Copyright © 2006, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ +#ifndef IOP_ADMA_H +#define IOP_ADMA_H +#include <linux/types.h> +#include <linux/dmaengine.h> +#include <linux/interrupt.h> + +#define IOP_ADMA_SLOT_SIZE 32 +#define IOP_ADMA_THRESHOLD 4 + +/** + * struct iop_adma_device - internal representation of an ADMA device + * @pdev: Platform device + * @id: HW ADMA Device selector + * @dma_desc_pool: base of DMA descriptor region (DMA address) + * @dma_desc_pool_virt: base of DMA descriptor region (CPU address) + * @common: embedded struct dma_device + */ +struct iop_adma_device { + struct platform_device *pdev; + int id; + dma_addr_t dma_desc_pool; + void *dma_desc_pool_virt; + struct dma_device common; +}; + +/** + * struct iop_adma_chan - internal representation of an ADMA device + * @pending: allows batching of hardware operations + * @completed_cookie: identifier for the most recently completed operation + * @lock: serializes enqueue/dequeue operations to the slot pool + * @mmr_base: memory mapped register base + * @chain: device chain view of the descriptors + * @device: parent device + * @common: common dmaengine channel object members + * @last_used: place holder for allocation to continue from where it left off + * @all_slots: complete domain of slots usable by the channel + * @cleanup_watchdog: workaround missed interrupts on iop3xx + * @slots_allocated: records the actual size of the descriptor slot pool + * @irq_tasklet: bottom half where iop_adma_slot_cleanup runs + */ +struct iop_adma_chan { + int pending; + dma_cookie_t completed_cookie; + spinlock_t lock; /* protects the descriptor slot pool */ + void __iomem *mmr_base; + struct list_head chain; + struct iop_adma_device *device; + struct dma_chan common; + struct iop_adma_desc_slot *last_used; + struct list_head all_slots; + struct timer_list cleanup_watchdog; + int slots_allocated; + struct tasklet_struct irq_tasklet; +}; + +/** + * struct iop_adma_desc_slot - IOP-ADMA software descriptor + * @slot_node: node on the iop_adma_chan.all_slots list + * @chain_node: node on the op_adma_chan.chain list + * @hw_desc: virtual address of the hardware descriptor chain + * @phys: hardware address of the hardware descriptor chain + * @group_head: first operation in a transaction + * @slot_cnt: total slots used in an transaction (group of operations) + * @slots_per_op: number of slots per operation + * @idx: pool index + * @unmap_src_cnt: number of xor sources + * @unmap_len: transaction bytecount + * @async_tx: support for the async_tx api + * @group_list: list of slots that make up a multi-descriptor transaction + * for example transfer lengths larger than the supported hw max + * @xor_check_result: result of zero sum + * @crc32_result: result crc calculation + */ +struct iop_adma_desc_slot { + struct list_head slot_node; + struct list_head chain_node; + void *hw_desc; + struct iop_adma_desc_slot *group_head; + u16 slot_cnt; + u16 slots_per_op; + u16 idx; + u16 unmap_src_cnt; + size_t unmap_len; + struct dma_async_tx_descriptor async_tx; + union { + u32 *xor_check_result; + u32 *crc32_result; + }; +}; + +struct iop_adma_platform_data { + int hw_id; + dma_cap_mask_t cap_mask; + size_t pool_size; +}; + +#define to_iop_sw_desc(addr_hw_desc) \ + container_of(addr_hw_desc, struct iop_adma_desc_slot, hw_desc) +#define iop_hw_desc_slot_idx(hw_desc, idx) \ + ( (void *) (((unsigned long) hw_desc) + ((idx) << 5)) ) +#endif |