mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-01 04:46:42 +07:00
bbea0b6e0d
Use the DMA_SLAVE capability of the DMAEngine API to copy/from a scatterlist into an arbitrary list of hardware address/length pairs. This allows a single DMA transaction to copy data from several different devices into a scatterlist at the same time. This also adds support to enable some controller-specific features such as external start and external pause for a DMA transaction. [dan.j.williams@intel.com: rebased on tx_list movement] Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Acked-by: Li Yang <leoli@freescale.com> Acked-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
137 lines
3.8 KiB
C
137 lines
3.8 KiB
C
/*
|
|
* Freescale MPC83XX / MPC85XX DMA Controller
|
|
*
|
|
* Copyright (c) 2009 Ira W. Snyder <iws@ovro.caltech.edu>
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public License
|
|
* version 2. This program is licensed "as is" without any warranty of any
|
|
* kind, whether express or implied.
|
|
*/
|
|
|
|
#ifndef __ARCH_POWERPC_ASM_FSLDMA_H__
|
|
#define __ARCH_POWERPC_ASM_FSLDMA_H__
|
|
|
|
#include <linux/dmaengine.h>
|
|
|
|
/*
|
|
* Definitions for the Freescale DMA controller's DMA_SLAVE implemention
|
|
*
|
|
* The Freescale DMA_SLAVE implementation was designed to handle many-to-many
|
|
* transfers. An example usage would be an accelerated copy between two
|
|
* scatterlists. Another example use would be an accelerated copy from
|
|
* multiple non-contiguous device buffers into a single scatterlist.
|
|
*
|
|
* A DMA_SLAVE transaction is defined by a struct fsl_dma_slave. This
|
|
* structure contains a list of hardware addresses that should be copied
|
|
* to/from the scatterlist passed into device_prep_slave_sg(). The structure
|
|
* also has some fields to enable hardware-specific features.
|
|
*/
|
|
|
|
/**
|
|
* struct fsl_dma_hw_addr
|
|
* @entry: linked list entry
|
|
* @address: the hardware address
|
|
* @length: length to transfer
|
|
*
|
|
* Holds a single physical hardware address / length pair for use
|
|
* with the DMAEngine DMA_SLAVE API.
|
|
*/
|
|
struct fsl_dma_hw_addr {
|
|
struct list_head entry;
|
|
|
|
dma_addr_t address;
|
|
size_t length;
|
|
};
|
|
|
|
/**
|
|
* struct fsl_dma_slave
|
|
* @addresses: a linked list of struct fsl_dma_hw_addr structures
|
|
* @request_count: value for DMA request count
|
|
* @src_loop_size: setup and enable constant source-address DMA transfers
|
|
* @dst_loop_size: setup and enable constant destination address DMA transfers
|
|
* @external_start: enable externally started DMA transfers
|
|
* @external_pause: enable externally paused DMA transfers
|
|
*
|
|
* Holds a list of address / length pairs for use with the DMAEngine
|
|
* DMA_SLAVE API implementation for the Freescale DMA controller.
|
|
*/
|
|
struct fsl_dma_slave {
|
|
|
|
/* List of hardware address/length pairs */
|
|
struct list_head addresses;
|
|
|
|
/* Support for extra controller features */
|
|
unsigned int request_count;
|
|
unsigned int src_loop_size;
|
|
unsigned int dst_loop_size;
|
|
bool external_start;
|
|
bool external_pause;
|
|
};
|
|
|
|
/**
|
|
* fsl_dma_slave_append - add an address/length pair to a struct fsl_dma_slave
|
|
* @slave: the &struct fsl_dma_slave to add to
|
|
* @address: the hardware address to add
|
|
* @length: the length of bytes to transfer from @address
|
|
*
|
|
* Add a hardware address/length pair to a struct fsl_dma_slave. Returns 0 on
|
|
* success, -ERRNO otherwise.
|
|
*/
|
|
static inline int fsl_dma_slave_append(struct fsl_dma_slave *slave,
|
|
dma_addr_t address, size_t length)
|
|
{
|
|
struct fsl_dma_hw_addr *addr;
|
|
|
|
addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
|
|
if (!addr)
|
|
return -ENOMEM;
|
|
|
|
INIT_LIST_HEAD(&addr->entry);
|
|
addr->address = address;
|
|
addr->length = length;
|
|
|
|
list_add_tail(&addr->entry, &slave->addresses);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* fsl_dma_slave_free - free a struct fsl_dma_slave
|
|
* @slave: the struct fsl_dma_slave to free
|
|
*
|
|
* Free a struct fsl_dma_slave and all associated address/length pairs
|
|
*/
|
|
static inline void fsl_dma_slave_free(struct fsl_dma_slave *slave)
|
|
{
|
|
struct fsl_dma_hw_addr *addr, *tmp;
|
|
|
|
if (slave) {
|
|
list_for_each_entry_safe(addr, tmp, &slave->addresses, entry) {
|
|
list_del(&addr->entry);
|
|
kfree(addr);
|
|
}
|
|
|
|
kfree(slave);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* fsl_dma_slave_alloc - allocate a struct fsl_dma_slave
|
|
* @gfp: the flags to pass to kmalloc when allocating this structure
|
|
*
|
|
* Allocate a struct fsl_dma_slave for use by the DMA_SLAVE API. Returns a new
|
|
* struct fsl_dma_slave on success, or NULL on failure.
|
|
*/
|
|
static inline struct fsl_dma_slave *fsl_dma_slave_alloc(gfp_t gfp)
|
|
{
|
|
struct fsl_dma_slave *slave;
|
|
|
|
slave = kzalloc(sizeof(*slave), gfp);
|
|
if (!slave)
|
|
return NULL;
|
|
|
|
INIT_LIST_HEAD(&slave->addresses);
|
|
return slave;
|
|
}
|
|
|
|
#endif /* __ARCH_POWERPC_ASM_FSLDMA_H__ */
|