Skip to content

L
linux-davinci
An error occurred fetching the project authors.
Switch branch/tag
  1. 23 Jul, 2008 1 commit
  3. 22 Jul, 2008 1 commit
  5. 08 Jul, 2008 2 commits
  7. 17 Apr, 2008 2 commits
  9. 04 Mar, 2008 1 commit
  11. 06 Feb, 2008 2 commits
    • Dan Williams's avatar
      async_tx: replace 'int_en' with operation preparation flags · d4c56f97
      Dan Williams authored 
      Pass a full set of flags to drivers' per-operation 'prep' routines.
Currently the only flag passed is DMA_PREP_INTERRUPT.  The expectation is
that arch-specific async_tx_find_channel() implementations can exploit this
capability to find the best channel for an operation.
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
Acked-by: default avatarShannon Nelson <shannon.nelson@intel.com>
Reviewed-by: default avatarHaavard Skinnemoen <hskinnemoen@atmel.com>
      d4c56f97
    • Dan Williams's avatar
      async_tx: kill tx_set_src and tx_set_dest methods · 0036731c
      Dan Williams authored 
      The tx_set_src and tx_set_dest methods were originally implemented to allow
an array of addresses to be passed down from async_xor to the dmaengine
driver while minimizing stack overhead.  Removing these methods allows
drivers to have all transaction parameters available at 'prep' time, saves
two function pointers in struct dma_async_tx_descriptor, and reduces the
number of indirect branches..

A consequence of moving this data to the 'prep' routine is that
multi-source routines like async_xor need temporary storage to convert an
array of linear addresses into an array of dma addresses.  In order to keep
the same stack footprint of the previous implementation the input array is
reused as storage for the dma addresses.  This requires that
sizeof(dma_addr_t) be less than or equal to sizeof(void *).  As a
consequence CONFIG_DMADEVICES now depends on !CONFIG_HIGHMEM64G.  It also
requires that drivers be able to make descriptor resources available when
the 'prep' routine is polled.
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
Acked-by: default avatarShannon Nelson <shannon.nelson@intel.com>
      0036731c
  13. 18 Dec, 2007 2 commits
  15. 15 Nov, 2007 1 commit
  17. 18 Oct, 2007 5 commits
  19. 16 Oct, 2007 5 commits
  21. 27 Aug, 2007 1 commit
  23. 15 Aug, 2007 1 commit
    • Shannon Nelson's avatar
      [IOAT]: Remove redundant struct member to avoid descriptor cache miss · 54a09feb
      Shannon Nelson authored 
      The layout for struct ioat_desc_sw is non-optimal and causes an extra
cache hit for every descriptor processed.  By tightening up the struct
layout and removing one item, we pull in the fields that get used in
the speedpath and get a little better performance.


Before:
-------
struct ioat_desc_sw {
	struct ioat_dma_descriptor * hw;                 /*     0     8
*/
	struct list_head           node;                 /*     8    16
*/
	int                        tx_cnt;               /*    24     4
*/

	/* XXX 4 bytes hole, try to pack */

	dma_addr_t                 src;                  /*    32     8
*/
	__u32                      src_len;              /*    40     4
*/

	/* XXX 4 bytes hole, try to pack */

	dma_addr_t                 dst;                  /*    48     8
*/
	__u32                      dst_len;              /*    56     4
*/

	/* XXX 4 bytes hole, try to pack */

	/* --- cacheline 1 boundary (64 bytes) --- */
	struct dma_async_tx_descriptor async_tx;         /*    64   144
*/
	/* --- cacheline 3 boundary (192 bytes) was 16 bytes ago --- */

	/* size: 208, cachelines: 4 */
	/* sum members: 196, holes: 3, sum holes: 12 */
	/* last cacheline: 16 bytes */
};	/* definitions: 1 */


After:
------

struct ioat_desc_sw {
	struct ioat_dma_descriptor * hw;                 /*     0     8
*/
	struct list_head           node;                 /*     8    16
*/
	int                        tx_cnt;               /*    24     4
*/
	__u32                      len;                  /*    28     4
*/
	dma_addr_t                 src;                  /*    32     8
*/
	dma_addr_t                 dst;                  /*    40     8
*/
	struct dma_async_tx_descriptor async_tx;         /*    48   144
*/
	/* --- cacheline 3 boundary (192 bytes) --- */

	/* size: 192, cachelines: 3 */
};	/* definitions: 1 */
Signed-off-by: default avatarShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      54a09feb
  25. 13 Jul, 2007 3 commits
    • Dan Williams's avatar
      ioatdma: add the unisys "i/oat" pci vendor/device id · 3039f073
      Dan Williams authored 
      Cc: John Magolan <john.magolan@unisys.com>
Signed-off-by: default avatarShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
      3039f073
    • Dan Williams's avatar
      dmaengine: make clients responsible for managing channels · d379b01e
      Dan Williams authored 
      The current implementation assumes that a channel will only be used by one
client at a time.  In order to enable channel sharing the dmaengine core is
changed to a model where clients subscribe to channel-available-events.
Instead of tracking how many channels a client wants and how many it has
received the core just broadcasts the available channels and lets the
clients optionally take a reference.  The core learns about the clients'
needs at dma_event_callback time.

In support of multiple operation types, clients can specify a capability
mask to only be notified of channels that satisfy a certain set of
capabilities.

Changelog:
* removed DMA_TX_ARRAY_INIT, no longer needed
* dma_client_chan_free -> dma_chan_release: switch to global reference
  counting only at device unregistration time, before it was also happening
  at client unregistration time
* clients now return dma_state_client to dmaengine (ack, dup, nak)
* checkpatch.pl fixes
* fixup merge with git-ioat

Cc: Chris Leech <christopher.leech@intel.com>
Signed-off-by: default avatarShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      d379b01e
    • Dan Williams's avatar
      dmaengine: refactor dmaengine around dma_async_tx_descriptor · 7405f74b
      Dan Williams authored 
      The current dmaengine interface defines mutliple routines per operation,
i.e. dma_async_memcpy_buf_to_buf, dma_async_memcpy_buf_to_page etc.  Adding
more operation types (xor, crc, etc) to this model would result in an
unmanageable number of method permutations.

	Are we really going to add a set of hooks for each DMA engine
	whizbang feature?
		- Jeff Garzik

The descriptor creation process is refactored using the new common
dma_async_tx_descriptor structure.  Instead of per driver
do_<operation>_<dest>_to_<src> methods, drivers integrate
dma_async_tx_descriptor into their private software descriptor and then
define a 'prep' routine per operation.  The prep routine allocates a
descriptor and ensures that the tx_set_src, tx_set_dest, tx_submit routines
are valid.  Descriptor creation and submission becomes:

struct dma_device *dev;
struct dma_chan *chan;
struct dma_async_tx_descriptor *tx;

tx = dev->device_prep_dma_<operation>(chan, len, int_flag)
tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */)
tx->tx_set_dest(dma_addr_t, tx, index)
tx->tx_submit(tx)

In addition to the refactoring, dma_async_tx_descriptor also lays the
groundwork for definining cross-channel-operation dependencies, and a
callback facility for asynchronous notification of operation completion.

Changelog:
* drop dma mapping methods, suggested by Chris Leech
* fix ioat_dma_dependency_added, also caught by Andrew Morton
* fix dma_sync_wait, change from Andrew Morton
* uninline large functions, change from Andrew Morton
* add tx->callback = NULL to dmaengine calls to interoperate with async_tx
  calls
* hookup ioat_tx_submit
* convert channel capabilities to a 'cpumask_t like' bitmap
* removed DMA_TX_ARRAY_INIT, no longer needed
* checkpatch.pl fixes
* make set_src, set_dest, and tx_submit descriptor specific methods
* fixup git-ioat merge
* move group_list and phys to dma_async_tx_descriptor

Cc: Jeff Garzik <jeff@garzik.org>
Cc: Chris Leech <christopher.leech@intel.com>
Signed-off-by: default avatarShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      7405f74b
  27. 11 Jul, 2007 4 commits
  29. 28 Jun, 2007 1 commit
    • Randy Dunlap's avatar
      IOATDMA: fix section mismatches · 92504f79
      Randy Dunlap authored 
      Rename struct pci_driver data so that false section mismatch warnings won't
be produced.

Sam, ISTM that depending on variable names is the weakest & worst part of
modpost section checking.  Should __init_refok work here?  I got build
errors when I tried to use it, probably because the struct pci_driver probe
and remove methods are not marked "__init_refok".

WARNING: drivers/dma/ioatdma.o(.data+0x10): Section mismatch: reference to .init.text: (between 'ioat_pci_drv' and 'ioat_pci_tbl')
WARNING: drivers/dma/ioatdma.o(.data+0x14): Section mismatch: reference to .exit.text: (between 'ioat_pci_drv' and 'ioat_pci_tbl')
Signed-off-by: default avatarRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: default avatarChris Leech <christopher.leech@intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      92504f79
  31. 07 Dec, 2006 1 commit
  33. 10 Oct, 2006 1 commit
  35. 05 Oct, 2006 1 commit
    • David Howells's avatar
      IRQ: Maintain regs pointer globally rather than passing to IRQ handlers · 7d12e780
      David Howells authored 
      Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.
Signed-Off-By: default avatarDavid Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
      7d12e780
  37. 21 Jul, 2006 1 commit
  39. 04 Jul, 2006 2 commits
  41. 02 Jul, 2006 1 commit
  43. 26 Jun, 2006 1 commit