[PATCH v4 0/3] Add support for AMD PTDMA controller driver

From: Sanjay R Mehta
Date: Tue Apr 28 2020 - 17:14:18 EST


From: Sanjay R Mehta <sanju.mehta@xxxxxxx>

This patch series adds support for AMD PTDMA controller which
performs high bandwidth memory-to-memory and IO copy operation and
performs DMA transfer through queue based descriptor management.

AMD Processor has multiple ptdma device instances and each controller
has single queue. The driver also adds support for for multiple PTDMA
instances, each device will get an unique identifier and uniquely
named resources.

v4:
- modified DMA channel and descriptor management using virt-dma layer
instead of list based management.
- return only status of the cookie from pt_tx_status
- copyright year changed from 2019 to 2020
- removed dummy code for suspend & resume
- used bitmask and genmask

v3:
- Fixed the sparse warnings.

v2:
- Added controller description in cover letter
- Removed "default m" from Kconfig
- Replaced low_address() and high_address() functions with kernel
API's lower_32_bits & upper_32_bits().
- Removed the BH handler function pt_core_irq_bh() and instead
handling transaction in irq handler itself.
- Moved presetting of command queue registers into new function
"init_cmdq_regs()"
- Removed the kernel thread dependency to submit transaction.
- Increased the hardware command queue size to 32 and adding it
as a module parameter.
- Removed backlog command queue handling mechanism.
- Removed software command queue handling and instead submitting
transaction command directly to
hardware command queue.
- Added tasklet structure variable in "struct pt_device".
This is used to invoke pt_do_cmd_complete() upon receiving interrupt
for command completion.
- pt_core_perform_passthru() function parameters are modified and it is
now used to submit command directly to hardware from dmaengine framew
- Removed below structures, enums, macros and functions, as these value
constants. Making command submission simple,
- Removed "union pt_function" and several macros like PT_VERSION,
PT_BYTESWAP, PT_CMD_* etc..
- enum pt_passthru_bitwise, enum pt_passthru_byteswap, enum pt_memty
struct pt_dma_info, struct pt_data, struct pt_mem, struct pt_passt
struct pt_op,

Links of the review comments for v4:
1. https://lkml.org/lkml/2020/1/24/12
2. https://lkml.org/lkml/2020/1/24/17

Links of the review comments for v2:
1. https://lkml.org/lkml/2019/12/27/630
2. https://lkml.org/lkml/2020/1/3/23
3. https://lkml.org/lkml/2020/1/3/314
4. https://lkml.org/lkml/2020/1/10/100

Links of the review comments for v1:
1. https://lkml.org/lkml/2019/9/24/490
2. https://lkml.org/lkml/2019/9/24/399
3. https://lkml.org/lkml/2019/9/24/862
4. https://lkml.org/lkml/2019/9/24/122

Sanjay R Mehta (3):
dmaengine: ptdma: Initial driver for the AMD PTDMA controller
dmaengine: ptdma: register PTDMA controller as a DMA resource
dmaengine: ptdma: Add debugfs entries for PTDMA information

MAINTAINERS | 6 +
drivers/dma/Kconfig | 2 +
drivers/dma/Makefile | 1 +
drivers/dma/ptdma/Kconfig | 13 +
drivers/dma/ptdma/Makefile | 12 +
drivers/dma/ptdma/ptdma-debugfs.c | 237 ++++++++++++++
drivers/dma/ptdma/ptdma-dev.c | 460 +++++++++++++++++++++++++++
drivers/dma/ptdma/ptdma-dmaengine.c | 597 ++++++++++++++++++++++++++++++++++++
drivers/dma/ptdma/ptdma-pci.c | 253 +++++++++++++++
drivers/dma/ptdma/ptdma.h | 375 ++++++++++++++++++++++
10 files changed, 1956 insertions(+)
create mode 100644 drivers/dma/ptdma/Kconfig
create mode 100644 drivers/dma/ptdma/Makefile
create mode 100644 drivers/dma/ptdma/ptdma-debugfs.c
create mode 100644 drivers/dma/ptdma/ptdma-dev.c
create mode 100644 drivers/dma/ptdma/ptdma-dmaengine.c
create mode 100644 drivers/dma/ptdma/ptdma-pci.c
create mode 100644 drivers/dma/ptdma/ptdma.h

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2.7.4