Decouple dw-edma-core.c from struct pci_dev as a step toward integration
of dw-edma with pci-epf-test so the latter can initiate dma operations
locally from the endpoint side. A barrier to such integration is the
dependency of dw_edma_probe() and other functions in dw-edma-core.c on
struct pci_dev.
The Synopsys DesignWare dw-edma driver was designed to run on host side
of PCIe link to initiate DMA operations remotely using eDMA channels of
PCIe controller on the endpoint side. This can be inferred from seeing
that dw-edma uses struct pci_dev and accesses hardware registers of dma
channels across the bus using BAR0 and BAR2.
The ops field of struct dw_edma in dw-edma-core.h is currenty undefined:
const struct dw_edma_core_ops *ops;
However, the kernel builds without failure even when dw-edma driver is
enabled. Instead of removing the currently undefined and usued ops field,
define struct dw_edma_core_ops and use the ops field to decouple
dw-edma-core.c from struct pci_dev.
Signed-off-by: Alan Mikhak <alan.mikhak@sifive.com>
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Link: https://lore.kernel.org/r/1586971629-30196-1-git-send-email-alan.mikhak@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The new driver mixes up dma_addr_t and __iomem pointers, which results
in warnings on some 32-bit architectures, like:
drivers/dma/dw-edma/dw-edma-v0-core.c: In function '__dw_regs':
drivers/dma/dw-edma/dw-edma-v0-core.c:28:9: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
return (struct dw_edma_v0_regs __iomem *)dw->rg_region.vaddr;
Make it use __iomem pointers consistently here, and avoid using dma_addr_t
for __iomem tokens altogether.
A small complication here is the debugfs code, which passes an __iomem
token as the private data for debugfs files, requiring the use of
extra __force.
Fixes: 7e4b8a4fbe ("dmaengine: Add Synopsys eDMA IP version 0 support")
Link: https://lore.kernel.org/lkml/20190617131918.2518727-1-arnd@arndb.de/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20190722124457.1093886-2-arnd@arndb.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Synopsys eDMA IP is normally distributed along with Synopsys PCIe
EndPoint IP (depends of the use and licensing agreement).
This IP requires some basic configurations, such as:
- eDMA registers BAR
- eDMA registers offset
- eDMA registers size
- eDMA linked list memory BAR
- eDMA linked list memory offset
- eDMA linked list memory size
- eDMA data memory BAR
- eDMA data memory offset
- eDMA data memory size
- eDMA version
- eDMA mode
- IRQs available for eDMA
As a working example, PCIe glue-logic will attach to a Synopsys PCIe
EndPoint IP prototype kit (Vendor ID = 0x16c3, Device ID = 0xedda),
which has built-in an eDMA IP with this default configuration:
- eDMA registers BAR = 0
- eDMA registers offset = 0x00001000 (4 Kbytes)
- eDMA registers size = 0x00002000 (8 Kbytes)
- eDMA linked list memory BAR = 2
- eDMA linked list memory offset = 0x00000000 (0 Kbytes)
- eDMA linked list memory size = 0x00800000 (8 Mbytes)
- eDMA data memory BAR = 2
- eDMA data memory offset = 0x00800000 (8 Mbytes)
- eDMA data memory size = 0x03800000 (56 Mbytes)
- eDMA version = 0
- eDMA mode = EDMA_MODE_UNROLL
- IRQs = 1
This driver can be compile as built-in or external module in kernel.
To enable this driver just select DW_EDMA_PCIE option in kernel
configuration, however it requires and selects automatically DW_EDMA
option too.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
