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BCMA is a Broadcom specific bus with devices AKA cores. All recent BCMA based SoCs have gigabit ethernet provided by the GBit MAC core. This patch adds driver for such a cores registering itself as a netdev. It has been tested on a BCM4706 and BCM4718 chipsets. In the kernel tree there is already b44 driver which has some common things with bgmac, however there are many differences that has led to the decision or writing a new driver: 1) GBit MAC cores appear on BCMA bus (not SSB as in case of b44) 2) There is 64bit DMA engine which differs from 32bit one 3) There is no CAM (Content Addressable Memory) in GBit MAC 4) We have 4 TX queues on GBit MAC devices (instead of 1) 5) Many registers have different addresses/values 6) RX header flags are also different The driver in it's state is functional how, however there is of course place for improvements: 1) Supporting more net_device_ops 2) SUpporting more ethtool_ops 3) Unaligned addressing in DMA 4) Writing separated PHY driver Signed-off-by: Rafał Miłecki <zajec5@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| bcma_private.h | ||
| core.c | ||
| driver_chipcommon_nflash.c | ||
| driver_chipcommon_pmu.c | ||
| driver_chipcommon_sflash.c | ||
| driver_chipcommon.c | ||
| driver_gmac_cmn.c | ||
| driver_gpio.c | ||
| driver_mips.c | ||
| driver_pci_host.c | ||
| driver_pci.c | ||
| host_pci.c | ||
| host_soc.c | ||
| Kconfig | ||
| main.c | ||
| Makefile | ||
| README | ||
| scan.c | ||
| scan.h | ||
| sprom.c | ||
| TODO | ||
Broadcom introduced new bus as replacement for older SSB. It is based on AMBA, however from programming point of view there is nothing AMBA specific we use. Standard AMBA drivers are platform specific, have hardcoded addresses and use AMBA standard fields like CID and PID. In case of Broadcom's cards every device consists of: 1) Broadcom specific AMBA device. It is put on AMBA bus, but can not be treated as standard AMBA device. Reading it's CID or PID can cause machine lockup. 2) AMBA standard devices called ports or wrappers. They have CIDs (AMBA_CID) and PIDs (0x103BB369), but we do not use that info for anything. One of that devices is used for managing Broadcom specific core. Addresses of AMBA devices are not hardcoded in driver and have to be read from EPROM. In this situation we decided to introduce separated bus. It can contain up to 16 devices identified by Broadcom specific fields: manufacturer, id, revision and class.