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UserGuideMmcDriver PSP 04.02.00.07
TI DM35x/37x/AM3517 has an multimedia card high-speed/secure data/secure digital I/O (MMC/SD/SDIO) host controller, which provides an interface between microprocessor and either MMC, SD memory cards, or SDIO cards. The current version of the user guide talks about the MMC/SD controller. The MMC driver is implemented on top of host controller as a HS-MMC controller driver and supports MMC, SD, SD High Speed and SDHC cards. The salient features of the aforementioned HS-MMC host controller are:
- Full compliance with MMC/SD command/response sets as defined in
1-bit or 4-bit transfer mode specifications for SD and SDIO cards 1-bit, 4-bit, or 8-bit transfer mode specifications for MMC cards
- Built-in 1024-byte buffer for read or write
- 32-bit-wide access bus to maximize bus throughput
- Single interrupt line for multiple interrupt source events
- Two slave DMA channels (1 for TX, 1 for RX)
- Designed for low power and Programmable clock generation
Acronyms & Definitions
|HS-MMC||High Speed MMC|
|SDHC||SD High Capacity|
The MMC/SD/SDIO driver supports following features
- The driver is built in-kernel (part of vmlinux).
- MMC cards including High Speed cards.
- SD cards including SD High Speed and SDHC cards
- Uses block bounce buffer to aggregate scattered blocks
The default kernel configuration enables support for MMC/SD(built-in to kernel).
The selection of MMC/SD/SDIO driver can be modified as follows: start Linux Kernel Configuration tool.
$ make menuconfig ARCH=arm
- Select Device Drivers from the main menu.
... ... Kernel Features ---> Boot options ---> CPU Power Management ---> Floating point emulation ---> Userspace binary formats ---> Power management options ---> [*] Networking support ---> Device Drivers ---> ... ...
- Select MMC/SD/SDIO card support from the menu.
... ... [*] USB support ---> <*> MMC/SD/SDIO card support ---> < > Sony MemoryStick card support (EXPERIMENTAL) ---> ... ...
- Select OMAP HS MMC driver
... [ ] MMC debugging [ ] Assume MMC/SD cards are non-removable (DANGEROUS) *** MMC/SD/SDIO Card Drivers *** <*> MMC block device driver [*] Use bounce buffer for simple hosts ... <*> TI OMAP High Speed Multimedia Card Interface support ...