# SD/SDIO software
Source: [https://docs.qualcomm.com/doc/80-88500-4/topic/98_SD_SDIO_software_examples.html](https://docs.qualcomm.com/doc/80-88500-4/topic/98_SD_SDIO_software_examples.html)
SD card is used for external or internal data storage. The diagnostics for device
logging are stored on the SD card and RAM dumps can also be collected on to an SD card. SDIO
supports all SDIO-capable devices, for example, Wi-Fi, Bluetooth wireless technology, and
connecting coprocessor.
Table : Supported features – SD card
| Feature | Comments |
| --- | --- |
| SD card driver | Driver collects RAM dump and uses as external storage |
| SD SDR104 |
- Support for SDR104 Bus Speed mode
- Frequency up to 208 MHz, data rate up to 104 Mbps
|
| GPIO-based SD card detection | SDHC driver uses external GPIO as an interrupt signal to detect SD card insertion
and removal |
Table : Supported features – SDIO
| Feature | Comments |
| --- | --- |
| SDIO for WLAN | Driver support for SDIO to use with WLAN |
Figure : MMC device driver path

| Configuration | Enabled
(Yes/No) | Comments |
| --- | --- | --- |
| CONFIG\_MMC | Yes | Enables MMC driver |
| CONFIG\_MMC\_CLKGATE | Yes | Enables clock gating |
| CONFIG\_MMC\_PARANOID\_SD\_INIT | Yes | Multiple attempts for SD card to resume/attach/setup, etc. |
| CONFIG\_MMC\_UNSAFE\_RESUME | Yes | During suspend, prevents driver from assuming SD card is removed |
| CONFIG\_MMC\_PERF\_PROFILING | Yes | Enables driver performance profiling |
| CONFIG\_MMC\_DEBUG | No | Enables driver debug messages |
| CONFIG\_MMC\_SDHCI | Yes | Detects SDHCI driver |
| CONFIG\_MMC\_TEST | Yes | mmc\_test.c compiled\* |
| \*mmc\_test is compiled as a module. | \*mmc\_test is compiled as a module. | \*mmc\_test is compiled as a module. |
Table : SDHCI power management
| Condition | Clock gating | VDD state | VDD-IO state |
| --- | --- | --- | --- |
| Runtime suspend | Yes | Off | On |
| System suspend | Yes | Off | On |
Table : Performance test conditions – Expected UFS performance
| TIO TEST | SDR104 |
| --- | --- |
| Sequential read (Mbps) | 51 |
| Sequential write (Mbps) | 15 |
Note: For information on the SDHCI debugging, see SDHCI Architecture and
Debugging (80-NL199-1).
**Parent Topic:** [SD/SDIO](https://docs.qualcomm.com/doc/80-88500-4/topic/96_SD_SDIO.html)
Last Published: Aug 18, 2023
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