SPI1 pin conflict:
Added by Thomas Catalino over 12 years ago
(posted on behalf of a customer)
MityDSP has dedicated pins 193, 195 and 197 to SPI1 because they connected it to an SPI NOR flash, however using either pins 195 or 197 Data with the 193 clock for SPI1 results in “IO Set violation” warnings in the Pinmux utility. Is the TI Pinmux utility overly restrictive or is the MityDSP documentation wrong?
From your doc: “Note that the SPI1 chip select 0, however, is reserved in order to support booting from the on-board NOR flash. After bootloading, access to the NOR flash is typically not required, and the SPI port may be used with other chip selects if required.” Are we OK to use the SPI1 pins as documented?
Replies (2)
RE: SPI1 pin conflict: - Added by Michael Williamson over 12 years ago
The MityARM-335x module provides SPI1 SCLK, D0 and D1 on pins 193, 195, and 197 of the edge connector.
On the module, these lines are connected to an on-board SPI NOR FLASH via SPI1_CS0 (Ball C12 on the 3359 package, not available on the edge connector).
We are able to use the NOR device in u-Boot as well as in the kernel. We haven't used the pinmux utility very much and I haven't seen this error, I expect that the tool may be overly restrictive.
Also please note: this FLASH can not be used to bootstrap the device, unfortunately. The Boot ROM from TI does not support booting from SPI1, only SPI0. We discovered this after the module design was complete and released. An unfortunate oversight on our end. If you require booting from NOR flash then, at the moment, you'll need to install a second device onto your baseboard and connect it to SPI0_CS0. We're still looking for solutions to this, but it may be left as it is. Most folks require additional storage anyway due to the typical need for filessytems, etc.
We will also be updating the specifications regarding this as well. Sorry for any inconvenience.
-Mike
RE: SPI1 pin conflict: - Added by Ali Asgar Sohanghpurwala over 12 years ago
Michael Williamson wrote:
The MityARM-335x module provides SPI1 SCLK, D0 and D1 on pins 193, 195, and 197 of the edge connector.
On the module, these lines are connected to an on-board SPI NOR FLASH via SPI1_CS0 (Ball C12 on the 3359 package, not available on the edge connector).
We are able to use the NOR device in u-Boot as well as in the kernel. We haven't used the pinmux utility very much and I haven't seen this error, I expect that the tool may be overly restrictive.
Also please note: this FLASH can not be used to bootstrap the device, unfortunately. The Boot ROM from TI does not support booting from SPI1, only SPI0. We discovered this after the module design was complete and released. An unfortunate oversight on our end. If you require booting from NOR flash then, at the moment, you'll need to install a second device onto your baseboard and connect it to SPI0_CS0. We're still looking for solutions to this, but it may be left as it is. Most folks require additional storage anyway due to the typical need for filessytems, etc.
We will also be updating the specifications regarding this as well. Sorry for any inconvenience.
-Mike
No problem, we will most likely boot off MMC. The PinMux utility associates Pin 193 with SPI1_SCLK_MUX0 the 195/197 data lines are from from SPI1_MUX2. Since you guys have the SPI NOR working and I can't find anything in the datasheet/technical user's guide about this SPI MUX, I will chalk this up to an overly restrictive tool.
Thanks,
Ali
