microwatt

Author	SHA1	Message	Date
Anton Blanchard	03fd06deaf	Rework SOC reset The old reset code was overly complicated and never worked properly. Replace it with a simpler sequence that uses a couple of shift registers to assert resets: - Wait a number of external clock cycles before removing reset from the PLL. - After the PLL locks and the external reset button isn't pressed, wait a number of PLL clock cycles before removing reset from the SOC. Signed-off-by: Anton Blanchard <anton@linux.ibm.com>	6 years ago
Anton Blanchard	a53ad60014	Rename a few reset signals clk -> ext_clk reset_n -> ext_rst reset -> rst Signed-off-by: Anton Blanchard <anton@linux.ibm.com>	6 years ago
Anton Blanchard	1fa0b332ca	micropython only requires 512kB of BRAM Mikey points out that our stack grows down from 512kB and our heap is below that too, so we can reduce our BRAM requirements, which allowing some smaller FPGA boards to work. Not sure why I thought we were using memory between 512kB and 1MB. Signed-off-by: Anton Blanchard <anton@linux.ibm.com>	6 years ago
Olof Kindgren	e8ad9bed10	Expose ram init file and memory size through toplevel	6 years ago
Anton Blanchard	5a29cb4699	Initial import of microwatt Signed-off-by: Anton Blanchard <anton@linux.ibm.com>	6 years ago