convert MkClkCon to iterator

[pinmux.git] / docs / AddingPeripherals.mdwn

diff --git a/docs/AddingPeripherals.mdwn b/docs/AddingPeripherals.mdwn
index 263e7a25e874b3c70c5a673b65de2af81edae6a0..f6f09aceacf94e89ea9f75c030c497015beb1962 100644 (file)
--- a/docs/AddingPeripherals.mdwn
+++ b/docs/AddingPeripherals.mdwn
@@ -1168,6 +1168,27 @@ using the following commands:
     $ ./bin/gitmoduleupdate.sh
     $ make
 
+As the compilation of the soc can take some time, it is possible to use
+the Makefile.peripherals to compile *only* the slow\_peripherals.bsv
+file (which we did not do with the sdram case because sdram is a fast
+peripheral).  This would be achieved with the following commands:
+
+    $ make spec_to_pinmux
+    $ make pinmux_to_bsv
+    $ cd build/i_class/bsv_src
+    $ make -f Makefile.peripherals gen_verilog
+
+## Summary
+
+This particular example has been something of a "cheat".  The similarity
+between SD/MMC and eMMC is so high - the only differences being the name
+of the interface and the number of data pins - that it was simple and
+straightforward to re-use significant amounts of code, cut/paste style,
+carrying out some re-factoring where needed.
+
+It does however have the advantage of being quite a short tutorial, that
+illustrates key aspects of adding slow bus peripherals.
+
 # Conclusion
 
 This is not a small project, by any means.  However the payoff in saved