Add EPCS Controller bootrom work-around for Nios-II -When booting from an epcs controller, the epcs bootrom may leave the slave select in an asserted state causing soft reset hang. This patch ensures slave select is negated at reset.
Regards, --Scott
--- u-boot-current/CHANGELOG 2005-08-11 10:41:00.000000000 -0400 +++ u-boot-new/CHANGELOG 2005-08-11 10:45:49.000000000 -0400 @@ -26,6 +26,12 @@ Command line of course produces bigger images, and may be inappropriate for some targets, so by default it's off.
+* Add EPCS Controller bootrom work-around for Nios-II + Patch by Scott McNutt + -When booting from an epcs controller, the epcs bootrom may leave the + slave select in an asserted state causing soft reset hang. This + patch ensures slave select is negated at reset. + * Update PK1C20 board for Nios-II 5.0 Patch by Scott McNutt -Update base addresses for standard configuration diff -Naurb u-boot-current/cpu/nios2/epcs.c u-boot-new/cpu/nios2/epcs.c --- u-boot-current/cpu/nios2/epcs.c 2005-08-09 13:24:21.000000000 -0400 +++ u-boot-new/cpu/nios2/epcs.c 2005-08-10 10:18:31.000000000 -0400 @@ -210,6 +210,21 @@ { 0, 0, 0, 0, 0, 0 } };
+int epcs_reset (void) +{ + /* When booting from an epcs controller, the epcs bootrom + * code may leave the slave select in an asserted state. + * This causes two problems: (1) The initial epcs access + * will fail -- not a big deal, and (2) a software reset + * will cause the bootrom code to hang since it does not + * ensure the select is negated prior to first access -- a + * big deal. Here we just negate chip select and everything + * gets better :-) + */ + epcs_cs (0); /* Negate chip select */ + return (0); +} + epcs_devinfo_t *epcs_dev_find (void) { unsigned char buf[4]; diff -Naurb u-boot-current/include/nios2-epcs.h u-boot-new/include/nios2-epcs.h --- u-boot-current/include/nios2-epcs.h 2005-03-30 18:28:19.000000000 -0500 +++ u-boot-new/include/nios2-epcs.h 2005-08-10 10:15:40.000000000 -0400 @@ -38,6 +38,11 @@ unsigned char prot_mask; /* Protection mask */ }epcs_devinfo_t;
+/* Resets the epcs controller -- to prevent (potential) soft-reset + * problems when booting from the epcs controller + */ +extern int epcs_reset (void); + /* Returns the devinfo struct if EPCS device is found; * NULL otherwise. */ diff -Naurb u-boot-current/lib_nios2/board.c u-boot-new/lib_nios2/board.c --- u-boot-current/lib_nios2/board.c 2004-10-10 17:27:35.000000000 -0400 +++ u-boot-new/lib_nios2/board.c 2005-08-10 10:15:55.000000000 -0400 @@ -31,6 +31,9 @@ #ifdef CONFIG_STATUS_LED #include <status_led.h> #endif +#if defined(CFG_NIOS_EPCSBASE) +#include <nios2-epcs.h> +#endif
/* @@ -92,6 +95,9 @@ #if defined(CONFIG_BOARD_EARLY_INIT_F) board_early_init_f, /* Call board-specific init code early.*/ #endif +#if defined(CFG_NIOS_EPCSBASE) + epcs_reset, +#endif
env_init, serial_init, @@ -166,6 +172,10 @@ WATCHDOG_RESET (); interrupt_init ();
+#if defined(CONFIG_BOARD_LATE_INIT) + board_late_init (); +#endif + /* main_loop */ for (;;) { WATCHDOG_RESET ();