Added SPIFI flash driver, algorithms, and docs

[fw/openocd] / contrib / loaders / flash / lpcspifi_init.S

diff --git a/contrib/loaders/flash/lpcspifi_init.S b/contrib/loaders/flash/lpcspifi_init.S
new file mode 100644 (file)
index 0000000..1b373a1
--- /dev/null
+++ b/contrib/loaders/flash/lpcspifi_init.S
@@ -0,0 +1,102 @@
+/***************************************************************************
+ *   Copyright (C) 2012 by George Harris                                          *
+ *   george@luminairecoffee.com                                            *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ ***************************************************************************/
+
+/***************************************************************************
+*      This is an algorithm for the LPC43xx family (and probably the LPC18xx  *
+*      family as well, though they have not been tested) that will initialize *
+*      memory-mapped SPI flash accesses. Unfortunately NXP has published      *
+*      neither the ROM source code that performs this initialization nor the  *
+*      register descriptions necessary to do so, so this code is necessary to *
+*      call into the ROM SPIFI API.                                           *
+***************************************************************************/
+
+       .text
+       .syntax unified
+       .arch armv7-m
+       .thumb
+       .thumb_func
+
+       .align 2
+
+/*
+ * Params :
+ * r0 = spifi clock speed
+ */
+
+#define IOCONFIG_BASE_HIGH          0x4008
+#define IOCONFIG_BASE_LOW           0x6000
+#define IOCONFIG_SCK_OFFSET         0x18c
+#define IOCONFIG_HOLD_OFFSET        0x190
+#define IOCONFIG_WP_OFFSET          0x194
+#define IOCONFIG_MISO_OFFSET        0x198
+#define IOCONFIG_MOSI_OFFSET        0x19c
+#define IOCONFIG_CS_OFFSET          0x1a0
+
+#define SPIFI_ROM_TABLE_BASE_HIGH   0x1040
+#define SPIFI_ROM_TABLE_BASE_LOW    0x0118
+
+code:
+       mov.w   r8, r0
+       sub             sp, #0x84
+       add             r7, sp, #0x0
+       /* Initialize SPIFI pins */
+       mov.w   r3, #IOCONFIG_BASE_LOW
+       movt    r3, #IOCONFIG_BASE_HIGH
+       mov.w   r2, #0xf3
+       str.w   r2, [r3, #IOCONFIG_SCK_OFFSET]
+       mov.w   r3, #IOCONFIG_BASE_LOW
+       movt    r3, #IOCONFIG_BASE_HIGH
+       mov.w   r2, #IOCONFIG_BASE_LOW
+       movt    r2, #IOCONFIG_BASE_HIGH
+       mov.w   r1, #IOCONFIG_BASE_LOW
+       movt    r1, #IOCONFIG_BASE_HIGH
+       mov.w   r0, #IOCONFIG_BASE_LOW
+       movt    r0, #IOCONFIG_BASE_HIGH
+       mov.w   r4, #0xd3
+       str.w   r4, [r0, #IOCONFIG_MOSI_OFFSET]
+       mov     r0, r4
+       str.w   r0, [r1, #IOCONFIG_MISO_OFFSET]
+       mov     r1, r0
+       str.w   r1, [r2, #IOCONFIG_WP_OFFSET]
+       str.w   r1, [r3, #IOCONFIG_HOLD_OFFSET]
+       mov.w   r3, #IOCONFIG_BASE_LOW
+       movt    r3, #IOCONFIG_BASE_HIGH
+       mov.w   r2, #0x13
+       str.w   r2, [r3, #IOCONFIG_CS_OFFSET]
+
+       /* Perform SPIFI init. See spifi_rom_api.h (in NXP lpc43xx driver package) for details */
+       /* on initialization arguments. */
+       movw    r3, #SPIFI_ROM_TABLE_BASE_LOW      /* The ROM API table is located @ 0x10400118, and                    */
+       movt    r3, #SPIFI_ROM_TABLE_BASE_HIGH     /* the first pointer in the struct is to the init function. */
+       ldr     r3, [r3, #0x0]
+       ldr     r4, [r3, #0x0]                           /* Grab the init function pointer from the table */
+       /* Set up function arguments */
+       movw    r0, #0x3b4
+       movt    r0, #0x1000                                   /* Pointer to a SPIFI data struct that we don't care about */
+       mov.w   r1, #0x3                        /* "csHigh". Not 100% sure what this does. */
+       mov.w   r2, #0xc0                                     /* The configuration word: S_RCVCLOCK | S_FULLCLK */
+       mov.w   r3, r8                                        /* SPIFI clock speed (12MHz) */
+       blx     r4                                                          /* Call the init function */
+       b               done
+
+done:
+       bkpt    #0
+
+       .end