--- /dev/null
+/***************************************************************************
+ * Copyright (C) 2019 by Andreas Bolsch *
+ * andreas.bolsch@mni.thm.de *
+ * *
+ * 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, see <http://www.gnu.org/licenses/>. *
+ ***************************************************************************/
+
+ .text
+ .syntax unified
+ .cpu cortex-m0
+ .thumb
+ .thumb_func
+
+/* Params:
+ * r0 - total count (bytes), crc32 (out)
+ * r1 - flash page size
+ * r2 - address offset into flash
+ * r3 - OCTOSPI io_base
+
+ * Clobbered:
+ * r4 - tmp
+ * r5 - address of OCTOSPI_DR
+ * r6 - address of OCTOSPI_CCR
+ * r7 - tmp
+ */
+
+#include "../../../../src/flash/nor/stmqspi.h"
+
+#define OCTOSPI_CCR_CCR (OCTOSPI_CCR - OCTOSPI_CCR)
+#define OCTOSPI_TCR_CCR (OCTOSPI_TCR - OCTOSPI_CCR)
+#define OCTOSPI_IR_CCR (OCTOSPI_IR - OCTOSPI_CCR)
+
+ .macro octospi_abort
+ movs r5, #(1<<SPI_ABORT) /* abort bit mask */
+ ldr r7, [r3, #OCTOSPI_CR] /* get OCTOSPI CR register */
+ orrs r7, r7, r5 /* set abort bit */
+ str r7, [r3, #OCTOSPI_CR] /* store new CR register */
+ .endm
+
+ .macro wait_busy
+0:
+ ldr r7, [r3, #OCTOSPI_SR] /* load status */
+ lsrs r7, r7, #(SPI_BUSY+1) /* shift BUSY into C */
+ bcs 0b /* loop until BUSY cleared */
+ movs r7, #(1<<SPI_TCF) /* TCF bitmask */
+ str r7, [r3, #OCTOSPI_FCR] /* clear TCF flag */
+ .endm
+
+start:
+ subs r0, r0, #1 /* decrement count for DLR */
+ subs r1, r1, #1 /* page size mask and for DLR */
+ movs r4, #0x00 /* initialize crc */
+ mvns r4, r4 /* to 0xFFFFFFFF */
+start_read:
+ octospi_abort /* start in clean state */
+ movs r5, #OCTOSPI_DR /* load OCTOSPI_DR address offset */
+ adds r5, r5, r3 /* address of OCTOSPI_DR */
+ movs r6, #OCTOSPI_CCR-OCTOSPI_DR /* load OCTOSPI_CCR address offset */
+ adds r6, r6, r5 /* address of OCTOSPI_CCR */
+ wait_busy
+ ldr r7, cr_page_read /* indirect read mode */
+ str r7, [r3, #OCTOSPI_CR] /* set mode */
+ mov r7, r2 /* get current start address */
+ orrs r7, r7, r1 /* end of current page */
+ subs r7, r7, r2 /* count-1 to end of page */
+ cmp r7, r0 /* if this count <= remaining */
+ bls write_dlr /* then read to end of page */
+ mov r7, r0 /* else read all remaining */
+write_dlr:
+ str r7, [r3, #OCTOSPI_DLR] /* size-1 in DLR register */
+ ldr r7, ccr_page_read /* CCR for read */
+ str r7, [r6, #OCTOSPI_CCR_CCR] /* initiate transfer */
+ ldr r7, tcr_page_read /* TCR for read */
+ str r7, [r6, #OCTOSPI_TCR_CCR] /* instruction */
+ ldr r7, ir_page_read /* IR for read */
+ str r7, [r6, #OCTOSPI_IR_CCR] /* instruction */
+ str r2, [r3, #OCTOSPI_AR] /* store SPI start address */
+ ldr r6, =0x04C11DB7 /* CRC32 polynomial */
+read_loop:
+ ldrb r7, [r5] /* read next byte from DR */
+ lsls r7, r7, #24 /* shift into msb */
+ eors r4, r4, r7
+ .rept 8 /* unrolled bit loop */
+ asrs r7, r4, #31 /* copy bit 31 into bits 0 to 31 */
+ ands r7, r7, r6 /* r7 neg. -> CRC32XOR, pos. -> 0x0 */
+ lsls r4, r4, #1 /* shift result */
+ eors r4, r4, r7 /* eor by CRC32XOR or 0x0 */
+ .endr
+ adds r2, r2, #1 /* increment address */
+ subs r0, r0, #1 /* decrement (count-1) */
+ bmi exit /* stop if no data left */
+ tst r2, r1 /* page end ? */
+ bne read_loop /* if not, then next byte */
+page_end:
+ bal start_read /* then next page */
+ .pool
+
+exit:
+ mvns r0, r4 /* invert to get final result */
+ octospi_abort /* to idle state */
+ .align 2 /* align to word, bkpt is 4 words */
+ bkpt #0 /* before code end for exit_point */
+ .align 2 /* align to word */
+
+cr_page_read:
+ .space 4 /* OCTOSPI_CR value for read command */
+ccr_page_read:
+ .space 4 /* OCTOSPI_CCR value for read command */
+tcr_page_read:
+ .space 4 /* OCTOSPI_TCR value for read command */
+ir_page_read:
+ .space 4 /* OCTOSPI_IR value for read command */
Code Review / openocd.git / blobdiff