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authorwdenk <wdenk>2002-10-01 01:07:28 +0000
committerwdenk <wdenk>2002-10-01 01:07:28 +0000
commite3093091a9d0e7a0709ee79390414b5a5ca69f88 (patch)
treecbe85919e2bbf5937893fdcdfc88343380e694c5 /common
parenta2cecab6df0cfc6206ed3de29abe5d17cd4017a0 (diff)
downloadu-boot-linaro-stable-e3093091a9d0e7a0709ee79390414b5a5ca69f88.tar.gz
Initial revision
Diffstat (limited to 'common')
-rw-r--r--common/cmd_spi.c116
-rw-r--r--common/soft_spi.c138
2 files changed, 254 insertions, 0 deletions
diff --git a/common/cmd_spi.c b/common/cmd_spi.c
new file mode 100644
index 000000000..ccf9cc287
--- /dev/null
+++ b/common/cmd_spi.c
@@ -0,0 +1,116 @@
+/*
+ * (C) Copyright 2002
+ * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+
+/*
+ * SPI Read/Write Utilities
+ */
+
+#include <common.h>
+#include <command.h>
+#include <spi.h>
+#include <cmd_spi.h>
+
+#if (CONFIG_COMMANDS & CFG_CMD_SPI)
+
+#define MAX_SPI_BYTES 32 /* max number of bytes we can handle */
+
+/*
+ * External table of chip select functions (see the appropriate board
+ * support for the actual definition of the table).
+ */
+extern spi_chipsel_type spi_chipsel[];
+
+
+/*
+ * Values from last command.
+ */
+static int device;
+static int bitlen;
+static uchar dout[MAX_SPI_BYTES];
+static uchar din[MAX_SPI_BYTES];
+
+/*
+ * SPI read/write
+ *
+ * Syntax:
+ * spi {dev} {num_bits} {dout}
+ * {dev} is the device number for controlling chip select (see TBD)
+ * {num_bits} is the number of bits to send & receive (base 10)
+ * {dout} is a hexadecimal string of data to send
+ * The command prints out the hexadecimal string received via SPI.
+ */
+
+int do_spi (cmd_tbl_t *cmdtp, bd_t *bd, int flag, int argc, char *argv[])
+{
+ char *cp = 0;
+ uchar tmp;
+ int j;
+ int rcode = 0;
+
+ /*
+ * We use the last specified parameters, unless new ones are
+ * entered.
+ */
+
+ if ((flag & CMD_FLAG_REPEAT) == 0)
+ {
+ if (argc >= 2)
+ device = simple_strtoul(argv[1], NULL, 10);
+ if (argc >= 3)
+ bitlen = simple_strtoul(argv[2], NULL, 10);
+ if (argc >= 4)
+ cp = argv[3];
+ for(j = 0; *cp; j++, cp++) {
+ tmp = *cp - '0';
+ if(tmp > 9)
+ tmp -= ('A' - '0') - 10;
+ if(tmp > 15)
+ tmp -= ('a' - 'A');
+ if(tmp > 15) {
+ printf("Conversion error on %c, bailing out.\n", *cp);
+ break;
+ }
+ if((j % 2) == 0)
+ dout[j / 2] = (tmp << 4);
+ else
+ dout[j / 2] |= tmp;
+ }
+ }
+
+printf("spi_chipsel[%d] = %08X\n", device, (uint)spi_chipsel[device]);
+ if(spi_xfer(spi_chipsel[device], bitlen, dout, din) != 0) {
+ printf("Error with the SPI transaction.\n");
+ rcode = 1;
+ } else {
+ cp = din;
+ for(j = 0; j < ((bitlen + 7) / 8); j++) {
+ printf("%02X", *cp++);
+ }
+ printf("\n");
+ }
+
+ return rcode;
+}
+
+#endif /* CFG_CMD_SPI */
+
diff --git a/common/soft_spi.c b/common/soft_spi.c
new file mode 100644
index 000000000..a5b62f28e
--- /dev/null
+++ b/common/soft_spi.c
@@ -0,0 +1,138 @@
+/*
+ * (C) Copyright 2002
+ * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
+ *
+ * Influenced by code from:
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <spi.h>
+
+#if defined(CONFIG_SOFT_SPI)
+
+#define DEBUG_SPI
+
+
+/*-----------------------------------------------------------------------
+ * Definitions
+ */
+
+#ifdef DEBUG_SPI
+#define PRINTD(fmt,args...) printf (fmt ,##args)
+#else
+#define PRINTD(fmt,args...)
+#endif
+
+
+
+/*=====================================================================*/
+/* Public Functions */
+/*=====================================================================*/
+
+/*-----------------------------------------------------------------------
+ * Initialization
+ */
+void spi_init (void)
+{
+#ifdef SPI_INIT
+ volatile immap_t *immr = (immap_t *)CFG_IMMR;
+
+ SPI_INIT;
+#endif
+}
+
+
+/*-----------------------------------------------------------------------
+ * SPI transfer
+ *
+ * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
+ * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
+ *
+ * The source of the outgoing bits is the "dout" parameter and the
+ * destination of the input bits is the "din" parameter. Note that "dout"
+ * and "din" can point to the same memory location, in which case the
+ * input data overwrites the output data (since both are buffered by
+ * temporary variables, this is OK).
+ *
+ * If the chipsel() function is not NULL, it is called with a parameter
+ * of '1' (chip select active) at the start of the transfer and again with
+ * a parameter of '0' at the end of the transfer.
+ *
+ * If the chipsel() function _is_ NULL, it the responsibility of the
+ * caller to make the appropriate chip select active before calling
+ * spi_xfer() and making it inactive after spi_xfer() returns.
+ */
+int spi_xfer(spi_chipsel_type chipsel, int bitlen, uchar *dout, uchar *din)
+{
+ volatile immap_t *immr = (immap_t *)CFG_IMMR;
+ uchar tmpdin = 0;
+ uchar tmpdout = 0;
+ int j;
+
+ PRINTD("spi_xfer: chipsel %08X dout %08X din %08X bitlen %d\n",
+ (int)chipsel, *(uint *)dout, *(uint *)din, bitlen);
+
+ if(chipsel != NULL) {
+ (*chipsel)(1); /* select the target chip */
+ }
+
+ for(j = 0; j < bitlen; j++) {
+ /*
+ * Check if it is time to work on a new byte.
+ */
+ if((j % 8) == 0) {
+ tmpdout = *dout++;
+ if(j != 0) {
+ *din++ = tmpdin;
+ }
+ tmpdin = 0;
+ }
+ SPI_SCL(0);
+ SPI_SDA(tmpdout & 0x80);
+ SPI_DELAY;
+ SPI_SCL(1);
+ SPI_DELAY;
+ tmpdin <<= 1;
+ tmpdin |= SPI_READ;
+ tmpdout <<= 1;
+ }
+ /*
+ * If the number of bits isn't a multiple of 8, shift the last
+ * bits over to left-justify them. Then store the last byte
+ * read in.
+ */
+ if((bitlen % 8) != 0)
+ tmpdin <<= 8 - (bitlen % 8);
+ *din++ = tmpdin;
+
+ SPI_SCL(0); /* SPI wants the clock left low for idle */
+
+ if(chipsel != NULL) {
+ (*chipsel)(0); /* deselect the target chip */
+
+ }
+
+ return(0);
+}
+
+#endif /* CONFIG_SOFT_SPI */
+