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Diffstat (limited to 'arch/ppc/cpu/mpc8260/spi.c')
-rw-r--r--arch/ppc/cpu/mpc8260/spi.c435
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diff --git a/arch/ppc/cpu/mpc8260/spi.c b/arch/ppc/cpu/mpc8260/spi.c
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+/*
+ * Copyright (c) 2001 Navin Boppuri / Prashant Patel
+ * <nboppuri@trinetcommunication.com>,
+ * <pmpatel@trinetcommunication.com>
+ * Copyright (c) 2001 Gerd Mennchen <Gerd.Mennchen@icn.siemens.de>
+ * Copyright (c) 2001-2003 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
+ */
+
+/*
+ * MPC8260 CPM SPI interface.
+ *
+ * Parts of this code are probably not portable and/or specific to
+ * the board which I used for the tests. Please send fixes/complaints
+ * to wd@denx.de
+ *
+ */
+
+#include <common.h>
+#include <asm/cpm_8260.h>
+#include <linux/ctype.h>
+#include <malloc.h>
+#include <post.h>
+#include <net.h>
+
+#if defined(CONFIG_SPI)
+
+/* Warning:
+ * You cannot enable DEBUG for early system initalization, i. e. when
+ * this driver is used to read environment parameters like "baudrate"
+ * from EEPROM which are used to initialize the serial port which is
+ * needed to print the debug messages...
+ */
+#undef DEBUG
+
+#define SPI_EEPROM_WREN 0x06
+#define SPI_EEPROM_RDSR 0x05
+#define SPI_EEPROM_READ 0x03
+#define SPI_EEPROM_WRITE 0x02
+
+/* ---------------------------------------------------------------
+ * Offset for initial SPI buffers in DPRAM:
+ * We need a 520 byte scratch DPRAM area to use at an early stage.
+ * It is used between the two initialization calls (spi_init_f()
+ * and spi_init_r()).
+ * The value 0x2000 makes it far enough from the start of the data
+ * area (as well as from the stack pointer).
+ * --------------------------------------------------------------- */
+#ifndef CONFIG_SYS_SPI_INIT_OFFSET
+#define CONFIG_SYS_SPI_INIT_OFFSET 0x2000
+#endif
+
+#define CPM_SPI_BASE 0x100
+
+#ifdef DEBUG
+
+#define DPRINT(a) printf a;
+/* -----------------------------------------------
+ * Helper functions to peek into tx and rx buffers
+ * ----------------------------------------------- */
+static const char * const hex_digit = "0123456789ABCDEF";
+
+static char quickhex (int i)
+{
+ return hex_digit[i];
+}
+
+static void memdump (void *pv, int num)
+{
+ int i;
+ unsigned char *pc = (unsigned char *) pv;
+
+ for (i = 0; i < num; i++)
+ printf ("%c%c ", quickhex (pc[i] >> 4), quickhex (pc[i] & 0x0f));
+ printf ("\t");
+ for (i = 0; i < num; i++)
+ printf ("%c", isprint (pc[i]) ? pc[i] : '.');
+ printf ("\n");
+}
+#else /* !DEBUG */
+
+#define DPRINT(a)
+
+#endif /* DEBUG */
+
+/* -------------------
+ * Function prototypes
+ * ------------------- */
+void spi_init (void);
+
+ssize_t spi_read (uchar *, int, uchar *, int);
+ssize_t spi_write (uchar *, int, uchar *, int);
+ssize_t spi_xfer (size_t);
+
+/* -------------------
+ * Variables
+ * ------------------- */
+
+#define MAX_BUFFER 0x104
+
+/* ----------------------------------------------------------------------
+ * Initially we place the RX and TX buffers at a fixed location in DPRAM!
+ * ---------------------------------------------------------------------- */
+static uchar *rxbuf =
+ (uchar *)&((immap_t *)CONFIG_SYS_IMMR)->im_dprambase
+ [CONFIG_SYS_SPI_INIT_OFFSET];
+static uchar *txbuf =
+ (uchar *)&((immap_t *)CONFIG_SYS_IMMR)->im_dprambase
+ [CONFIG_SYS_SPI_INIT_OFFSET+MAX_BUFFER];
+
+/* **************************************************************************
+ *
+ * Function: spi_init_f
+ *
+ * Description: Init SPI-Controller (ROM part)
+ *
+ * return: ---
+ *
+ * *********************************************************************** */
+void spi_init_f (void)
+{
+ unsigned int dpaddr;
+
+ volatile spi_t *spi;
+ volatile immap_t *immr;
+ volatile cpm8260_t *cp;
+ volatile cbd_t *tbdf, *rbdf;
+
+ immr = (immap_t *) CONFIG_SYS_IMMR;
+ cp = (cpm8260_t *) &immr->im_cpm;
+
+ *(ushort *)(&immr->im_dprambase[PROFF_SPI_BASE]) = PROFF_SPI;
+ spi = (spi_t *)&immr->im_dprambase[PROFF_SPI];
+
+/* 1 */
+ /* ------------------------------------------------
+ * Initialize Port D SPI pins
+ * (we are only in Master Mode !)
+ * ------------------------------------------------ */
+
+ /* --------------------------------------------
+ * GPIO or per. Function
+ * PPARD[16] = 1 [0x00008000] (SPIMISO)
+ * PPARD[17] = 1 [0x00004000] (SPIMOSI)
+ * PPARD[18] = 1 [0x00002000] (SPICLK)
+ * PPARD[12] = 0 [0x00080000] -> GPIO: (CS for ATC EEPROM)
+ * -------------------------------------------- */
+ immr->im_ioport.iop_ppard |= 0x0000E000; /* set bits */
+ immr->im_ioport.iop_ppard &= ~0x00080000; /* reset bit */
+
+ /* ----------------------------------------------
+ * In/Out or per. Function 0/1
+ * PDIRD[16] = 0 [0x00008000] -> PERI1: SPIMISO
+ * PDIRD[17] = 0 [0x00004000] -> PERI1: SPIMOSI
+ * PDIRD[18] = 0 [0x00002000] -> PERI1: SPICLK
+ * PDIRD[12] = 1 [0x00080000] -> GPIO OUT: CS for ATC EEPROM
+ * ---------------------------------------------- */
+ immr->im_ioport.iop_pdird &= ~0x0000E000;
+ immr->im_ioport.iop_pdird |= 0x00080000;
+
+ /* ----------------------------------------------
+ * special option reg.
+ * PSORD[16] = 1 [0x00008000] -> SPIMISO
+ * PSORD[17] = 1 [0x00004000] -> SPIMOSI
+ * PSORD[18] = 1 [0x00002000] -> SPICLK
+ * ---------------------------------------------- */
+ immr->im_ioport.iop_psord |= 0x0000E000;
+
+ /* Initialize the parameter ram.
+ * We need to make sure many things are initialized to zero
+ */
+ spi->spi_rstate = 0;
+ spi->spi_rdp = 0;
+ spi->spi_rbptr = 0;
+ spi->spi_rbc = 0;
+ spi->spi_rxtmp = 0;
+ spi->spi_tstate = 0;
+ spi->spi_tdp = 0;
+ spi->spi_tbptr = 0;
+ spi->spi_tbc = 0;
+ spi->spi_txtmp = 0;
+
+ /* Allocate space for one transmit and one receive buffer
+ * descriptor in the DP ram
+ */
+#ifdef CONFIG_SYS_ALLOC_DPRAM
+ dpaddr = m8260_cpm_dpalloc (sizeof(cbd_t)*2, 8);
+#else
+ dpaddr = CPM_SPI_BASE;
+#endif
+
+/* 3 */
+ /* Set up the SPI parameters in the parameter ram */
+ spi->spi_rbase = dpaddr;
+ spi->spi_tbase = dpaddr + sizeof (cbd_t);
+
+ /***********IMPORTANT******************/
+
+ /*
+ * Setting transmit and receive buffer descriptor pointers
+ * initially to rbase and tbase. Only the microcode patches
+ * documentation talks about initializing this pointer. This
+ * is missing from the sample I2C driver. If you dont
+ * initialize these pointers, the kernel hangs.
+ */
+ spi->spi_rbptr = spi->spi_rbase;
+ spi->spi_tbptr = spi->spi_tbase;
+
+/* 4 */
+ /* Init SPI Tx + Rx Parameters */
+ while (cp->cp_cpcr & CPM_CR_FLG)
+ ;
+ cp->cp_cpcr = mk_cr_cmd(CPM_CR_SPI_PAGE, CPM_CR_SPI_SBLOCK,
+ 0, CPM_CR_INIT_TRX) | CPM_CR_FLG;
+ while (cp->cp_cpcr & CPM_CR_FLG)
+ ;
+
+/* 6 */
+ /* Set to big endian. */
+ spi->spi_tfcr = CPMFCR_EB;
+ spi->spi_rfcr = CPMFCR_EB;
+
+/* 7 */
+ /* Set maximum receive size. */
+ spi->spi_mrblr = MAX_BUFFER;
+
+/* 8 + 9 */
+ /* tx and rx buffer descriptors */
+ tbdf = (cbd_t *) & immr->im_dprambase[spi->spi_tbase];
+ rbdf = (cbd_t *) & immr->im_dprambase[spi->spi_rbase];
+
+ tbdf->cbd_sc &= ~BD_SC_READY;
+ rbdf->cbd_sc &= ~BD_SC_EMPTY;
+
+ /* Set the bd's rx and tx buffer address pointers */
+ rbdf->cbd_bufaddr = (ulong) rxbuf;
+ tbdf->cbd_bufaddr = (ulong) txbuf;
+
+/* 10 + 11 */
+ immr->im_spi.spi_spie = SPI_EMASK; /* Clear all SPI events */
+ immr->im_spi.spi_spim = 0x00; /* Mask all SPI events */
+
+
+ return;
+}
+
+/* **************************************************************************
+ *
+ * Function: spi_init_r
+ *
+ * Description: Init SPI-Controller (RAM part) -
+ * The malloc engine is ready and we can move our buffers to
+ * normal RAM
+ *
+ * return: ---
+ *
+ * *********************************************************************** */
+void spi_init_r (void)
+{
+ volatile spi_t *spi;
+ volatile immap_t *immr;
+ volatile cpm8260_t *cp;
+ volatile cbd_t *tbdf, *rbdf;
+
+ immr = (immap_t *) CONFIG_SYS_IMMR;
+ cp = (cpm8260_t *) &immr->im_cpm;
+
+ spi = (spi_t *)&immr->im_dprambase[PROFF_SPI];
+
+ /* tx and rx buffer descriptors */
+ tbdf = (cbd_t *) & immr->im_dprambase[spi->spi_tbase];
+ rbdf = (cbd_t *) & immr->im_dprambase[spi->spi_rbase];
+
+ /* Allocate memory for RX and TX buffers */
+ rxbuf = (uchar *) malloc (MAX_BUFFER);
+ txbuf = (uchar *) malloc (MAX_BUFFER);
+
+ rbdf->cbd_bufaddr = (ulong) rxbuf;
+ tbdf->cbd_bufaddr = (ulong) txbuf;
+
+ return;
+}
+
+/****************************************************************************
+ * Function: spi_write
+ **************************************************************************** */
+ssize_t spi_write (uchar *addr, int alen, uchar *buffer, int len)
+{
+ int i;
+
+ memset(rxbuf, 0, MAX_BUFFER);
+ memset(txbuf, 0, MAX_BUFFER);
+ *txbuf = SPI_EEPROM_WREN; /* write enable */
+ spi_xfer(1);
+ memcpy(txbuf, addr, alen);
+ *txbuf = SPI_EEPROM_WRITE; /* WRITE memory array */
+ memcpy(alen + txbuf, buffer, len);
+ spi_xfer(alen + len);
+ /* ignore received data */
+ for (i = 0; i < 1000; i++) {
+ *txbuf = SPI_EEPROM_RDSR; /* read status */
+ txbuf[1] = 0;
+ spi_xfer(2);
+ if (!(rxbuf[1] & 1)) {
+ break;
+ }
+ udelay(1000);
+ }
+ if (i >= 1000) {
+ printf ("*** spi_write: Time out while writing!\n");
+ }
+
+ return len;
+}
+
+/****************************************************************************
+ * Function: spi_read
+ **************************************************************************** */
+ssize_t spi_read (uchar *addr, int alen, uchar *buffer, int len)
+{
+ memset(rxbuf, 0, MAX_BUFFER);
+ memset(txbuf, 0, MAX_BUFFER);
+ memcpy(txbuf, addr, alen);
+ *txbuf = SPI_EEPROM_READ; /* READ memory array */
+
+ /*
+ * There is a bug in 860T (?) that cuts the last byte of input
+ * if we're reading into DPRAM. The solution we choose here is
+ * to always read len+1 bytes (we have one extra byte at the
+ * end of the buffer).
+ */
+ spi_xfer(alen + len + 1);
+ memcpy(buffer, alen + rxbuf, len);
+
+ return len;
+}
+
+/****************************************************************************
+ * Function: spi_xfer
+ **************************************************************************** */
+ssize_t spi_xfer (size_t count)
+{
+ volatile immap_t *immr;
+ volatile cpm8260_t *cp;
+ volatile spi_t *spi;
+ cbd_t *tbdf, *rbdf;
+ int tm;
+
+ DPRINT (("*** spi_xfer entered ***\n"));
+
+ immr = (immap_t *) CONFIG_SYS_IMMR;
+ cp = (cpm8260_t *) &immr->im_cpm;
+
+ spi = (spi_t *)&immr->im_dprambase[PROFF_SPI];
+
+ tbdf = (cbd_t *) & immr->im_dprambase[spi->spi_tbase];
+ rbdf = (cbd_t *) & immr->im_dprambase[spi->spi_rbase];
+
+ /* Board-specific: Set CS for device (ATC EEPROM) */
+ immr->im_ioport.iop_pdatd &= ~0x00080000;
+
+ /* Setting tx bd status and data length */
+ tbdf->cbd_sc = BD_SC_READY | BD_SC_LAST | BD_SC_WRAP;
+ tbdf->cbd_datlen = count;
+
+ DPRINT (("*** spi_xfer: Bytes to be xferred: %d ***\n",
+ tbdf->cbd_datlen));
+
+ /* Setting rx bd status and data length */
+ rbdf->cbd_sc = BD_SC_EMPTY | BD_SC_WRAP;
+ rbdf->cbd_datlen = 0; /* rx length has no significance */
+
+ immr->im_spi.spi_spmode = SPMODE_REV |
+ SPMODE_MSTR |
+ SPMODE_EN |
+ SPMODE_LEN(8) | /* 8 Bits per char */
+ SPMODE_PM(0x8) ; /* medium speed */
+ immr->im_spi.spi_spie = SPI_EMASK; /* Clear all SPI events */
+ immr->im_spi.spi_spim = 0x00; /* Mask all SPI events */
+
+ /* start spi transfer */
+ DPRINT (("*** spi_xfer: Performing transfer ...\n"));
+ immr->im_spi.spi_spcom |= SPI_STR; /* Start transmit */
+
+ /* --------------------------------
+ * Wait for SPI transmit to get out
+ * or time out (1 second = 1000 ms)
+ * -------------------------------- */
+ for (tm=0; tm<1000; ++tm) {
+ if (immr->im_spi.spi_spie & SPI_TXB) { /* Tx Buffer Empty */
+ DPRINT (("*** spi_xfer: Tx buffer empty\n"));
+ break;
+ }
+ if ((tbdf->cbd_sc & BD_SC_READY) == 0) {
+ DPRINT (("*** spi_xfer: Tx BD done\n"));
+ break;
+ }
+ udelay (1000);
+ }
+ if (tm >= 1000) {
+ printf ("*** spi_xfer: Time out while xferring to/from SPI!\n");
+ }
+ DPRINT (("*** spi_xfer: ... transfer ended\n"));
+
+#ifdef DEBUG
+ printf ("\nspi_xfer: txbuf after xfer\n");
+ memdump ((void *) txbuf, 16); /* dump of txbuf before transmit */
+ printf ("spi_xfer: rxbuf after xfer\n");
+ memdump ((void *) rxbuf, 16); /* dump of rxbuf after transmit */
+ printf ("\n");
+#endif
+
+ /* Clear CS for device */
+ immr->im_ioport.iop_pdatd |= 0x00080000;
+
+ return count;
+}
+#endif /* CONFIG_SPI */