/* * Copyright (c) 2001 Navin Boppuri / Prashant Patel * , * * Copyright (c) 2001 Gerd Mennchen * Copyright (c) 2001-2003 Wolfgang Denk, DENX Software Engineering, . * * 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 #include #include #include #include #include #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 CFG_SPI_INIT_OFFSET #define CFG_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 *)CFG_IMMR)->im_dprambase [CFG_SPI_INIT_OFFSET]; static uchar *txbuf = (uchar *)&((immap_t *)CFG_IMMR)->im_dprambase [CFG_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 *) CFG_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 CFG_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 *) CFG_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 *) CFG_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 */