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      1 // SPDX-License-Identifier: GPL-2.0+
      2 /*
      3  * Copyright (c) 2001 Navin Boppuri / Prashant Patel
      4  *	<nboppuri (at) trinetcommunication.com>,
      5  *	<pmpatel (at) trinetcommunication.com>
      6  * Copyright (c) 2001 Gerd Mennchen <Gerd.Mennchen (at) icn.siemens.de>
      7  * Copyright (c) 2001 Wolfgang Denk, DENX Software Engineering, <wd (at) denx.de>.
      8  */
      9 
     10 /*
     11  * MPC8xx CPM SPI interface.
     12  *
     13  * Parts of this code are probably not portable and/or specific to
     14  * the board which I used for the tests. Please send fixes/complaints
     15  * to wd (at) denx.de
     16  *
     17  */
     18 
     19 #include <common.h>
     20 #include <mpc8xx.h>
     21 #include <asm/cpm_8xx.h>
     22 #include <linux/ctype.h>
     23 #include <malloc.h>
     24 #include <post.h>
     25 #include <serial.h>
     26 
     27 #define SPI_EEPROM_WREN		0x06
     28 #define SPI_EEPROM_RDSR		0x05
     29 #define SPI_EEPROM_READ		0x03
     30 #define SPI_EEPROM_WRITE	0x02
     31 
     32 /* ---------------------------------------------------------------
     33  * Offset for initial SPI buffers in DPRAM:
     34  * We need a 520 byte scratch DPRAM area to use at an early stage.
     35  * It is used between the two initialization calls (spi_init_f()
     36  * and spi_init_r()).
     37  * The value 0xb00 makes it far enough from the start of the data
     38  * area (as well as from the stack pointer).
     39  * --------------------------------------------------------------- */
     40 #ifndef	CONFIG_SYS_SPI_INIT_OFFSET
     41 #define	CONFIG_SYS_SPI_INIT_OFFSET	0xB00
     42 #endif
     43 
     44 #define CPM_SPI_BASE_RX	CPM_SPI_BASE
     45 #define CPM_SPI_BASE_TX	(CPM_SPI_BASE + sizeof(cbd_t))
     46 
     47 /* -------------------
     48  * Function prototypes
     49  * ------------------- */
     50 ssize_t spi_xfer(size_t);
     51 
     52 /* -------------------
     53  * Variables
     54  * ------------------- */
     55 
     56 #define MAX_BUFFER	0x104
     57 
     58 /* ----------------------------------------------------------------------
     59  * Initially we place the RX and TX buffers at a fixed location in DPRAM!
     60  * ---------------------------------------------------------------------- */
     61 static uchar *rxbuf =
     62 	(uchar *)&((cpm8xx_t *)&((immap_t *)CONFIG_SYS_IMMR)->im_cpm)->cp_dpmem
     63 			[CONFIG_SYS_SPI_INIT_OFFSET];
     64 static uchar *txbuf =
     65 	(uchar *)&((cpm8xx_t *)&((immap_t *)CONFIG_SYS_IMMR)->im_cpm)->cp_dpmem
     66 			[CONFIG_SYS_SPI_INIT_OFFSET+MAX_BUFFER];
     67 
     68 /* **************************************************************************
     69  *
     70  *  Function:    spi_init_f
     71  *
     72  *  Description: Init SPI-Controller (ROM part)
     73  *
     74  *  return:      ---
     75  *
     76  * *********************************************************************** */
     77 void spi_init_f(void)
     78 {
     79 	immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
     80 	cpm8xx_t __iomem *cp = &immr->im_cpm;
     81 	spi_t __iomem *spi = (spi_t __iomem *)&cp->cp_dparam[PROFF_SPI];
     82 	cbd_t __iomem *tbdf, *rbdf;
     83 
     84 	/* Disable relocation */
     85 	out_be16(&spi->spi_rpbase, 0);
     86 
     87 /* 1 */
     88 	/* ------------------------------------------------
     89 	 * Initialize Port B SPI pins -> page 34-8 MPC860UM
     90 	 * (we are only in Master Mode !)
     91 	 * ------------------------------------------------ */
     92 
     93 	/* --------------------------------------------
     94 	 * GPIO or per. Function
     95 	 * PBPAR[28] = 1 [0x00000008] -> PERI: (SPIMISO)
     96 	 * PBPAR[29] = 1 [0x00000004] -> PERI: (SPIMOSI)
     97 	 * PBPAR[30] = 1 [0x00000002] -> PERI: (SPICLK)
     98 	 * PBPAR[31] = 0 [0x00000001] -> GPIO: (CS for PCUE/CCM-EEPROM)
     99 	 * -------------------------------------------- */
    100 	clrsetbits_be32(&cp->cp_pbpar, 0x00000001, 0x0000000E);	/* set  bits */
    101 
    102 	/* ----------------------------------------------
    103 	 * In/Out or per. Function 0/1
    104 	 * PBDIR[28] = 1 [0x00000008] -> PERI1: SPIMISO
    105 	 * PBDIR[29] = 1 [0x00000004] -> PERI1: SPIMOSI
    106 	 * PBDIR[30] = 1 [0x00000002] -> PERI1: SPICLK
    107 	 * PBDIR[31] = 1 [0x00000001] -> GPIO OUT: CS for PCUE/CCM-EEPROM
    108 	 * ---------------------------------------------- */
    109 	setbits_be32(&cp->cp_pbdir, 0x0000000F);
    110 
    111 	/* ----------------------------------------------
    112 	 * open drain or active output
    113 	 * PBODR[28] = 1 [0x00000008] -> open drain: SPIMISO
    114 	 * PBODR[29] = 0 [0x00000004] -> active output SPIMOSI
    115 	 * PBODR[30] = 0 [0x00000002] -> active output: SPICLK
    116 	 * PBODR[31] = 0 [0x00000001] -> active output GPIO OUT: CS for PCUE/CCM
    117 	 * ---------------------------------------------- */
    118 
    119 	clrsetbits_be16(&cp->cp_pbodr, 0x00000007, 0x00000008);
    120 
    121 	/* Initialize the parameter ram.
    122 	 * We need to make sure many things are initialized to zero
    123 	 */
    124 	out_be32(&spi->spi_rstate, 0);
    125 	out_be32(&spi->spi_rdp, 0);
    126 	out_be16(&spi->spi_rbptr, 0);
    127 	out_be16(&spi->spi_rbc, 0);
    128 	out_be32(&spi->spi_rxtmp, 0);
    129 	out_be32(&spi->spi_tstate, 0);
    130 	out_be32(&spi->spi_tdp, 0);
    131 	out_be16(&spi->spi_tbptr, 0);
    132 	out_be16(&spi->spi_tbc, 0);
    133 	out_be32(&spi->spi_txtmp, 0);
    134 
    135 /* 3 */
    136 	/* Set up the SPI parameters in the parameter ram */
    137 	out_be16(&spi->spi_rbase, CPM_SPI_BASE_RX);
    138 	out_be16(&spi->spi_tbase, CPM_SPI_BASE_TX);
    139 
    140 	/***********IMPORTANT******************/
    141 
    142 	/*
    143 	 * Setting transmit and receive buffer descriptor pointers
    144 	 * initially to rbase and tbase. Only the microcode patches
    145 	 * documentation talks about initializing this pointer. This
    146 	 * is missing from the sample I2C driver. If you dont
    147 	 * initialize these pointers, the kernel hangs.
    148 	 */
    149 	out_be16(&spi->spi_rbptr, CPM_SPI_BASE_RX);
    150 	out_be16(&spi->spi_tbptr, CPM_SPI_BASE_TX);
    151 
    152 /* 4 */
    153 	/* Init SPI Tx + Rx Parameters */
    154 	while (in_be16(&cp->cp_cpcr) & CPM_CR_FLG)
    155 		;
    156 
    157 	out_be16(&cp->cp_cpcr, mk_cr_cmd(CPM_CR_CH_SPI, CPM_CR_INIT_TRX) |
    158 			       CPM_CR_FLG);
    159 	while (in_be16(&cp->cp_cpcr) & CPM_CR_FLG)
    160 		;
    161 
    162 /* 5 */
    163 	/* Set SDMA configuration register */
    164 	out_be32(&immr->im_siu_conf.sc_sdcr, 0x0001);
    165 
    166 /* 6 */
    167 	/* Set to big endian. */
    168 	out_8(&spi->spi_tfcr, SMC_EB);
    169 	out_8(&spi->spi_rfcr, SMC_EB);
    170 
    171 /* 7 */
    172 	/* Set maximum receive size. */
    173 	out_be16(&spi->spi_mrblr, MAX_BUFFER);
    174 
    175 /* 8 + 9 */
    176 	/* tx and rx buffer descriptors */
    177 	tbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_TX];
    178 	rbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_RX];
    179 
    180 	clrbits_be16(&tbdf->cbd_sc, BD_SC_READY);
    181 	clrbits_be16(&rbdf->cbd_sc, BD_SC_EMPTY);
    182 
    183 	/* Set the bd's rx and tx buffer address pointers */
    184 	out_be32(&rbdf->cbd_bufaddr, (ulong)rxbuf);
    185 	out_be32(&tbdf->cbd_bufaddr, (ulong)txbuf);
    186 
    187 /* 10 + 11 */
    188 	out_8(&cp->cp_spim, 0);			/* Mask  all SPI events */
    189 	out_8(&cp->cp_spie, SPI_EMASK);		/* Clear all SPI events	*/
    190 
    191 	return;
    192 }
    193 
    194 /* **************************************************************************
    195  *
    196  *  Function:    spi_init_r
    197  *
    198  *  Description: Init SPI-Controller (RAM part) -
    199  *		 The malloc engine is ready and we can move our buffers to
    200  *		 normal RAM
    201  *
    202  *  return:      ---
    203  *
    204  * *********************************************************************** */
    205 void spi_init_r(void)
    206 {
    207 	immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
    208 	cpm8xx_t __iomem *cp = &immr->im_cpm;
    209 	spi_t __iomem *spi = (spi_t __iomem *)&cp->cp_dparam[PROFF_SPI];
    210 	cbd_t __iomem *tbdf, *rbdf;
    211 
    212 	/* Disable relocation */
    213 	out_be16(&spi->spi_rpbase, 0);
    214 
    215 	/* tx and rx buffer descriptors */
    216 	tbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_TX];
    217 	rbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_RX];
    218 
    219 	/* Allocate memory for RX and TX buffers */
    220 	rxbuf = (uchar *)malloc(MAX_BUFFER);
    221 	txbuf = (uchar *)malloc(MAX_BUFFER);
    222 
    223 	out_be32(&rbdf->cbd_bufaddr, (ulong)rxbuf);
    224 	out_be32(&tbdf->cbd_bufaddr, (ulong)txbuf);
    225 
    226 	return;
    227 }
    228 
    229 /****************************************************************************
    230  *  Function:    spi_write
    231  **************************************************************************** */
    232 ssize_t spi_write(uchar *addr, int alen, uchar *buffer, int len)
    233 {
    234 	int i;
    235 
    236 	memset(rxbuf, 0, MAX_BUFFER);
    237 	memset(txbuf, 0, MAX_BUFFER);
    238 	*txbuf = SPI_EEPROM_WREN;		/* write enable		*/
    239 	spi_xfer(1);
    240 	memcpy(txbuf, addr, alen);
    241 	*txbuf = SPI_EEPROM_WRITE;		/* WRITE memory array	*/
    242 	memcpy(alen + txbuf, buffer, len);
    243 	spi_xfer(alen + len);
    244 						/* ignore received data	*/
    245 	for (i = 0; i < 1000; i++) {
    246 		*txbuf = SPI_EEPROM_RDSR;	/* read status		*/
    247 		txbuf[1] = 0;
    248 		spi_xfer(2);
    249 		if (!(rxbuf[1] & 1))
    250 			break;
    251 		udelay(1000);
    252 	}
    253 	if (i >= 1000)
    254 		printf("*** spi_write: Time out while writing!\n");
    255 
    256 	return len;
    257 }
    258 
    259 /****************************************************************************
    260  *  Function:    spi_read
    261  **************************************************************************** */
    262 ssize_t spi_read(uchar *addr, int alen, uchar *buffer, int len)
    263 {
    264 	memset(rxbuf, 0, MAX_BUFFER);
    265 	memset(txbuf, 0, MAX_BUFFER);
    266 	memcpy(txbuf, addr, alen);
    267 	*txbuf = SPI_EEPROM_READ;		/* READ memory array	*/
    268 
    269 	/*
    270 	 * There is a bug in 860T (?) that cuts the last byte of input
    271 	 * if we're reading into DPRAM. The solution we choose here is
    272 	 * to always read len+1 bytes (we have one extra byte at the
    273 	 * end of the buffer).
    274 	 */
    275 	spi_xfer(alen + len + 1);
    276 	memcpy(buffer, alen + rxbuf, len);
    277 
    278 	return len;
    279 }
    280 
    281 /****************************************************************************
    282  *  Function:    spi_xfer
    283  **************************************************************************** */
    284 ssize_t spi_xfer(size_t count)
    285 {
    286 	immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
    287 	cpm8xx_t __iomem *cp = &immr->im_cpm;
    288 	spi_t __iomem *spi = (spi_t __iomem *)&cp->cp_dparam[PROFF_SPI];
    289 	cbd_t __iomem *tbdf, *rbdf;
    290 	int tm;
    291 
    292 	/* Disable relocation */
    293 	out_be16(&spi->spi_rpbase, 0);
    294 
    295 	tbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_TX];
    296 	rbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_RX];
    297 
    298 	/* Set CS for device */
    299 	clrbits_be32(&cp->cp_pbdat, 0x0001);
    300 
    301 	/* Setting tx bd status and data length */
    302 	out_be16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_LAST | BD_SC_WRAP);
    303 	out_be16(&tbdf->cbd_datlen, count);
    304 
    305 	/* Setting rx bd status and data length */
    306 	out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_WRAP);
    307 	out_be16(&rbdf->cbd_datlen, 0);	 /* rx length has no significance */
    308 
    309 	clrsetbits_be16(&cp->cp_spmode, ~SPMODE_LOOP, SPMODE_REV | SPMODE_MSTR |
    310 			SPMODE_EN | SPMODE_LEN(8) | SPMODE_PM(0x8));
    311 	out_8(&cp->cp_spim, 0);		/* Mask  all SPI events */
    312 	out_8(&cp->cp_spie, SPI_EMASK);	/* Clear all SPI events	*/
    313 
    314 	/* start spi transfer */
    315 	setbits_8(&cp->cp_spcom, SPI_STR);		/* Start transmit */
    316 
    317 	/* --------------------------------
    318 	 * Wait for SPI transmit to get out
    319 	 * or time out (1 second = 1000 ms)
    320 	 * -------------------------------- */
    321 	for (tm = 0; tm < 1000; ++tm) {
    322 		if (in_8(&cp->cp_spie) & SPI_TXB)	/* Tx Buffer Empty */
    323 			break;
    324 		if ((in_be16(&tbdf->cbd_sc) & BD_SC_READY) == 0)
    325 			break;
    326 		udelay(1000);
    327 	}
    328 	if (tm >= 1000)
    329 		printf("*** spi_xfer: Time out while xferring to/from SPI!\n");
    330 
    331 	/* Clear CS for device */
    332 	setbits_be32(&cp->cp_pbdat, 0x0001);
    333 
    334 	return count;
    335 }
    336