1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2001 Navin Boppuri / Prashant Patel
4  *	<nboppuri@trinetcommunication.com>,
5  *	<pmpatel@trinetcommunication.com>
6  * Copyright (c) 2001 Gerd Mennchen <Gerd.Mennchen@icn.siemens.de>
7  * Copyright (c) 2001 Wolfgang Denk, DENX Software Engineering, <wd@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@denx.de
16  *
17  */
18 
19 #include <common.h>
20 #include <dm.h>
21 #include <mpc8xx.h>
22 #include <spi.h>
23 #include <linux/delay.h>
24 
25 #include <asm/cpm_8xx.h>
26 #include <asm/io.h>
27 
28 #define CPM_SPI_BASE_RX	CPM_SPI_BASE
29 #define CPM_SPI_BASE_TX	(CPM_SPI_BASE + sizeof(cbd_t))
30 
31 #define MAX_BUFFER	0x104
32 
mpc8xx_spi_probe(struct udevice * dev)33 static int mpc8xx_spi_probe(struct udevice *dev)
34 {
35 	immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
36 	cpm8xx_t __iomem *cp = &immr->im_cpm;
37 	spi_t __iomem *spi = (spi_t __iomem *)&cp->cp_dparam[PROFF_SPI];
38 	cbd_t __iomem *tbdf, *rbdf;
39 
40 	/* Disable relocation */
41 	out_be16(&spi->spi_rpbase, 0);
42 
43 /* 1 */
44 	/* ------------------------------------------------
45 	 * Initialize Port B SPI pins -> page 34-8 MPC860UM
46 	 * (we are only in Master Mode !)
47 	 * ------------------------------------------------ */
48 
49 	/* --------------------------------------------
50 	 * GPIO or per. Function
51 	 * PBPAR[28] = 1 [0x00000008] -> PERI: (SPIMISO)
52 	 * PBPAR[29] = 1 [0x00000004] -> PERI: (SPIMOSI)
53 	 * PBPAR[30] = 1 [0x00000002] -> PERI: (SPICLK)
54 	 * PBPAR[31] = 0 [0x00000001] -> GPIO: (CS for PCUE/CCM-EEPROM)
55 	 * -------------------------------------------- */
56 	clrsetbits_be32(&cp->cp_pbpar, 0x00000001, 0x0000000E);	/* set  bits */
57 
58 	/* ----------------------------------------------
59 	 * In/Out or per. Function 0/1
60 	 * PBDIR[28] = 1 [0x00000008] -> PERI1: SPIMISO
61 	 * PBDIR[29] = 1 [0x00000004] -> PERI1: SPIMOSI
62 	 * PBDIR[30] = 1 [0x00000002] -> PERI1: SPICLK
63 	 * PBDIR[31] = 1 [0x00000001] -> GPIO OUT: CS for PCUE/CCM-EEPROM
64 	 * ---------------------------------------------- */
65 	setbits_be32(&cp->cp_pbdir, 0x0000000F);
66 
67 	/* ----------------------------------------------
68 	 * open drain or active output
69 	 * PBODR[28] = 1 [0x00000008] -> open drain: SPIMISO
70 	 * PBODR[29] = 0 [0x00000004] -> active output SPIMOSI
71 	 * PBODR[30] = 0 [0x00000002] -> active output: SPICLK
72 	 * PBODR[31] = 0 [0x00000001] -> active output GPIO OUT: CS for PCUE/CCM
73 	 * ---------------------------------------------- */
74 
75 	clrsetbits_be16(&cp->cp_pbodr, 0x00000007, 0x00000008);
76 
77 	/* Initialize the parameter ram.
78 	 * We need to make sure many things are initialized to zero
79 	 */
80 	out_be32(&spi->spi_rstate, 0);
81 	out_be32(&spi->spi_rdp, 0);
82 	out_be16(&spi->spi_rbptr, 0);
83 	out_be16(&spi->spi_rbc, 0);
84 	out_be32(&spi->spi_rxtmp, 0);
85 	out_be32(&spi->spi_tstate, 0);
86 	out_be32(&spi->spi_tdp, 0);
87 	out_be16(&spi->spi_tbptr, 0);
88 	out_be16(&spi->spi_tbc, 0);
89 	out_be32(&spi->spi_txtmp, 0);
90 
91 /* 3 */
92 	/* Set up the SPI parameters in the parameter ram */
93 	out_be16(&spi->spi_rbase, CPM_SPI_BASE_RX);
94 	out_be16(&spi->spi_tbase, CPM_SPI_BASE_TX);
95 
96 	/***********IMPORTANT******************/
97 
98 	/*
99 	 * Setting transmit and receive buffer descriptor pointers
100 	 * initially to rbase and tbase. Only the microcode patches
101 	 * documentation talks about initializing this pointer. This
102 	 * is missing from the sample I2C driver. If you dont
103 	 * initialize these pointers, the kernel hangs.
104 	 */
105 	out_be16(&spi->spi_rbptr, CPM_SPI_BASE_RX);
106 	out_be16(&spi->spi_tbptr, CPM_SPI_BASE_TX);
107 
108 /* 4 */
109 	/* Init SPI Tx + Rx Parameters */
110 	while (in_be16(&cp->cp_cpcr) & CPM_CR_FLG)
111 		;
112 
113 	out_be16(&cp->cp_cpcr, mk_cr_cmd(CPM_CR_CH_SPI, CPM_CR_INIT_TRX) |
114 			       CPM_CR_FLG);
115 	while (in_be16(&cp->cp_cpcr) & CPM_CR_FLG)
116 		;
117 
118 /* 5 */
119 	/* Set SDMA configuration register */
120 	out_be32(&immr->im_siu_conf.sc_sdcr, 0x0001);
121 
122 /* 6 */
123 	/* Set to big endian. */
124 	out_8(&spi->spi_tfcr, SMC_EB);
125 	out_8(&spi->spi_rfcr, SMC_EB);
126 
127 /* 7 */
128 	/* Set maximum receive size. */
129 	out_be16(&spi->spi_mrblr, MAX_BUFFER);
130 
131 /* 8 + 9 */
132 	/* tx and rx buffer descriptors */
133 	tbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_TX];
134 	rbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_RX];
135 
136 	clrbits_be16(&tbdf->cbd_sc, BD_SC_READY);
137 	clrbits_be16(&rbdf->cbd_sc, BD_SC_EMPTY);
138 
139 /* 10 + 11 */
140 	out_8(&cp->cp_spim, 0);			/* Mask  all SPI events */
141 	out_8(&cp->cp_spie, SPI_EMASK);		/* Clear all SPI events	*/
142 
143 	return 0;
144 }
145 
mpc8xx_spi_xfer(struct udevice * dev,unsigned int bitlen,const void * dout,void * din,unsigned long flags)146 static int mpc8xx_spi_xfer(struct udevice *dev, unsigned int bitlen,
147 			    const void *dout, void *din, unsigned long flags)
148 {
149 	immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
150 	cpm8xx_t __iomem *cp = &immr->im_cpm;
151 	cbd_t __iomem *tbdf, *rbdf;
152 	int tm;
153 	size_t count = (bitlen + 7) / 8;
154 
155 	if (count > MAX_BUFFER)
156 		return -EINVAL;
157 
158 	tbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_TX];
159 	rbdf = (cbd_t __iomem *)&cp->cp_dpmem[CPM_SPI_BASE_RX];
160 
161 	/* Set CS for device */
162 	clrbits_be32(&cp->cp_pbdat, 0x0001);
163 
164 	/* Setting tx bd status and data length */
165 	out_be32(&tbdf->cbd_bufaddr, (ulong)dout);
166 	out_be16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_LAST | BD_SC_WRAP);
167 	out_be16(&tbdf->cbd_datlen, count);
168 
169 	/* Setting rx bd status and data length */
170 	out_be32(&rbdf->cbd_bufaddr, (ulong)din);
171 	out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_WRAP);
172 	out_be16(&rbdf->cbd_datlen, 0);	 /* rx length has no significance */
173 
174 	clrsetbits_be16(&cp->cp_spmode, ~SPMODE_LOOP, SPMODE_REV | SPMODE_MSTR |
175 			SPMODE_EN | SPMODE_LEN(8) | SPMODE_PM(0x8));
176 	out_8(&cp->cp_spim, 0);		/* Mask  all SPI events */
177 	out_8(&cp->cp_spie, SPI_EMASK);	/* Clear all SPI events	*/
178 
179 	/* start spi transfer */
180 	setbits_8(&cp->cp_spcom, SPI_STR);		/* Start transmit */
181 
182 	/* --------------------------------
183 	 * Wait for SPI transmit to get out
184 	 * or time out (1 second = 1000 ms)
185 	 * -------------------------------- */
186 	for (tm = 0; tm < 1000; ++tm) {
187 		if (in_8(&cp->cp_spie) & SPI_TXB)	/* Tx Buffer Empty */
188 			break;
189 		if ((in_be16(&tbdf->cbd_sc) & BD_SC_READY) == 0)
190 			break;
191 		udelay(1000);
192 	}
193 	if (tm >= 1000)
194 		printf("*** spi_xfer: Time out while xferring to/from SPI!\n");
195 
196 	/* Clear CS for device */
197 	setbits_be32(&cp->cp_pbdat, 0x0001);
198 
199 	return count;
200 }
201 
202 static const struct dm_spi_ops mpc8xx_spi_ops = {
203 	.xfer		= mpc8xx_spi_xfer,
204 };
205 
206 static const struct udevice_id mpc8xx_spi_ids[] = {
207 	{ .compatible = "fsl,mpc8xx-spi" },
208 	{ }
209 };
210 
211 U_BOOT_DRIVER(mpc8xx_spi) = {
212 	.name	= "mpc8xx_spi",
213 	.id	= UCLASS_SPI,
214 	.of_match = mpc8xx_spi_ids,
215 	.ops	= &mpc8xx_spi_ops,
216 	.probe	= mpc8xx_spi_probe,
217 };
218