xref: /openbmc/u-boot/arch/arm/mach-at91/mpddrc.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2013 Atmel Corporation
4  *		      Bo Shen <voice.shen@atmel.com>
5  *
6  * Copyright (C) 2015 Atmel Corporation
7  *		      Wenyou Yang <wenyou.yang@atmel.com>
8  */
9 
10 #include <common.h>
11 #include <asm/io.h>
12 #include <asm/arch/atmel_mpddrc.h>
13 
14 #define SAMA5D3_MPDDRC_VERSION		0x140
15 
16 static inline void atmel_mpddr_op(const struct atmel_mpddr *mpddr,
17 	      int mode,
18 	      u32 ram_address)
19 {
20 	writel(mode, &mpddr->mr);
21 	writel(0, ram_address);
22 }
23 
24 static int ddr2_decodtype_is_seq(const unsigned int base, u32 cr)
25 {
26 	struct atmel_mpddr *mpddr = (struct atmel_mpddr *)base;
27 	u16 version = readl(&mpddr->version) & 0xffff;
28 
29 	if ((version >= SAMA5D3_MPDDRC_VERSION) &&
30 	    (cr & ATMEL_MPDDRC_CR_DECOD_INTERLEAVED))
31 		return 0;
32 
33 	return 1;
34 }
35 
36 
37 int ddr2_init(const unsigned int base,
38 	      const unsigned int ram_address,
39 	      const struct atmel_mpddrc_config *mpddr_value)
40 {
41 	const struct atmel_mpddr *mpddr = (struct atmel_mpddr *)base;
42 
43 	u32 ba_off, cr;
44 
45 	/* Compute bank offset according to NC in configuration register */
46 	ba_off = (mpddr_value->cr & ATMEL_MPDDRC_CR_NC_MASK) + 9;
47 	if (ddr2_decodtype_is_seq(base, mpddr_value->cr))
48 		ba_off += ((mpddr_value->cr & ATMEL_MPDDRC_CR_NR_MASK) >> 2) + 11;
49 
50 	ba_off += (mpddr_value->md & ATMEL_MPDDRC_MD_DBW_MASK) ? 1 : 2;
51 
52 	/* Program the memory device type into the memory device register */
53 	writel(mpddr_value->md, &mpddr->md);
54 
55 	/* Program the configuration register */
56 	writel(mpddr_value->cr, &mpddr->cr);
57 
58 	/* Program the timing register */
59 	writel(mpddr_value->tpr0, &mpddr->tpr0);
60 	writel(mpddr_value->tpr1, &mpddr->tpr1);
61 	writel(mpddr_value->tpr2, &mpddr->tpr2);
62 
63 	/* Issue a NOP command */
64 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NOP_CMD, ram_address);
65 
66 	/* A 200 us is provided to precede any signal toggle */
67 	udelay(200);
68 
69 	/* Issue a NOP command */
70 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NOP_CMD, ram_address);
71 
72 	/* Issue an all banks precharge command */
73 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_PRCGALL_CMD, ram_address);
74 
75 	/* Issue an extended mode register set(EMRS2) to choose operation */
76 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
77 		       ram_address + (0x2 << ba_off));
78 
79 	/* Issue an extended mode register set(EMRS3) to set EMSR to 0 */
80 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
81 		       ram_address + (0x3 << ba_off));
82 
83 	/*
84 	 * Issue an extended mode register set(EMRS1) to enable DLL and
85 	 * program D.I.C (output driver impedance control)
86 	 */
87 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
88 		       ram_address + (0x1 << ba_off));
89 
90 	/* Enable DLL reset */
91 	cr = readl(&mpddr->cr);
92 	writel(cr | ATMEL_MPDDRC_CR_DLL_RESET_ENABLED, &mpddr->cr);
93 
94 	/* A mode register set(MRS) cycle is issued to reset DLL */
95 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_LMR_CMD, ram_address);
96 
97 	/* Issue an all banks precharge command */
98 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_PRCGALL_CMD, ram_address);
99 
100 	/* Two auto-refresh (CBR) cycles are provided */
101 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_RFSH_CMD, ram_address);
102 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_RFSH_CMD, ram_address);
103 
104 	/* Disable DLL reset */
105 	cr = readl(&mpddr->cr);
106 	writel(cr & (~ATMEL_MPDDRC_CR_DLL_RESET_ENABLED), &mpddr->cr);
107 
108 	/* A mode register set (MRS) cycle is issued to disable DLL reset */
109 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_LMR_CMD, ram_address);
110 
111 	/* Set OCD calibration in default state */
112 	cr = readl(&mpddr->cr);
113 	writel(cr | ATMEL_MPDDRC_CR_OCD_DEFAULT, &mpddr->cr);
114 
115 	/*
116 	 * An extended mode register set (EMRS1) cycle is issued
117 	 * to OCD default value
118 	 */
119 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
120 		       ram_address + (0x1 << ba_off));
121 
122 	 /* OCD calibration mode exit */
123 	cr = readl(&mpddr->cr);
124 	writel(cr & (~ATMEL_MPDDRC_CR_OCD_DEFAULT), &mpddr->cr);
125 
126 	/*
127 	 * An extended mode register set (EMRS1) cycle is issued
128 	 * to enable OCD exit
129 	 */
130 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
131 		       ram_address + (0x1 << ba_off));
132 
133 	/* A nornal mode command is provided */
134 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NORMAL_CMD, ram_address);
135 
136 	/* Perform a write access to any DDR2-SDRAM address */
137 	writel(0, ram_address);
138 
139 	/* Write the refresh rate */
140 	writel(mpddr_value->rtr, &mpddr->rtr);
141 
142 	return 0;
143 }
144 
145 int ddr3_init(const unsigned int base,
146 	      const unsigned int ram_address,
147 	      const struct atmel_mpddrc_config *mpddr_value)
148 {
149 	struct atmel_mpddr *mpddr = (struct atmel_mpddr *)base;
150 	u32 ba_off;
151 
152 	/* Compute bank offset according to NC in configuration register */
153 	ba_off = (mpddr_value->cr & ATMEL_MPDDRC_CR_NC_MASK) + 9;
154 	if (ddr2_decodtype_is_seq(base, mpddr_value->cr))
155 		ba_off += ((mpddr_value->cr &
156 			   ATMEL_MPDDRC_CR_NR_MASK) >> 2) + 11;
157 
158 	ba_off += (mpddr_value->md & ATMEL_MPDDRC_MD_DBW_MASK) ? 1 : 2;
159 
160 	/* Program the memory device type */
161 	writel(mpddr_value->md, &mpddr->md);
162 
163 	/*
164 	 * Program features of the DDR3-SDRAM device and timing parameters
165 	 */
166 	writel(mpddr_value->cr, &mpddr->cr);
167 
168 	writel(mpddr_value->tpr0, &mpddr->tpr0);
169 	writel(mpddr_value->tpr1, &mpddr->tpr1);
170 	writel(mpddr_value->tpr2, &mpddr->tpr2);
171 
172 	/* A NOP command is issued to the DDR3-SRAM */
173 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NOP_CMD, ram_address);
174 
175 	/* A pause of at least 500us must be observed before a single toggle. */
176 	udelay(500);
177 
178 	/* A NOP command is issued to the DDR3-SDRAM */
179 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NOP_CMD, ram_address);
180 
181 	/*
182 	 * An Extended Mode Register Set (EMRS2) cycle is issued to choose
183 	 * between commercial or high temperature operations.
184 	 */
185 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
186 		       ram_address + (0x2 << ba_off));
187 	/*
188 	 * Step 7: An Extended Mode Register Set (EMRS3) cycle is issued to set
189 	 * the Extended Mode Register to 0.
190 	 */
191 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
192 		       ram_address + (0x3 << ba_off));
193 	/*
194 	 * An Extended Mode Register Set (EMRS1) cycle is issued to disable and
195 	 * to program O.D.S. (Output Driver Strength).
196 	 */
197 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
198 		       ram_address + (0x1 << ba_off));
199 
200 	/*
201 	 * Write a one to the DLL bit (enable DLL reset) in the MPDDRC
202 	 * Configuration Register.
203 	 */
204 
205 	/* A Mode Register Set (MRS) cycle is issued to reset DLL. */
206 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_LMR_CMD, ram_address);
207 
208 	udelay(50);
209 
210 	/*
211 	 * A Calibration command (MRS) is issued to calibrate RTT and RON
212 	 * values for the Process Voltage Temperature (PVT).
213 	 */
214 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_DEEP_CMD, ram_address);
215 
216 	/* A Normal Mode command is provided. */
217 	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NORMAL_CMD, ram_address);
218 
219 	/* Perform a write access to any DDR3-SDRAM address. */
220 	writel(0, ram_address);
221 
222 	/*
223 	 * Write the refresh rate into the COUNT field in the MPDDRC
224 	 * Refresh Timer Register (MPDDRC_RTR):
225 	 */
226 	writel(mpddr_value->rtr, &mpddr->rtr);
227 
228 	return 0;
229 }
230