1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * sunxi DRAM controller initialization
4 * (C) Copyright 2012 Henrik Nordstrom <henrik@henriknordstrom.net>
5 * (C) Copyright 2013 Luke Kenneth Casson Leighton <lkcl@lkcl.net>
6 *
7 * Based on sun4i Linux kernel sources mach-sunxi/pm/standby/dram*.c
8 * and earlier U-Boot Allwinner A10 SPL work
9 *
10 * (C) Copyright 2007-2012
11 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
12 * Berg Xing <bergxing@allwinnertech.com>
13 * Tom Cubie <tangliang@allwinnertech.com>
14 */
15
16/*
17 * Unfortunately the only documentation we have on the sun7i DRAM
18 * controller is Allwinner boot0 + boot1 code, and that code uses
19 * magic numbers & shifts with no explanations. Hence this code is
20 * rather undocumented and full of magic.
21 */
22
23#include <init.h>
24#include <asm/io.h>
25#include <asm/arch/clock.h>
26#include <asm/arch/dram.h>
27#include <asm/arch/timer.h>
28#include <asm/arch/sys_proto.h>
29#include <linux/delay.h>
30
31#define CPU_CFG_CHIP_VER(n) ((n) << 6)
32#define CPU_CFG_CHIP_VER_MASK CPU_CFG_CHIP_VER(0x3)
33#define CPU_CFG_CHIP_REV_A 0x0
34#define CPU_CFG_CHIP_REV_C1 0x1
35#define CPU_CFG_CHIP_REV_C2 0x2
36#define CPU_CFG_CHIP_REV_B 0x3
37
38/*
39 * Wait up to 1s for mask to be clear in given reg.
40 */
41static inline void await_bits_clear(u32 *reg, u32 mask)
42{
43	mctl_await_completion(reg, mask, 0);
44}
45
46/*
47 * Wait up to 1s for mask to be set in given reg.
48 */
49static inline void await_bits_set(u32 *reg, u32 mask)
50{
51	mctl_await_completion(reg, mask, mask);
52}
53
54/*
55 * This performs the external DRAM reset by driving the RESET pin low and
56 * then high again. According to the DDR3 spec, the RESET pin needs to be
57 * kept low for at least 200 us.
58 */
59static void mctl_ddr3_reset(void)
60{
61	struct sunxi_dram_reg *dram =
62			(struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
63
64#ifdef CONFIG_MACH_SUN4I
65	struct sunxi_timer_reg *timer =
66			(struct sunxi_timer_reg *)SUNXI_TIMER_BASE;
67	u32 reg_val;
68
69	writel(0, &timer->cpu_cfg);
70	reg_val = readl(&timer->cpu_cfg);
71
72	if ((reg_val & CPU_CFG_CHIP_VER_MASK) !=
73	    CPU_CFG_CHIP_VER(CPU_CFG_CHIP_REV_A)) {
74		setbits_le32(&dram->mcr, DRAM_MCR_RESET);
75		udelay(200);
76		clrbits_le32(&dram->mcr, DRAM_MCR_RESET);
77	} else
78#endif
79	{
80		clrbits_le32(&dram->mcr, DRAM_MCR_RESET);
81		udelay(200);
82		setbits_le32(&dram->mcr, DRAM_MCR_RESET);
83	}
84	/* After the RESET pin is de-asserted, the DDR3 spec requires to wait
85	 * for additional 500 us before driving the CKE pin (Clock Enable)
86	 * high. The duration of this delay can be configured in the SDR_IDCR
87	 * (Initialization Delay Configuration Register) and applied
88	 * automatically by the DRAM controller during the DDR3 initialization
89	 * step. But SDR_IDCR has limited range on sun4i/sun5i hardware and
90	 * can't provide sufficient delay at DRAM clock frequencies higher than
91	 * 524 MHz (while Allwinner A13 supports DRAM clock frequency up to
92	 * 533 MHz according to the datasheet). Additionally, there is no
93	 * official documentation for the SDR_IDCR register anywhere, and
94	 * there is always a chance that we are interpreting it wrong.
95	 * Better be safe than sorry, so add an explicit delay here. */
96	udelay(500);
97}
98
99static void mctl_set_drive(void)
100{
101	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
102
103#ifdef CONFIG_MACH_SUN7I
104	clrsetbits_le32(&dram->mcr, DRAM_MCR_MODE_NORM(0x3) | (0x3 << 28),
105#else
106	clrsetbits_le32(&dram->mcr, DRAM_MCR_MODE_NORM(0x3),
107#endif
108			DRAM_MCR_MODE_EN(0x3) |
109			0xffc);
110}
111
112static void mctl_itm_disable(void)
113{
114	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
115
116	clrsetbits_le32(&dram->ccr, DRAM_CCR_INIT, DRAM_CCR_ITM_OFF);
117}
118
119static void mctl_itm_enable(void)
120{
121	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
122
123	clrbits_le32(&dram->ccr, DRAM_CCR_ITM_OFF);
124}
125
126static void mctl_itm_reset(void)
127{
128	mctl_itm_disable();
129	udelay(1); /* ITM reset needs a bit of delay */
130	mctl_itm_enable();
131	udelay(1);
132}
133
134static void mctl_enable_dll0(u32 phase)
135{
136	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
137
138	clrsetbits_le32(&dram->dllcr[0], 0x3f << 6,
139			((phase >> 16) & 0x3f) << 6);
140	clrsetbits_le32(&dram->dllcr[0], DRAM_DLLCR_NRESET, DRAM_DLLCR_DISABLE);
141	udelay(2);
142
143	clrbits_le32(&dram->dllcr[0], DRAM_DLLCR_NRESET | DRAM_DLLCR_DISABLE);
144	udelay(22);
145
146	clrsetbits_le32(&dram->dllcr[0], DRAM_DLLCR_DISABLE, DRAM_DLLCR_NRESET);
147	udelay(22);
148}
149
150/* Get the number of DDR byte lanes */
151static u32 mctl_get_number_of_lanes(void)
152{
153	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
154	if ((readl(&dram->dcr) & DRAM_DCR_BUS_WIDTH_MASK) ==
155				DRAM_DCR_BUS_WIDTH(DRAM_DCR_BUS_WIDTH_32BIT))
156		return 4;
157	else
158		return 2;
159}
160
161/*
162 * Note: This differs from pm/standby in that it checks the bus width
163 */
164static void mctl_enable_dllx(u32 phase)
165{
166	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
167	u32 i, number_of_lanes;
168
169	number_of_lanes = mctl_get_number_of_lanes();
170
171	for (i = 1; i <= number_of_lanes; i++) {
172		clrsetbits_le32(&dram->dllcr[i], 0xf << 14,
173				(phase & 0xf) << 14);
174		clrsetbits_le32(&dram->dllcr[i], DRAM_DLLCR_NRESET,
175				DRAM_DLLCR_DISABLE);
176		phase >>= 4;
177	}
178	udelay(2);
179
180	for (i = 1; i <= number_of_lanes; i++)
181		clrbits_le32(&dram->dllcr[i], DRAM_DLLCR_NRESET |
182			     DRAM_DLLCR_DISABLE);
183	udelay(22);
184
185	for (i = 1; i <= number_of_lanes; i++)
186		clrsetbits_le32(&dram->dllcr[i], DRAM_DLLCR_DISABLE,
187				DRAM_DLLCR_NRESET);
188	udelay(22);
189}
190
191static u32 hpcr_value[32] = {
192#ifdef CONFIG_MACH_SUN5I
193	0, 0, 0, 0,
194	0, 0, 0, 0,
195	0, 0, 0, 0,
196	0, 0, 0, 0,
197	0x1031, 0x1031, 0x0735, 0x1035,
198	0x1035, 0x0731, 0x1031, 0,
199	0x0301, 0x0301, 0x0301, 0x0301,
200	0x0301, 0x0301, 0x0301, 0
201#endif
202#ifdef CONFIG_MACH_SUN4I
203	0x0301, 0x0301, 0x0301, 0x0301,
204	0x0301, 0x0301, 0, 0,
205	0, 0, 0, 0,
206	0, 0, 0, 0,
207	0x1031, 0x1031, 0x0735, 0x5031,
208	0x1035, 0x0731, 0x1031, 0x0735,
209	0x1035, 0x1031, 0x0731, 0x1035,
210	0x1031, 0x0301, 0x0301, 0x0731
211#endif
212#ifdef CONFIG_MACH_SUN7I
213	0x0301, 0x0301, 0x0301, 0x0301,
214	0x0301, 0x0301, 0x0301, 0x0301,
215	0, 0, 0, 0,
216	0, 0, 0, 0,
217	0x1031, 0x1031, 0x0735, 0x1035,
218	0x1035, 0x0731, 0x1031, 0x0735,
219	0x1035, 0x1031, 0x0731, 0x1035,
220	0x0001, 0x1031, 0, 0x1031
221	/* last row differs from boot0 source table
222	 * 0x1031, 0x0301, 0x0301, 0x0731
223	 * but boot0 code skips #28 and #30, and sets #29 and #31 to the
224	 * value from #28 entry (0x1031)
225	 */
226#endif
227};
228
229static void mctl_configure_hostport(void)
230{
231	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
232	u32 i;
233
234	for (i = 0; i < 32; i++)
235		writel(hpcr_value[i], &dram->hpcr[i]);
236}
237
238static void mctl_setup_dram_clock(u32 clk, u32 mbus_clk)
239{
240	u32 reg_val;
241	struct sunxi_ccm_reg *ccm = (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
242	u32 pll5p_clk, pll6x_clk;
243	u32 pll5p_div, pll6x_div;
244	u32 pll5p_rate, pll6x_rate;
245
246	/* setup DRAM PLL */
247	reg_val = readl(&ccm->pll5_cfg);
248	reg_val &= ~CCM_PLL5_CTRL_M_MASK;		/* set M to 0 (x1) */
249	reg_val &= ~CCM_PLL5_CTRL_K_MASK;		/* set K to 0 (x1) */
250	reg_val &= ~CCM_PLL5_CTRL_N_MASK;		/* set N to 0 (x0) */
251	reg_val &= ~CCM_PLL5_CTRL_P_MASK;		/* set P to 0 (x1) */
252#ifdef CONFIG_OLD_SUNXI_KERNEL_COMPAT
253	/* Old kernels are hardcoded to P=1 (divide by 2) */
254	reg_val |= CCM_PLL5_CTRL_P(1);
255#endif
256	if (clk >= 540 && clk < 552) {
257		/* dram = 540MHz */
258		reg_val |= CCM_PLL5_CTRL_M(CCM_PLL5_CTRL_M_X(2));
259		reg_val |= CCM_PLL5_CTRL_K(CCM_PLL5_CTRL_K_X(3));
260		reg_val |= CCM_PLL5_CTRL_N(CCM_PLL5_CTRL_N_X(15));
261	} else if (clk >= 512 && clk < 528) {
262		/* dram = 512MHz */
263		reg_val |= CCM_PLL5_CTRL_M(CCM_PLL5_CTRL_M_X(3));
264		reg_val |= CCM_PLL5_CTRL_K(CCM_PLL5_CTRL_K_X(4));
265		reg_val |= CCM_PLL5_CTRL_N(CCM_PLL5_CTRL_N_X(16));
266	} else if (clk >= 496 && clk < 504) {
267		/* dram = 496MHz */
268		reg_val |= CCM_PLL5_CTRL_M(CCM_PLL5_CTRL_M_X(3));
269		reg_val |= CCM_PLL5_CTRL_K(CCM_PLL5_CTRL_K_X(2));
270		reg_val |= CCM_PLL5_CTRL_N(CCM_PLL5_CTRL_N_X(31));
271	} else if (clk >= 468 && clk < 480) {
272		/* dram = 468MHz */
273		reg_val |= CCM_PLL5_CTRL_M(CCM_PLL5_CTRL_M_X(2));
274		reg_val |= CCM_PLL5_CTRL_K(CCM_PLL5_CTRL_K_X(3));
275		reg_val |= CCM_PLL5_CTRL_N(CCM_PLL5_CTRL_N_X(13));
276	} else if (clk >= 396 && clk < 408) {
277		/* dram = 396MHz */
278		reg_val |= CCM_PLL5_CTRL_M(CCM_PLL5_CTRL_M_X(2));
279		reg_val |= CCM_PLL5_CTRL_K(CCM_PLL5_CTRL_K_X(3));
280		reg_val |= CCM_PLL5_CTRL_N(CCM_PLL5_CTRL_N_X(11));
281	} else {
282		/* any other frequency that is a multiple of 24 */
283		reg_val |= CCM_PLL5_CTRL_M(CCM_PLL5_CTRL_M_X(2));
284		reg_val |= CCM_PLL5_CTRL_K(CCM_PLL5_CTRL_K_X(2));
285		reg_val |= CCM_PLL5_CTRL_N(CCM_PLL5_CTRL_N_X(clk / 24));
286	}
287	reg_val &= ~CCM_PLL5_CTRL_VCO_GAIN;		/* PLL VCO Gain off */
288	reg_val |= CCM_PLL5_CTRL_EN;			/* PLL On */
289	writel(reg_val, &ccm->pll5_cfg);
290	udelay(5500);
291
292	setbits_le32(&ccm->pll5_cfg, CCM_PLL5_CTRL_DDR_CLK);
293
294#if defined(CONFIG_MACH_SUN4I) || defined(CONFIG_MACH_SUN7I)
295	/* reset GPS */
296	clrbits_le32(&ccm->gps_clk_cfg, CCM_GPS_CTRL_RESET | CCM_GPS_CTRL_GATE);
297	setbits_le32(&ccm->ahb_gate0, CCM_AHB_GATE_GPS);
298	udelay(1);
299	clrbits_le32(&ccm->ahb_gate0, CCM_AHB_GATE_GPS);
300#endif
301
302	/* setup MBUS clock */
303	if (!mbus_clk)
304		mbus_clk = 300;
305
306	/* PLL5P and PLL6 are the potential clock sources for MBUS */
307	pll6x_clk = clock_get_pll6() / 1000000;
308#ifdef CONFIG_MACH_SUN7I
309	pll6x_clk *= 2; /* sun7i uses PLL6*2, sun5i uses just PLL6 */
310#endif
311	pll5p_clk = clock_get_pll5p() / 1000000;
312	pll6x_div = DIV_ROUND_UP(pll6x_clk, mbus_clk);
313	pll5p_div = DIV_ROUND_UP(pll5p_clk, mbus_clk);
314	pll6x_rate = pll6x_clk / pll6x_div;
315	pll5p_rate = pll5p_clk / pll5p_div;
316
317	if (pll6x_div <= 16 && pll6x_rate > pll5p_rate) {
318		/* use PLL6 as the MBUS clock source */
319		reg_val = CCM_MBUS_CTRL_GATE |
320			  CCM_MBUS_CTRL_CLK_SRC(CCM_MBUS_CTRL_CLK_SRC_PLL6) |
321			  CCM_MBUS_CTRL_N(CCM_MBUS_CTRL_N_X(1)) |
322			  CCM_MBUS_CTRL_M(CCM_MBUS_CTRL_M_X(pll6x_div));
323	} else if (pll5p_div <= 16) {
324		/* use PLL5P as the MBUS clock source */
325		reg_val = CCM_MBUS_CTRL_GATE |
326			  CCM_MBUS_CTRL_CLK_SRC(CCM_MBUS_CTRL_CLK_SRC_PLL5) |
327			  CCM_MBUS_CTRL_N(CCM_MBUS_CTRL_N_X(1)) |
328			  CCM_MBUS_CTRL_M(CCM_MBUS_CTRL_M_X(pll5p_div));
329	} else {
330		panic("Bad mbus_clk\n");
331	}
332	writel(reg_val, &ccm->mbus_clk_cfg);
333
334	/*
335	 * open DRAMC AHB & DLL register clock
336	 * close it first
337	 */
338#if defined(CONFIG_MACH_SUN5I) || defined(CONFIG_MACH_SUN7I)
339	clrbits_le32(&ccm->ahb_gate0, CCM_AHB_GATE_SDRAM | CCM_AHB_GATE_DLL);
340#else
341	clrbits_le32(&ccm->ahb_gate0, CCM_AHB_GATE_SDRAM);
342#endif
343	udelay(22);
344
345	/* then open it */
346#if defined(CONFIG_MACH_SUN5I) || defined(CONFIG_MACH_SUN7I)
347	setbits_le32(&ccm->ahb_gate0, CCM_AHB_GATE_SDRAM | CCM_AHB_GATE_DLL);
348#else
349	setbits_le32(&ccm->ahb_gate0, CCM_AHB_GATE_SDRAM);
350#endif
351	udelay(22);
352}
353
354/*
355 * The data from rslrX and rdgrX registers (X=rank) is stored
356 * in a single 32-bit value using the following format:
357 *   bits [31:26] - DQS gating system latency for byte lane 3
358 *   bits [25:24] - DQS gating phase select for byte lane 3
359 *   bits [23:18] - DQS gating system latency for byte lane 2
360 *   bits [17:16] - DQS gating phase select for byte lane 2
361 *   bits [15:10] - DQS gating system latency for byte lane 1
362 *   bits [ 9:8 ] - DQS gating phase select for byte lane 1
363 *   bits [ 7:2 ] - DQS gating system latency for byte lane 0
364 *   bits [ 1:0 ] - DQS gating phase select for byte lane 0
365 */
366static void mctl_set_dqs_gating_delay(int rank, u32 dqs_gating_delay)
367{
368	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
369	u32 lane, number_of_lanes = mctl_get_number_of_lanes();
370	/* rank0 gating system latency (3 bits per lane: cycles) */
371	u32 slr = readl(rank == 0 ? &dram->rslr0 : &dram->rslr1);
372	/* rank0 gating phase select (2 bits per lane: 90, 180, 270, 360) */
373	u32 dgr = readl(rank == 0 ? &dram->rdgr0 : &dram->rdgr1);
374	for (lane = 0; lane < number_of_lanes; lane++) {
375		u32 tmp = dqs_gating_delay >> (lane * 8);
376		slr &= ~(7 << (lane * 3));
377		slr |= ((tmp >> 2) & 7) << (lane * 3);
378		dgr &= ~(3 << (lane * 2));
379		dgr |= (tmp & 3) << (lane * 2);
380	}
381	writel(slr, rank == 0 ? &dram->rslr0 : &dram->rslr1);
382	writel(dgr, rank == 0 ? &dram->rdgr0 : &dram->rdgr1);
383}
384
385static int dramc_scan_readpipe(void)
386{
387	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
388	u32 reg_val;
389
390	/* data training trigger */
391	clrbits_le32(&dram->csr, DRAM_CSR_FAILED);
392	setbits_le32(&dram->ccr, DRAM_CCR_DATA_TRAINING);
393
394	/* check whether data training process has completed */
395	await_bits_clear(&dram->ccr, DRAM_CCR_DATA_TRAINING);
396
397	/* check data training result */
398	reg_val = readl(&dram->csr);
399	if (reg_val & DRAM_CSR_FAILED)
400		return -1;
401
402	return 0;
403}
404
405static void dramc_clock_output_en(u32 on)
406{
407#if defined(CONFIG_MACH_SUN5I) || defined(CONFIG_MACH_SUN7I)
408	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
409
410	if (on)
411		setbits_le32(&dram->mcr, DRAM_MCR_DCLK_OUT);
412	else
413		clrbits_le32(&dram->mcr, DRAM_MCR_DCLK_OUT);
414#endif
415#ifdef CONFIG_MACH_SUN4I
416	struct sunxi_ccm_reg *ccm = (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
417	if (on)
418		setbits_le32(&ccm->dram_clk_gate, CCM_DRAM_CTRL_DCLK_OUT);
419	else
420		clrbits_le32(&ccm->dram_clk_gate, CCM_DRAM_CTRL_DCLK_OUT);
421#endif
422}
423
424/* tRFC in nanoseconds for different densities (from the DDR3 spec) */
425static const u16 tRFC_DDR3_table[6] = {
426	/* 256Mb    512Mb    1Gb      2Gb      4Gb      8Gb */
427	   90,      90,      110,     160,     300,     350
428};
429
430static void dramc_set_autorefresh_cycle(u32 clk, u32 density)
431{
432	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
433	u32 tRFC, tREFI;
434
435	tRFC = (tRFC_DDR3_table[density] * clk + 999) / 1000;
436	tREFI = (7987 * clk) >> 10;	/* <= 7.8us */
437
438	writel(DRAM_DRR_TREFI(tREFI) | DRAM_DRR_TRFC(tRFC), &dram->drr);
439}
440
441/* Calculate the value for A11, A10, A9 bits in MR0 (write recovery) */
442static u32 ddr3_write_recovery(u32 clk)
443{
444	u32 twr_ns = 15; /* DDR3 spec says that it is 15ns for all speed bins */
445	u32 twr_ck = (twr_ns * clk + 999) / 1000;
446	if (twr_ck < 5)
447		return 1;
448	else if (twr_ck <= 8)
449		return twr_ck - 4;
450	else if (twr_ck <= 10)
451		return 5;
452	else
453		return 6;
454}
455
456/*
457 * If the dram->ppwrsctl (SDR_DPCR) register has the lowest bit set to 1, this
458 * means that DRAM is currently in self-refresh mode and retaining the old
459 * data. Since we have no idea what to do in this situation yet, just set this
460 * register to 0 and initialize DRAM in the same way as on any normal reboot
461 * (discarding whatever was stored there).
462 *
463 * Note: on sun7i hardware, the highest 16 bits need to be set to 0x1651 magic
464 * value for this write operation to have any effect. On sun5i hadware this
465 * magic value is not necessary. And on sun4i hardware the writes to this
466 * register seem to have no effect at all.
467 */
468static void mctl_disable_power_save(void)
469{
470	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
471	writel(0x16510000, &dram->ppwrsctl);
472}
473
474/*
475 * After the DRAM is powered up or reset, the DDR3 spec requires to wait at
476 * least 500 us before driving the CKE pin (Clock Enable) high. The dram->idct
477 * (SDR_IDCR) register appears to configure this delay, which gets applied
478 * right at the time when the DRAM initialization is activated in the
479 * 'mctl_ddr3_initialize' function.
480 */
481static void mctl_set_cke_delay(void)
482{
483	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
484
485	/* The CKE delay is represented in DRAM clock cycles, multiplied by N
486	 * (where N=2 for sun4i/sun5i and N=3 for sun7i). Here it is set to
487	 * the maximum possible value 0x1ffff, just like in the Allwinner's
488	 * boot0 bootloader. The resulting delay value is somewhere between
489	 * ~0.4 ms (sun5i with 648 MHz DRAM clock speed) and ~1.1 ms (sun7i
490	 * with 360 MHz DRAM clock speed). */
491	setbits_le32(&dram->idcr, 0x1ffff);
492}
493
494/*
495 * This triggers the DRAM initialization. It performs sending the mode registers
496 * to the DRAM among other things. Very likely the ZQCL command is also getting
497 * executed (to do the initial impedance calibration on the DRAM side of the
498 * wire). The memory controller and the PHY must be already configured before
499 * calling this function.
500 */
501static void mctl_ddr3_initialize(void)
502{
503	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
504	setbits_le32(&dram->ccr, DRAM_CCR_INIT);
505	await_bits_clear(&dram->ccr, DRAM_CCR_INIT);
506}
507
508/*
509 * Perform impedance calibration on the DRAM controller side of the wire.
510 */
511static void mctl_set_impedance(u32 zq, bool odt_en)
512{
513	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
514	u32 reg_val;
515	u32 zprog = zq & 0xFF, zdata = (zq >> 8) & 0xFFFFF;
516
517#ifndef CONFIG_MACH_SUN7I
518	/* Appears that some kind of automatically initiated default
519	 * ZQ calibration is already in progress at this point on sun4i/sun5i
520	 * hardware, but not on sun7i. So it is reasonable to wait for its
521	 * completion before doing anything else. */
522	await_bits_set(&dram->zqsr, DRAM_ZQSR_ZDONE);
523#endif
524
525	/* ZQ calibration is not really useful unless ODT is enabled */
526	if (!odt_en)
527		return;
528
529#ifdef CONFIG_MACH_SUN7I
530	/* Enabling ODT in SDR_IOCR on sun7i hardware results in a deadlock
531	 * unless bit 24 is set in SDR_ZQCR1. Not much is known about the
532	 * SDR_ZQCR1 register, but there are hints indicating that it might
533	 * be related to periodic impedance re-calibration. This particular
534	 * magic value is borrowed from the Allwinner boot0 bootloader, and
535	 * using it helps to avoid troubles */
536	writel((1 << 24) | (1 << 1), &dram->zqcr1);
537#endif
538
539	/* Needed at least for sun5i, because it does not self clear there */
540	clrbits_le32(&dram->zqcr0, DRAM_ZQCR0_ZCAL);
541
542	if (zdata) {
543		/* Set the user supplied impedance data */
544		reg_val = DRAM_ZQCR0_ZDEN | zdata;
545		writel(reg_val, &dram->zqcr0);
546		/* no need to wait, this takes effect immediately */
547	} else {
548		/* Do the calibration using the external resistor */
549		reg_val = DRAM_ZQCR0_ZCAL | DRAM_ZQCR0_IMP_DIV(zprog);
550		writel(reg_val, &dram->zqcr0);
551		/* Wait for the new impedance configuration to settle */
552		await_bits_set(&dram->zqsr, DRAM_ZQSR_ZDONE);
553	}
554
555	/* Needed at least for sun5i, because it does not self clear there */
556	clrbits_le32(&dram->zqcr0, DRAM_ZQCR0_ZCAL);
557
558	/* Set I/O configure register */
559	writel(DRAM_IOCR_ODT_EN, &dram->iocr);
560}
561
562static unsigned long dramc_init_helper(struct dram_para *para)
563{
564	struct sunxi_dram_reg *dram = (struct sunxi_dram_reg *)SUNXI_DRAMC_BASE;
565	u32 reg_val;
566	u32 density;
567	int ret_val;
568
569	/*
570	 * only single rank DDR3 is supported by this code even though the
571	 * hardware can theoretically support DDR2 and up to two ranks
572	 */
573	if (para->type != DRAM_MEMORY_TYPE_DDR3 || para->rank_num != 1)
574		return 0;
575
576	/* setup DRAM relative clock */
577	mctl_setup_dram_clock(para->clock, para->mbus_clock);
578
579	/* Disable any pad power save control */
580	mctl_disable_power_save();
581
582	mctl_set_drive();
583
584	/* dram clock off */
585	dramc_clock_output_en(0);
586
587#ifdef CONFIG_MACH_SUN4I
588	/* select dram controller 1 */
589	writel(DRAM_CSEL_MAGIC, &dram->csel);
590#endif
591
592	mctl_itm_disable();
593	mctl_enable_dll0(para->tpr3);
594
595	/* configure external DRAM */
596	reg_val = DRAM_DCR_TYPE_DDR3;
597	reg_val |= DRAM_DCR_IO_WIDTH(para->io_width >> 3);
598
599	if (para->density == 256)
600		density = DRAM_DCR_CHIP_DENSITY_256M;
601	else if (para->density == 512)
602		density = DRAM_DCR_CHIP_DENSITY_512M;
603	else if (para->density == 1024)
604		density = DRAM_DCR_CHIP_DENSITY_1024M;
605	else if (para->density == 2048)
606		density = DRAM_DCR_CHIP_DENSITY_2048M;
607	else if (para->density == 4096)
608		density = DRAM_DCR_CHIP_DENSITY_4096M;
609	else if (para->density == 8192)
610		density = DRAM_DCR_CHIP_DENSITY_8192M;
611	else
612		density = DRAM_DCR_CHIP_DENSITY_256M;
613
614	reg_val |= DRAM_DCR_CHIP_DENSITY(density);
615	reg_val |= DRAM_DCR_BUS_WIDTH((para->bus_width >> 3) - 1);
616	reg_val |= DRAM_DCR_RANK_SEL(para->rank_num - 1);
617	reg_val |= DRAM_DCR_CMD_RANK_ALL;
618	reg_val |= DRAM_DCR_MODE(DRAM_DCR_MODE_INTERLEAVE);
619	writel(reg_val, &dram->dcr);
620
621	dramc_clock_output_en(1);
622
623	mctl_set_impedance(para->zq, para->odt_en);
624
625	mctl_set_cke_delay();
626
627	mctl_ddr3_reset();
628
629	udelay(1);
630
631	await_bits_clear(&dram->ccr, DRAM_CCR_INIT);
632
633	mctl_enable_dllx(para->tpr3);
634
635	/* set refresh period */
636	dramc_set_autorefresh_cycle(para->clock, density);
637
638	/* set timing parameters */
639	writel(para->tpr0, &dram->tpr0);
640	writel(para->tpr1, &dram->tpr1);
641	writel(para->tpr2, &dram->tpr2);
642
643	reg_val = DRAM_MR_BURST_LENGTH(0x0);
644#if (defined(CONFIG_MACH_SUN5I) || defined(CONFIG_MACH_SUN7I))
645	reg_val |= DRAM_MR_POWER_DOWN;
646#endif
647	reg_val |= DRAM_MR_CAS_LAT(para->cas - 4);
648	reg_val |= DRAM_MR_WRITE_RECOVERY(ddr3_write_recovery(para->clock));
649	writel(reg_val, &dram->mr);
650
651	writel(para->emr1, &dram->emr);
652	writel(para->emr2, &dram->emr2);
653	writel(para->emr3, &dram->emr3);
654
655	/* disable drift compensation and set passive DQS window mode */
656	clrsetbits_le32(&dram->ccr, DRAM_CCR_DQS_DRIFT_COMP, DRAM_CCR_DQS_GATE);
657
658#ifdef CONFIG_MACH_SUN7I
659	/* Command rate timing mode 2T & 1T */
660	if (para->tpr4 & 0x1)
661		setbits_le32(&dram->ccr, DRAM_CCR_COMMAND_RATE_1T);
662#endif
663	/* initialize external DRAM */
664	mctl_ddr3_initialize();
665
666	/* scan read pipe value */
667	mctl_itm_enable();
668
669	/* Hardware DQS gate training */
670	ret_val = dramc_scan_readpipe();
671
672	if (ret_val < 0)
673		return 0;
674
675	/* allow to override the DQS training results with a custom delay */
676	if (para->dqs_gating_delay)
677		mctl_set_dqs_gating_delay(0, para->dqs_gating_delay);
678
679	/* set the DQS gating window type */
680	if (para->active_windowing)
681		clrbits_le32(&dram->ccr, DRAM_CCR_DQS_GATE);
682	else
683		setbits_le32(&dram->ccr, DRAM_CCR_DQS_GATE);
684
685	mctl_itm_reset();
686
687	/* configure all host port */
688	mctl_configure_hostport();
689
690	return get_ram_size((long *)PHYS_SDRAM_0, PHYS_SDRAM_0_SIZE);
691}
692
693unsigned long dramc_init(struct dram_para *para)
694{
695	unsigned long dram_size, actual_density;
696
697	/* If the dram configuration is not provided, use a default */
698	if (!para)
699		return 0;
700
701	/* if everything is known, then autodetection is not necessary */
702	if (para->io_width && para->bus_width && para->density)
703		return dramc_init_helper(para);
704
705	/* try to autodetect the DRAM bus width and density */
706	para->io_width  = 16;
707	para->bus_width = 32;
708#if defined(CONFIG_MACH_SUN4I) || defined(CONFIG_MACH_SUN5I)
709	/* only A0-A14 address lines on A10/A13, limiting max density to 4096 */
710	para->density = 4096;
711#else
712	/* all A0-A15 address lines on A20, which allow density 8192 */
713	para->density = 8192;
714#endif
715
716	dram_size = dramc_init_helper(para);
717	if (!dram_size) {
718		/* if 32-bit bus width failed, try 16-bit bus width instead */
719		para->bus_width = 16;
720		dram_size = dramc_init_helper(para);
721		if (!dram_size) {
722			/* if 16-bit bus width also failed, then bail out */
723			return dram_size;
724		}
725	}
726
727	/* check if we need to adjust the density */
728	actual_density = (dram_size >> 17) * para->io_width / para->bus_width;
729
730	if (actual_density != para->density) {
731		/* update the density and re-initialize DRAM again */
732		para->density = actual_density;
733		dram_size = dramc_init_helper(para);
734	}
735
736	return dram_size;
737}
738