1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * (C) Copyright 2018
4 * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
5 */
6
7/**
8 * enum ratio - Description of a core clock ratio
9 * @RAT_UNK:      Unknown ratio
10 * @RAT_BYP:      Bypass
11 * @RAT_1_TO_8:   Ratio 1:8
12 * @RAT_1_TO_4:   Ratio 1:4
13 * @RAT_1_TO_2:   Ratio 1:2
14 * @RAT_1_TO_1:   Ratio 1:1
15 * @RAT_1_5_TO_1: Ratio 1.5:1
16 * @RAT_2_TO_1:   Ratio 2:1
17 * @RAT_2_5_TO_1: Ratio 2.5:1
18 * @RAT_3_TO_1:   Ratio 3:1
19 */
20#include <linux/bitops.h>
21enum ratio {
22	RAT_UNK,
23	RAT_BYP,
24	RAT_1_TO_8,
25	RAT_1_TO_4,
26	RAT_1_TO_2,
27	RAT_1_TO_1,
28	RAT_1_5_TO_1,
29	RAT_2_TO_1,
30	RAT_2_5_TO_1,
31	RAT_3_TO_1
32};
33
34/**
35 * struct corecnf - Description for a core clock configuration
36 * @core_csb_ratio: Core clock frequency to CSB clock frequency ratio
37 * @vco_divider: VCO divider (Core VCO frequency = Core frequency * VCO divider)
38 */
39struct corecnf {
40	int core_csb_ratio;
41	int vco_divider;
42};
43
44/*
45 * Table with all valid Core CSB frequency ratio / VCO divider combinations as
46 * indexed by the COREPLL field of the SPMR
47 */
48static const struct corecnf corecnf_tab[] = {
49	{RAT_BYP, RAT_BYP},			/* 0x00 */
50	{RAT_BYP, RAT_BYP},			/* 0x01 */
51	{RAT_BYP, RAT_BYP},			/* 0x02 */
52	{RAT_BYP, RAT_BYP},			/* 0x03 */
53	{RAT_BYP, RAT_BYP},			/* 0x04 */
54	{RAT_BYP, RAT_BYP},			/* 0x05 */
55	{RAT_BYP, RAT_BYP},			/* 0x06 */
56	{RAT_BYP, RAT_BYP},			/* 0x07 */
57	{RAT_1_TO_1, RAT_1_TO_2},		/* 0x08 */
58	{RAT_1_TO_1, RAT_1_TO_4},		/* 0x09 */
59	{RAT_1_TO_1, RAT_1_TO_8},		/* 0x0A */
60	{RAT_1_TO_1, RAT_1_TO_8},		/* 0x0B */
61	{RAT_1_5_TO_1, RAT_1_TO_2},		/* 0x0C */
62	{RAT_1_5_TO_1, RAT_1_TO_4},		/* 0x0D */
63	{RAT_1_5_TO_1, RAT_1_TO_8},		/* 0x0E */
64	{RAT_1_5_TO_1, RAT_1_TO_8},		/* 0x0F */
65	{RAT_2_TO_1, RAT_1_TO_2},		/* 0x10 */
66	{RAT_2_TO_1, RAT_1_TO_4},		/* 0x11 */
67	{RAT_2_TO_1, RAT_1_TO_8},		/* 0x12 */
68	{RAT_2_TO_1, RAT_1_TO_8},		/* 0x13 */
69	{RAT_2_5_TO_1, RAT_1_TO_2},		/* 0x14 */
70	{RAT_2_5_TO_1, RAT_1_TO_4},		/* 0x15 */
71	{RAT_2_5_TO_1, RAT_1_TO_8},		/* 0x16 */
72	{RAT_2_5_TO_1, RAT_1_TO_8},		/* 0x17 */
73	{RAT_3_TO_1, RAT_1_TO_2},		/* 0x18 */
74	{RAT_3_TO_1, RAT_1_TO_4},		/* 0x19 */
75	{RAT_3_TO_1, RAT_1_TO_8},		/* 0x1A */
76	{RAT_3_TO_1, RAT_1_TO_8},		/* 0x1B */
77};
78
79/**
80 * enum reg_type - Register to read a field from
81 * @REG_SCCR: Use the SCCR register
82 * @REG_SPMR: Use the SPMR register
83 */
84enum reg_type {
85	REG_SCCR,
86	REG_SPMR,
87};
88
89/**
90 * enum mode_type - Description of how to read a specific frequency value
91 * @TYPE_INVALID: Unknown type, will provoke error
92 * @TYPE_SCCR_STANDARD:        Read a field from the SCCR register, and use it
93 *			       as a divider for the CSB clock to compute the
94 *			       frequency
95 * @TYPE_SCCR_ONOFF:           The field describes a bit flag that can turn the
96 *			       clock on or off
97 * @TYPE_SPMR_DIRECT_MULTIPLY: Read a field from the SPMR register, and use it
98 *			       as a multiplier for the CSB clock to compute the
99 *			       frequency
100 * @TYPE_SPECIAL:              The frequency is calculated in a non-standard way
101 */
102enum mode_type {
103	TYPE_INVALID = 0,
104	TYPE_SCCR_STANDARD,
105	TYPE_SCCR_ONOFF,
106	TYPE_SPMR_DIRECT_MULTIPLY,
107	TYPE_SPECIAL,
108};
109
110/* Map of each clock index to its human-readable name */
111static const char * const names[] = {
112	[MPC83XX_CLK_CORE] = "Core",
113	[MPC83XX_CLK_CSB] = "Coherent System Bus",
114	[MPC83XX_CLK_QE] = "QE",
115	[MPC83XX_CLK_BRG] = "BRG",
116	[MPC83XX_CLK_LBIU] = "Local Bus Controller",
117	[MPC83XX_CLK_LCLK] = "Local Bus",
118	[MPC83XX_CLK_MEM] = "DDR",
119	[MPC83XX_CLK_MEM_SEC] = "DDR Secondary",
120	[MPC83XX_CLK_ENC] = "SEC",
121	[MPC83XX_CLK_I2C1] = "I2C1",
122	[MPC83XX_CLK_I2C2] = "I2C2",
123	[MPC83XX_CLK_TDM] = "TDM",
124	[MPC83XX_CLK_SDHC] = "SDHC",
125	[MPC83XX_CLK_TSEC1] = "TSEC1",
126	[MPC83XX_CLK_TSEC2] = "TSEC2",
127	[MPC83XX_CLK_USBDR] = "USB DR",
128	[MPC83XX_CLK_USBMPH] = "USB MPH",
129	[MPC83XX_CLK_PCIEXP1] = "PCIEXP1",
130	[MPC83XX_CLK_PCIEXP2] = "PCIEXP2",
131	[MPC83XX_CLK_SATA] = "SATA",
132	[MPC83XX_CLK_DMAC] = "DMAC",
133	[MPC83XX_CLK_PCI] = "PCI",
134};
135
136/**
137 * struct clk_mode - Structure for clock mode descriiptions
138 * @low:  The low bit of the data field to read for this mode (may not apply to
139 *	  some modes)
140 * @high: The high bit of the data field to read for this mode (may not apply to
141 *	  some modes)
142 * @type: The type of the mode description (one of enum mode_type)
143 */
144struct clk_mode {
145	u8 low;
146	u8 high;
147	int type;
148};
149
150/**
151 * set_mode() - Build a clock mode description from data
152 * @mode: The clock mode description to be filled out
153 * @low:  The low bit of the data field to read for this mode (may not apply to
154 *	  some modes)
155 * @high: The high bit of the data field to read for this mode (may not apply to
156 *	  some modes)
157 * @type: The type of the mode description (one of enum mode_type)
158 *
159 * Clock mode descriptions are a succinct description of how to read a specific
160 * clock's rate from the hardware; usually by reading a specific field of a
161 * register, such a s the SCCR register, but some types use different methods
162 * for obtaining the clock rate.
163 */
164static void set_mode(struct clk_mode *mode, u8 low, u8 high, int type)
165{
166	mode->low = low;
167	mode->high = high;
168	mode->type = type;
169}
170
171/**
172 * retrieve_mode() - Get the clock mode description for a specific clock
173 * @clk:      The identifier of the clock for which the clock description should
174 *	      be retrieved
175 * @soc_type: The type of MPC83xx SoC for which the clock description should be
176 *	      retrieved
177 * @mode:     Pointer to a clk_mode structure to be filled with data for the
178 *	      clock
179 *
180 * Since some clock rate are stored in different places on different MPC83xx
181 * SoCs, the SoC type has to be supplied along with the clock's identifier.
182 *
183 * Return: 0 if OK, -ve on error
184 */
185static int retrieve_mode(int clk, int soc_type, struct clk_mode *mode)
186{
187	switch (clk) {
188	case MPC83XX_CLK_CORE:
189	case MPC83XX_CLK_CSB:
190	case MPC83XX_CLK_QE:
191	case MPC83XX_CLK_BRG:
192	case MPC83XX_CLK_LCLK:
193	case MPC83XX_CLK_I2C2:
194		set_mode(mode, 0, 0, TYPE_SPECIAL);
195		break;
196	case MPC83XX_CLK_MEM:
197		set_mode(mode, 1, 1, TYPE_SPMR_DIRECT_MULTIPLY);
198		break;
199	case MPC83XX_CLK_LBIU:
200	case MPC83XX_CLK_MEM_SEC:
201		set_mode(mode, 0, 0, TYPE_SPMR_DIRECT_MULTIPLY);
202		break;
203	case MPC83XX_CLK_TSEC1:
204		set_mode(mode, 0, 1, TYPE_SCCR_STANDARD);
205		break;
206	case MPC83XX_CLK_TSEC2:
207		if (soc_type == SOC_MPC8313) /* I2C and TSEC2 are the same register */
208			set_mode(mode, 2, 3, TYPE_SCCR_STANDARD);
209		else /* FIXME(mario.six@gdsys.cc): This has separate enable/disable bit! */
210			set_mode(mode, 0, 1, TYPE_SCCR_STANDARD);
211		break;
212	case MPC83XX_CLK_SDHC:
213		set_mode(mode, 4, 5, TYPE_SCCR_STANDARD);
214		break;
215	case MPC83XX_CLK_ENC:
216		set_mode(mode, 6, 7, TYPE_SCCR_STANDARD);
217		break;
218	case MPC83XX_CLK_I2C1:
219		if (soc_type == SOC_MPC8349)
220			set_mode(mode, 2, 3, TYPE_SCCR_STANDARD);
221		else /* I2C and ENC are the same register */
222			set_mode(mode, 6, 7, TYPE_SCCR_STANDARD);
223		break;
224	case MPC83XX_CLK_PCIEXP1:
225		set_mode(mode, 10, 11, TYPE_SCCR_STANDARD);
226		break;
227	case MPC83XX_CLK_PCIEXP2:
228		set_mode(mode, 12, 13, TYPE_SCCR_STANDARD);
229		break;
230	case MPC83XX_CLK_USBDR:
231		if (soc_type == SOC_MPC8313 || soc_type == SOC_MPC8349)
232			set_mode(mode, 10, 11, TYPE_SCCR_STANDARD);
233		else
234			set_mode(mode, 8, 9, TYPE_SCCR_STANDARD);
235		break;
236	case MPC83XX_CLK_USBMPH:
237		set_mode(mode, 8, 9, TYPE_SCCR_STANDARD);
238		break;
239	case MPC83XX_CLK_PCI:
240		set_mode(mode, 15, 15, TYPE_SCCR_ONOFF);
241		break;
242	case MPC83XX_CLK_DMAC:
243		set_mode(mode, 26, 27, TYPE_SCCR_STANDARD);
244		break;
245	case MPC83XX_CLK_SATA:
246		/* FIXME(mario.six@gdsys.cc): All SATA controllers must have the same clock ratio */
247		if (soc_type == SOC_MPC8379) {
248			set_mode(mode, 24, 25, TYPE_SCCR_STANDARD);
249			set_mode(mode, 26, 27, TYPE_SCCR_STANDARD);
250			set_mode(mode, 28, 29, TYPE_SCCR_STANDARD);
251			set_mode(mode, 30, 31, TYPE_SCCR_STANDARD);
252		} else {
253			set_mode(mode, 18, 19, TYPE_SCCR_STANDARD);
254			set_mode(mode, 20, 21, TYPE_SCCR_STANDARD);
255		}
256		break;
257	case MPC83XX_CLK_TDM:
258		set_mode(mode, 26, 27, TYPE_SCCR_STANDARD);
259		break;
260	default:
261		debug("%s: Unknown clock type %d on soc type %d\n",
262		      __func__, clk, soc_type);
263		set_mode(mode, 0, 0, TYPE_INVALID);
264		return -EINVAL;
265	}
266
267	return 0;
268}
269
270/**
271 * get_spmr() - Read the SPMR (System PLL Mode Register)
272 * @im: Pointer to the MPC83xx main register map in question
273 *
274 * Return: The SPMR value as a 32-bit number.
275 */
276static inline u32 get_spmr(immap_t *im)
277{
278	u32 res = in_be32(&im->clk.spmr);
279
280	return res;
281}
282
283/**
284 * get_sccr() - Read the SCCR (System Clock Control Register)
285 * @im: Pointer to the MPC83xx main register map in question
286 *
287 * Return: The SCCR value as a 32-bit number.
288 */
289static inline u32 get_sccr(immap_t *im)
290{
291	u32 res = in_be32(&im->clk.sccr);
292
293	return res;
294}
295
296/**
297 * get_lcrr() - Read the LCRR (Clock Ratio Register)
298 * @im: Pointer to the MPC83xx main register map in question
299 *
300 * Return: The LCRR value as a 32-bit number.
301 */
302static inline u32 get_lcrr(immap_t *im)
303{
304	u32 res = in_be32(&im->im_lbc.lcrr);
305
306	return res;
307}
308
309/**
310 * get_pci_sync_in() - Read the PCI synchronization clock speed
311 * @im: Pointer to the MPC83xx main register map in question
312 *
313 * Return: The PCI synchronization clock speed value as a 32-bit number.
314 */
315static inline u32 get_pci_sync_in(immap_t *im)
316{
317	u8 clkin_div;
318
319	clkin_div = (get_spmr(im) & SPMR_CKID) >> SPMR_CKID_SHIFT;
320	return get_board_sys_clk() / (1 + clkin_div);
321}
322
323/**
324 * get_csb_clk() - Read the CSB (Coheren System Bus) clock speed
325 * @im: Pointer to the MPC83xx main register map in question
326 *
327 * Return: The CSB clock speed value as a 32-bit number.
328 */
329static inline u32 get_csb_clk(immap_t *im)
330{
331	u8 spmf;
332
333	spmf = (get_spmr(im) & SPMR_SPMF) >> SPMR_SPMF_SHIFT;
334	return get_board_sys_clk() * spmf;
335}
336
337/**
338 * spmr_field() - Read a specific SPMR field
339 * @im:   Pointer to the MPC83xx main register map in question
340 * @mask: A bitmask that describes the bitfield to be read
341 *
342 * Return: The value of the bit field as a 32-bit number.
343 */
344static inline uint spmr_field(immap_t *im, u32 mask)
345{
346	/* Extract shift from bitmask */
347	uint shift = mask ? ffs(mask) - 1 : 0;
348
349	return (get_spmr(im) & mask) >> shift;
350}
351
352/**
353 * sccr_field() - Read a specific SCCR field
354 * @im:   Pointer to the MPC83xx main register map in question
355 * @mask: A bitmask that describes the bitfield to be read
356 *
357 * Return: The value of the bit field as a 32-bit number.
358 */
359static inline uint sccr_field(immap_t *im, u32 mask)
360{
361	/* Extract shift from bitmask */
362	uint shift = mask ? ffs(mask) - 1 : 0;
363
364	return (get_sccr(im) & mask) >> shift;
365}
366
367/**
368 * lcrr_field() - Read a specific LCRR field
369 * @im:   Pointer to the MPC83xx main register map in question
370 * @mask: A bitmask that describes the bitfield to be read
371 *
372 * Return: The value of the bit field as a 32-bit number.
373 */
374static inline uint lcrr_field(immap_t *im, u32 mask)
375{
376	/* Extract shift from bitmask */
377	uint shift = mask ? ffs(mask) - 1 : 0;
378
379	return (get_lcrr(im) & mask) >> shift;
380}
381