xref: /rk3399_ARM-atf/drivers/renesas/common/scif/scif.c (revision 67ad1ac8e77ca84ba03ea0e754f7b95c51cc796d)
1 /*
2  * Copyright (c) 2026, Renesas Electronics Corporation. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <stddef.h>
8 #include <stdint.h>
9 
10 #include <drivers/console.h>
11 #include <lib/mmio.h>
12 #include <lib/utils_def.h>
13 #include "scif.h"
14 
15 #include "cpg_registers.h"
16 #include "rcar_def.h"
17 #include "rcar_private.h"
18 
19 /* CPG */
20 #define CPG_MSTPSR2_SCIF0	BIT(7)
21 #define CPG_MSTPSR3_SCIF2	BIT(10)
22 
23 /* SCIF */
24 #define SCIF0_BASE		0xE6E60000UL
25 #define SCIF2_BASE		0xE6E88000UL
26 
27 /* SCIF */
28 #define SCIF_SCSMR		0x00
29 #define SCIF_SCBRR		0x04
30 #define SCIF_SCSCR		0x08
31 #define SCIF_SCFTDR		0x0C
32 #define SCIF_SCFSR		0x10
33 #define SCIF_SCFCR		0x18
34 #define SCIF_SCLSR		0x24
35 #define SCIF_DL			0x30
36 #define SCIF_CKS		0x34
37 
38 /* MODE pin */
39 #define MODEMR_MD12		BIT(12)
40 
41 #define SCBRR_115200BPS		17
42 #define SCBRR_115200BPS_D3_SSCG	16
43 #define SCBRR_115200BPS_E3_SSCG	15
44 #define SCBRR_230400BPS		8
45 
46 #define SCSCR_TE_EN		BIT(5)
47 #define SCSCR_RE_EN		BIT(4)
48 #define SCSCR_CKE_MASK		3
49 #define SCFSR_TEND_MASK		BIT(6)
50 #define SCFSR_TEND_TRANS_END	BIT(6)
51 #define SCSCR_CKE_INT_CLK	0
52 #define SCFCR_TFRST_EN		BIT(2)
53 #define SCFCR_RFRS_EN		BIT(1)
54 
55 int console_renesas_init(uintptr_t base_addr, uint32_t uart_clk,
56 		      uint32_t baud_rate)
57 {
58 	uint32_t prr = mmio_read_32(PRR);
59 	uint32_t base;
60 	int i;
61 
62 	if ((prr & PRR_PRODUCT_MASK) == PRR_PRODUCT_V3M) { /* V3M */
63 		base = SCIF0_BASE;
64 		/* Enable SCIF clock */
65 		mstpcr_write(CPG_SMSTPCR2, CPG_MSTPSR2, CPG_MSTPSR2_SCIF0);
66 	} else {
67 		base = SCIF2_BASE;
68 		/* Enable SCIF clock */
69 		mstpcr_write(CPG_SMSTPCR3, CPG_MSTPSR3, CPG_MSTPSR3_SCIF2);
70 	}
71 
72 	scif_console_set_regs(base + SCIF_SCFSR, base + SCIF_SCFTDR);
73 
74 	/* Clear bits TE and RE in SCSCR to 0 */
75 	mmio_write_16(base + SCIF_SCSCR, 0);
76 
77 	/* Set bits TFRST and RFRST in SCFCR to 1 */
78 	mmio_clrsetbits_16(base + SCIF_SCFCR,
79 			   SCFCR_TFRST_EN | SCFCR_RFRS_EN,
80 			   SCFCR_TFRST_EN | SCFCR_RFRS_EN);
81 
82 	/*
83 	 * Read flags of ER, DR, BRK, and RDF in SCFSR and those
84 	 * of TO and ORER in SCLSR, then clear them to 0.
85 	 */
86 	mmio_write_16(base + SCIF_SCFSR, 0);
87 	mmio_write_16(base + SCIF_SCLSR, 0);
88 
89 	/* Set bits CKE[1:0] in SCSCR */
90 	mmio_clrsetbits_16(base + SCIF_SCSCR, SCSCR_CKE_MASK,
91 			   SCSCR_CKE_INT_CLK);
92 
93 	/* Set data transfer format in SCSMR */
94 	mmio_write_16(base + SCIF_SCSMR, 0);
95 
96 	/* Set value in SCBRR */
97 	if ((prr & (PRR_PRODUCT_MASK | PRR_CUT_MASK)) == PRR_PRODUCT_H3_CUT10) {
98 		/* H3 ES 1.0 */
99 		mmio_write_8(base + SCIF_SCBRR, SCBRR_230400BPS);
100 	} else if (((prr & PRR_PRODUCT_MASK) == PRR_PRODUCT_D3) &&
101 		   (mmio_read_32(RST_MODEMR) & MODEMR_MD12)) {
102 		/* D3 with SSCG(MD12) ON */
103 		mmio_write_8(base + SCIF_SCBRR, SCBRR_115200BPS_D3_SSCG);
104 	} else if (((prr & PRR_PRODUCT_MASK) == PRR_PRODUCT_E3) &&
105 		   (mmio_read_32(RST_MODEMR) & MODEMR_MD12)) {
106 		/* E3 with SSCG(MD12) ON */
107 		mmio_write_8(base + SCIF_SCBRR, SCBRR_115200BPS_E3_SSCG);
108 	} else {
109 		/* H3/M3/M3N or when SSCG(MD12) is off in E3/D3 */
110 		mmio_write_8(base + SCIF_SCBRR, SCBRR_115200BPS);
111 	}
112 
113 	/* 1-bit interval elapsed */
114 	for (i = 0; i < 100; i++)
115 		asm volatile("nop");
116 
117 	/*
118 	 * Set bits RTRG[1:0], TTRG[1:0], and MCE in SCFCR
119 	 * Clear bits FRST and RFRST to 0
120 	 */
121 	mmio_write_16(base + SCIF_SCFCR, 0);
122 
123 	/* Set bits TE and RE in SCSCR to 1 */
124 	mmio_clrsetbits_16(base + SCIF_SCSCR, SCSCR_TE_EN | SCSCR_RE_EN,
125 			   SCSCR_TE_EN | SCSCR_RE_EN);
126 
127 	return 1;
128 }
129