summaryrefslogtreecommitdiff
path: root/src/soc/qualcomm/sc7180/qupv3_uart.c
blob: f9d99bb71e2acedfc278e6bb6e2c843b19e9bf1a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
/* SPDX-License-Identifier: GPL-2.0-only */

#include <assert.h>
#include <boot/coreboot_tables.h>
#include <console/uart.h>
#include <soc/clock.h>
#include <soc/qcom_qup_se.h>
#include <soc/qupv3_config.h>
#include <types.h>

/* COMMON STATUS/CONFIGURATION REGISTERS AND MASKS */

#define GENI_STATUS_M_GENI_CMD_ACTIVE_MASK	0x1
#define GENI_STATUS_S_GENI_CMD_ACTIVE_MASK	0x1000

#define UART_TX_WATERMARK_MARGIN	4	/* Represented in words */
#define UART_RX_WATERMARK_MARGIN	8	/* Represented in words */
#define UART_RX_RFR_WATERMARK_MARGIN	4	/* Represented in words */
#define UART_TX_BITS_PER_WORD	8
#define UART_RX_BITS_PER_WORD	8
#define START_UART_TX		0x8000000
#define START_UART_RX		0x8000000

/* UART FIFO Packing Configuration. */
/* Start_idx:0, direction:0, len:7, stop:0 */
#define UART_TX_PACK_VECTOR0	0x0E
/* Start_idx:8, direction:0, len:7, stop:0 */
#define UART_TX_PACK_VECTOR1	0x10E
/* Start_idx:16, direction:0, len:7, stop:0 */
#define UART_TX_PACK_VECTOR2	0x20E
/* Start_idx:24, direction:0, len:7, stop:1 */
#define UART_TX_PACK_VECTOR3	0x30F
/* Start_idx:0, direction:0, len:7, stop:1 */
#define UART_RX_PACK_VECTOR0	0xF
#define UART_RX_PACK_VECTOR2	0x00

void uart_tx_flush(int idx)
{
	struct qup_regs *regs = qup[idx].regs;

	while (read32(&regs->geni_status) &
	       GENI_STATUS_M_GENI_CMD_ACTIVE_MASK)
		;
}

void uart_init(int idx)
{
	struct qup_regs *regs = qup[idx].regs;
	unsigned int reg_value;
	unsigned int div, baud_rate, uart_freq;

	/*
	 * If the RX (secondary) sequencer is already active, it means the core
	 * has been already initialized in the previous stage. Skip
	 * configuration
	 */
	if (read32(&regs->geni_status) & GENI_STATUS_S_GENI_CMD_ACTIVE_MASK)
		return;

	qupv3_se_fw_load_and_init(idx, SE_PROTOCOL_UART, FIFO);
	clock_enable_qup(idx);

	reg_value = read32(&regs->geni_fw_revision_ro);
	reg_value &= GENI_FW_REVISION_RO_PROTOCOL_MASK;
	reg_value >>= GENI_FW_REVISION_RO_PROTOCOL_SHIFT;

	assert(reg_value == SE_PROTOCOL_UART);

	baud_rate = get_uart_baudrate();

	/* sc7180 requires 16 clock pulses to sample 1 bit of data */
	uart_freq = baud_rate * 16;

	div = DIV_ROUND_CLOSEST(QUPV3_UART_SRC_HZ, uart_freq);
	write32(&regs->geni_ser_m_clk_cfg, (div << 4) | 1);
	write32(&regs->geni_ser_s_clk_cfg, (div << 4) | 1);

	/* GPIO Configuration */
	gpio_configure(qup[idx].pin[2], qup[idx].func[2], GPIO_PULL_UP,
				GPIO_2MA, GPIO_OUTPUT);
	gpio_configure(qup[idx].pin[3], qup[idx].func[3], GPIO_PULL_UP,
				GPIO_2MA, GPIO_INPUT);

	write32(&regs->geni_tx_watermark_reg, UART_TX_WATERMARK_MARGIN);
	write32(&regs->geni_rx_watermark_reg, FIFO_DEPTH
					- UART_RX_WATERMARK_MARGIN);
	write32(&regs->geni_rx_rfr_watermark_reg,
			FIFO_DEPTH - UART_RX_RFR_WATERMARK_MARGIN);

	write32(&regs->uart_tx_word_len, UART_TX_BITS_PER_WORD);
	write32(&regs->uart_rx_word_len, UART_RX_BITS_PER_WORD);

	/* Disable TX parity calculation */
	write32(&regs->uart_tx_parity_cfg, 0x0);
	/* Ignore CTS line status for TX communication */
	write32(&regs->uart_tx_trans_cfg_reg, 0x2);
	/* Disable RX parity calculation */
	write32(&regs->uart_rx_parity_cfg, 0x0);
	/* Disable parity, framing and break check on received word */
	write32(&regs->uart_rx_trans_cfg, 0x0);
	/* Set UART TX stop bit len to one UART bit length */
	write32(&regs->uart_tx_stop_bit_len, 0x0);
	write32(&regs->uart_rx_stale_cnt, 0x16 * 10);

	write32(&regs->geni_tx_packing_cfg0, UART_TX_PACK_VECTOR0 |
						(UART_TX_PACK_VECTOR1 << 10));
	write32(&regs->geni_tx_packing_cfg1, UART_TX_PACK_VECTOR2 |
						(UART_TX_PACK_VECTOR3 << 10));
	write32(&regs->geni_rx_packing_cfg0, UART_RX_PACK_VECTOR0);
	write32(&regs->geni_rx_packing_cfg1, UART_RX_PACK_VECTOR2);

	/* Start RX */
	write32(&regs->geni_s_cmd0, START_UART_RX);
}

unsigned char uart_rx_byte(int idx)
{
	struct qup_regs *regs = qup[idx].regs;

	if (read32(&regs->geni_rx_fifo_status) & RX_FIFO_WC_MSK)
		return read32(&regs->geni_rx_fifon) & 0xFF;
	return 0;
}

void uart_tx_byte(int idx, unsigned char data)
{
	struct qup_regs *regs = qup[idx].regs;

	uart_tx_flush(idx);

	write32(&regs->uart_tx_trans_len, 1);
	/* Start TX */
	write32(&regs->geni_m_cmd0, START_UART_TX);
	write32(&regs->geni_tx_fifon, data);
}

uintptr_t uart_platform_base(int idx)
{
	return (uintptr_t)qup[idx].regs;
}

void uart_fill_lb(void *data)
{
	struct lb_serial serial = {0};

	serial.type = LB_SERIAL_TYPE_MEMORY_MAPPED;
	serial.baseaddr = (uint32_t)uart_platform_base(CONFIG_UART_FOR_CONSOLE);
	serial.baud = get_uart_baudrate();
	serial.regwidth = 4;
	serial.input_hertz = QUPV3_UART_SRC_HZ;

	lb_add_serial(&serial, data);
}