xref: /openbmc/linux/drivers/ssb/driver_extif.c (revision 95e9fd10)
1 /*
2  * Sonics Silicon Backplane
3  * Broadcom EXTIF core driver
4  *
5  * Copyright 2005, Broadcom Corporation
6  * Copyright 2006, 2007, Michael Buesch <m@bues.ch>
7  * Copyright 2006, 2007, Felix Fietkau <nbd@openwrt.org>
8  * Copyright 2007, Aurelien Jarno <aurelien@aurel32.net>
9  *
10  * Licensed under the GNU/GPL. See COPYING for details.
11  */
12 
13 #include <linux/serial.h>
14 #include <linux/serial_core.h>
15 #include <linux/serial_reg.h>
16 
17 #include "ssb_private.h"
18 
19 
20 static inline u32 extif_read32(struct ssb_extif *extif, u16 offset)
21 {
22 	return ssb_read32(extif->dev, offset);
23 }
24 
25 static inline void extif_write32(struct ssb_extif *extif, u16 offset, u32 value)
26 {
27 	ssb_write32(extif->dev, offset, value);
28 }
29 
30 static inline u32 extif_write32_masked(struct ssb_extif *extif, u16 offset,
31 				       u32 mask, u32 value)
32 {
33 	value &= mask;
34 	value |= extif_read32(extif, offset) & ~mask;
35 	extif_write32(extif, offset, value);
36 
37 	return value;
38 }
39 
40 #ifdef CONFIG_SSB_SERIAL
41 static bool serial_exists(u8 *regs)
42 {
43 	u8 save_mcr, msr = 0;
44 
45 	if (regs) {
46 		save_mcr = regs[UART_MCR];
47 		regs[UART_MCR] = (UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_RTS);
48 		msr = regs[UART_MSR] & (UART_MSR_DCD | UART_MSR_RI
49 					| UART_MSR_CTS | UART_MSR_DSR);
50 		regs[UART_MCR] = save_mcr;
51 	}
52 	return (msr == (UART_MSR_DCD | UART_MSR_CTS));
53 }
54 
55 int ssb_extif_serial_init(struct ssb_extif *extif, struct ssb_serial_port *ports)
56 {
57 	u32 i, nr_ports = 0;
58 
59 	/* Disable GPIO interrupt initially */
60 	extif_write32(extif, SSB_EXTIF_GPIO_INTPOL, 0);
61 	extif_write32(extif, SSB_EXTIF_GPIO_INTMASK, 0);
62 
63 	for (i = 0; i < 2; i++) {
64 		void __iomem *uart_regs;
65 
66 		uart_regs = ioremap_nocache(SSB_EUART, 16);
67 		if (uart_regs) {
68 			uart_regs += (i * 8);
69 
70 			if (serial_exists(uart_regs) && ports) {
71 				extif_write32(extif, SSB_EXTIF_GPIO_INTMASK, 2);
72 
73 				nr_ports++;
74 				ports[i].regs = uart_regs;
75 				ports[i].irq = 2;
76 				ports[i].baud_base = 13500000;
77 				ports[i].reg_shift = 0;
78 			}
79 			iounmap(uart_regs);
80 		}
81 	}
82 	return nr_ports;
83 }
84 #endif /* CONFIG_SSB_SERIAL */
85 
86 void ssb_extif_timing_init(struct ssb_extif *extif, unsigned long ns)
87 {
88 	u32 tmp;
89 
90 	/* Initialize extif so we can get to the LEDs and external UART */
91 	extif_write32(extif, SSB_EXTIF_PROG_CFG, SSB_EXTCFG_EN);
92 
93 	/* Set timing for the flash */
94 	tmp  = DIV_ROUND_UP(10, ns) << SSB_PROG_WCNT_3_SHIFT;
95 	tmp |= DIV_ROUND_UP(40, ns) << SSB_PROG_WCNT_1_SHIFT;
96 	tmp |= DIV_ROUND_UP(120, ns);
97 	extif_write32(extif, SSB_EXTIF_PROG_WAITCNT, tmp);
98 
99 	/* Set programmable interface timing for external uart */
100 	tmp  = DIV_ROUND_UP(10, ns) << SSB_PROG_WCNT_3_SHIFT;
101 	tmp |= DIV_ROUND_UP(20, ns) << SSB_PROG_WCNT_2_SHIFT;
102 	tmp |= DIV_ROUND_UP(100, ns) << SSB_PROG_WCNT_1_SHIFT;
103 	tmp |= DIV_ROUND_UP(120, ns);
104 	extif_write32(extif, SSB_EXTIF_PROG_WAITCNT, tmp);
105 }
106 
107 void ssb_extif_get_clockcontrol(struct ssb_extif *extif,
108 				u32 *pll_type, u32 *n, u32 *m)
109 {
110 	*pll_type = SSB_PLLTYPE_1;
111 	*n = extif_read32(extif, SSB_EXTIF_CLOCK_N);
112 	*m = extif_read32(extif, SSB_EXTIF_CLOCK_SB);
113 }
114 
115 void ssb_extif_watchdog_timer_set(struct ssb_extif *extif,
116 				  u32 ticks)
117 {
118 	extif_write32(extif, SSB_EXTIF_WATCHDOG, ticks);
119 }
120 
121 u32 ssb_extif_gpio_in(struct ssb_extif *extif, u32 mask)
122 {
123 	return extif_read32(extif, SSB_EXTIF_GPIO_IN) & mask;
124 }
125 
126 u32 ssb_extif_gpio_out(struct ssb_extif *extif, u32 mask, u32 value)
127 {
128 	return extif_write32_masked(extif, SSB_EXTIF_GPIO_OUT(0),
129 				   mask, value);
130 }
131 
132 u32 ssb_extif_gpio_outen(struct ssb_extif *extif, u32 mask, u32 value)
133 {
134 	return extif_write32_masked(extif, SSB_EXTIF_GPIO_OUTEN(0),
135 				   mask, value);
136 }
137 
138 u32 ssb_extif_gpio_polarity(struct ssb_extif *extif, u32 mask, u32 value)
139 {
140 	return extif_write32_masked(extif, SSB_EXTIF_GPIO_INTPOL, mask, value);
141 }
142 
143 u32 ssb_extif_gpio_intmask(struct ssb_extif *extif, u32 mask, u32 value)
144 {
145 	return extif_write32_masked(extif, SSB_EXTIF_GPIO_INTMASK, mask, value);
146 }
147