1 /*
2  * Renesas Technology Europe SDK7786 Support.
3  *
4  * Copyright (C) 2010  Matt Fleming
5  * Copyright (C) 2010  Paul Mundt
6  *
7  * This file is subject to the terms and conditions of the GNU General Public
8  * License.  See the file "COPYING" in the main directory of this archive
9  * for more details.
10  */
11 #include <linux/init.h>
12 #include <linux/platform_device.h>
13 #include <linux/io.h>
14 #include <linux/smsc911x.h>
15 #include <linux/i2c.h>
16 #include <linux/irq.h>
17 #include <linux/clk.h>
18 #include <linux/clkdev.h>
19 #include <mach/fpga.h>
20 #include <mach/irq.h>
21 #include <asm/machvec.h>
22 #include <asm/heartbeat.h>
23 #include <asm/sizes.h>
24 #include <asm/clock.h>
25 #include <asm/reboot.h>
26 #include <asm/smp-ops.h>
27 
28 static struct resource heartbeat_resource = {
29 	.start		= 0x07fff8b0,
30 	.end		= 0x07fff8b0 + sizeof(u16) - 1,
31 	.flags		= IORESOURCE_MEM | IORESOURCE_MEM_16BIT,
32 };
33 
34 static struct platform_device heartbeat_device = {
35 	.name		= "heartbeat",
36 	.id		= -1,
37 	.num_resources	= 1,
38 	.resource	= &heartbeat_resource,
39 };
40 
41 static struct resource smsc911x_resources[] = {
42 	[0] = {
43 		.name		= "smsc911x-memory",
44 		.start		= 0x07ffff00,
45 		.end		= 0x07ffff00 + SZ_256 - 1,
46 		.flags		= IORESOURCE_MEM,
47 	},
48 	[1] = {
49 		.name		= "smsc911x-irq",
50 		.start		= evt2irq(0x2c0),
51 		.end		= evt2irq(0x2c0),
52 		.flags		= IORESOURCE_IRQ,
53 	},
54 };
55 
56 static struct smsc911x_platform_config smsc911x_config = {
57 	.irq_polarity	= SMSC911X_IRQ_POLARITY_ACTIVE_LOW,
58 	.irq_type	= SMSC911X_IRQ_TYPE_OPEN_DRAIN,
59 	.flags		= SMSC911X_USE_32BIT,
60 	.phy_interface	= PHY_INTERFACE_MODE_MII,
61 };
62 
63 static struct platform_device smsc911x_device = {
64 	.name		= "smsc911x",
65 	.id		= -1,
66 	.num_resources	= ARRAY_SIZE(smsc911x_resources),
67 	.resource	= smsc911x_resources,
68 	.dev = {
69 		.platform_data = &smsc911x_config,
70 	},
71 };
72 
73 static struct resource smbus_fpga_resource = {
74 	.start		= 0x07fff9e0,
75 	.end		= 0x07fff9e0 + SZ_32 - 1,
76 	.flags		= IORESOURCE_MEM,
77 };
78 
79 static struct platform_device smbus_fpga_device = {
80 	.name		= "i2c-sdk7786",
81 	.id		= 0,
82 	.num_resources	= 1,
83 	.resource	= &smbus_fpga_resource,
84 };
85 
86 static struct resource smbus_pcie_resource = {
87 	.start		= 0x07fffc30,
88 	.end		= 0x07fffc30 + SZ_32 - 1,
89 	.flags		= IORESOURCE_MEM,
90 };
91 
92 static struct platform_device smbus_pcie_device = {
93 	.name		= "i2c-sdk7786",
94 	.id		= 1,
95 	.num_resources	= 1,
96 	.resource	= &smbus_pcie_resource,
97 };
98 
99 static struct i2c_board_info __initdata sdk7786_i2c_devices[] = {
100 	{
101 		I2C_BOARD_INFO("max6900", 0x68),
102 	},
103 };
104 
105 static struct platform_device *sh7786_devices[] __initdata = {
106 	&heartbeat_device,
107 	&smsc911x_device,
108 	&smbus_fpga_device,
109 	&smbus_pcie_device,
110 };
111 
112 static int sdk7786_i2c_setup(void)
113 {
114 	unsigned int tmp;
115 
116 	/*
117 	 * Hand over I2C control to the FPGA.
118 	 */
119 	tmp = fpga_read_reg(SBCR);
120 	tmp &= ~SCBR_I2CCEN;
121 	tmp |= SCBR_I2CMEN;
122 	fpga_write_reg(tmp, SBCR);
123 
124 	return i2c_register_board_info(0, sdk7786_i2c_devices,
125 				       ARRAY_SIZE(sdk7786_i2c_devices));
126 }
127 
128 static int __init sdk7786_devices_setup(void)
129 {
130 	int ret;
131 
132 	ret = platform_add_devices(sh7786_devices, ARRAY_SIZE(sh7786_devices));
133 	if (unlikely(ret != 0))
134 		return ret;
135 
136 	return sdk7786_i2c_setup();
137 }
138 device_initcall(sdk7786_devices_setup);
139 
140 static int sdk7786_mode_pins(void)
141 {
142 	return fpga_read_reg(MODSWR);
143 }
144 
145 /*
146  * FPGA-driven PCIe clocks
147  *
148  * Historically these include the oscillator, clock B (slots 2/3/4) and
149  * clock A (slot 1 and the CPU clock). Newer revs of the PCB shove
150  * everything under a single PCIe clocks enable bit that happens to map
151  * to the same bit position as the oscillator bit for earlier FPGA
152  * versions.
153  *
154  * Given that the legacy clocks have the side-effect of shutting the CPU
155  * off through the FPGA along with the PCI slots, we simply leave them in
156  * their initial state and don't bother registering them with the clock
157  * framework.
158  */
159 static int sdk7786_pcie_clk_enable(struct clk *clk)
160 {
161 	fpga_write_reg(fpga_read_reg(PCIECR) | PCIECR_CLKEN, PCIECR);
162 	return 0;
163 }
164 
165 static void sdk7786_pcie_clk_disable(struct clk *clk)
166 {
167 	fpga_write_reg(fpga_read_reg(PCIECR) & ~PCIECR_CLKEN, PCIECR);
168 }
169 
170 static struct sh_clk_ops sdk7786_pcie_clk_ops = {
171 	.enable		= sdk7786_pcie_clk_enable,
172 	.disable	= sdk7786_pcie_clk_disable,
173 };
174 
175 static struct clk sdk7786_pcie_clk = {
176 	.ops		= &sdk7786_pcie_clk_ops,
177 };
178 
179 static struct clk_lookup sdk7786_pcie_cl = {
180 	.con_id		= "pcie_plat_clk",
181 	.clk		= &sdk7786_pcie_clk,
182 };
183 
184 static int sdk7786_clk_init(void)
185 {
186 	struct clk *clk;
187 	int ret;
188 
189 	/*
190 	 * Only handle the EXTAL case, anyone interfacing a crystal
191 	 * resonator will need to provide their own input clock.
192 	 */
193 	if (test_mode_pin(MODE_PIN9))
194 		return -EINVAL;
195 
196 	clk = clk_get(NULL, "extal");
197 	if (IS_ERR(clk))
198 		return PTR_ERR(clk);
199 	ret = clk_set_rate(clk, 33333333);
200 	clk_put(clk);
201 
202 	/*
203 	 * Setup the FPGA clocks.
204 	 */
205 	ret = clk_register(&sdk7786_pcie_clk);
206 	if (unlikely(ret)) {
207 		pr_err("FPGA clock registration failed\n");
208 		return ret;
209 	}
210 
211 	clkdev_add(&sdk7786_pcie_cl);
212 
213 	return 0;
214 }
215 
216 static void sdk7786_restart(char *cmd)
217 {
218 	fpga_write_reg(0xa5a5, SRSTR);
219 }
220 
221 static void sdk7786_power_off(void)
222 {
223 	fpga_write_reg(fpga_read_reg(PWRCR) | PWRCR_PDWNREQ, PWRCR);
224 
225 	/*
226 	 * It can take up to 20us for the R8C to do its job, back off and
227 	 * wait a bit until we've been shut off. Even though newer FPGA
228 	 * versions don't set the ACK bit, the latency issue remains.
229 	 */
230 	while ((fpga_read_reg(PWRCR) & PWRCR_PDWNACK) == 0)
231 		cpu_sleep();
232 }
233 
234 /* Initialize the board */
235 static void __init sdk7786_setup(char **cmdline_p)
236 {
237 	pr_info("Renesas Technology Europe SDK7786 support:\n");
238 
239 	sdk7786_fpga_init();
240 	sdk7786_nmi_init();
241 
242 	pr_info("\tPCB revision:\t%d\n", fpga_read_reg(PCBRR) & 0xf);
243 
244 	machine_ops.restart = sdk7786_restart;
245 	pm_power_off = sdk7786_power_off;
246 
247 	register_smp_ops(&shx3_smp_ops);
248 }
249 
250 /*
251  * The Machine Vector
252  */
253 static struct sh_machine_vector mv_sdk7786 __initmv = {
254 	.mv_name		= "SDK7786",
255 	.mv_setup		= sdk7786_setup,
256 	.mv_mode_pins		= sdk7786_mode_pins,
257 	.mv_clk_init		= sdk7786_clk_init,
258 	.mv_init_irq		= sdk7786_init_irq,
259 };
260