2 * Copyright (C) 2016 Imagination Technologies
3 * Author: Paul Burton <paul.burton@imgtec.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
11 #define pr_fmt(fmt) "sead3: " fmt
13 #include <linux/errno.h>
14 #include <linux/libfdt.h>
15 #include <linux/printk.h>
17 #include <asm/fw/fw.h>
19 #include <asm/machine.h>
21 #define SEAD_CONFIG CKSEG1ADDR(0x1b100110)
22 #define SEAD_CONFIG_GIC_PRESENT BIT(1)
24 #define MIPS_REVISION CKSEG1ADDR(0x1fc00010)
25 #define MIPS_REVISION_MACHINE (0xf << 4)
26 #define MIPS_REVISION_MACHINE_SEAD3 (0x4 << 4)
28 static __init bool sead3_detect(void)
32 rev = __raw_readl((void *)MIPS_REVISION);
33 return (rev & MIPS_REVISION_MACHINE) == MIPS_REVISION_MACHINE_SEAD3;
36 static __init int append_cmdline(void *fdt)
40 /* find or add chosen node */
41 chosen_off = fdt_path_offset(fdt, "/chosen");
42 if (chosen_off == -FDT_ERR_NOTFOUND)
43 chosen_off = fdt_path_offset(fdt, "/chosen@0");
44 if (chosen_off == -FDT_ERR_NOTFOUND)
45 chosen_off = fdt_add_subnode(fdt, 0, "chosen");
47 pr_err("Unable to find or add DT chosen node: %d\n",
52 err = fdt_setprop_string(fdt, chosen_off, "bootargs", fw_getcmdline());
54 pr_err("Unable to set bootargs property: %d\n", err);
61 static __init int append_memory(void *fdt)
63 unsigned long phys_memsize, memsize;
68 /* find memory size from the bootloader environment */
69 var = fw_getenv("memsize");
71 err = kstrtoul(var, 0, &phys_memsize);
73 pr_err("Failed to read memsize env variable '%s'\n",
78 pr_warn("The bootloader didn't provide memsize: defaulting to 32MB\n");
79 phys_memsize = 32 << 20;
82 /* default to using all available RAM */
83 memsize = phys_memsize;
85 /* allow the user to override the usable memory */
86 var = strstr(arcs_cmdline, "memsize=");
88 memsize = memparse(var + strlen("memsize="), NULL);
90 /* if the user says there's more RAM than we thought, believe them */
91 phys_memsize = max_t(unsigned long, phys_memsize, memsize);
93 /* find or add a memory node */
94 mem_off = fdt_path_offset(fdt, "/memory");
95 if (mem_off == -FDT_ERR_NOTFOUND)
96 mem_off = fdt_add_subnode(fdt, 0, "memory");
98 pr_err("Unable to find or add memory DT node: %d\n", mem_off);
102 err = fdt_setprop_string(fdt, mem_off, "device_type", "memory");
104 pr_err("Unable to set memory node device_type: %d\n", err);
109 mem_array[1] = cpu_to_be32(phys_memsize);
110 err = fdt_setprop(fdt, mem_off, "reg", mem_array, sizeof(mem_array));
112 pr_err("Unable to set memory regs property: %d\n", err);
117 mem_array[1] = cpu_to_be32(memsize);
118 err = fdt_setprop(fdt, mem_off, "linux,usable-memory",
119 mem_array, sizeof(mem_array));
121 pr_err("Unable to set linux,usable-memory property: %d\n", err);
128 static __init int remove_gic(void *fdt)
130 const unsigned int cpu_ehci_int = 2;
131 const unsigned int cpu_uart_int = 4;
132 const unsigned int cpu_eth_int = 6;
133 int gic_off, cpu_off, uart_off, eth_off, ehci_off, err;
134 uint32_t cfg, cpu_phandle;
136 /* leave the GIC node intact if a GIC is present */
137 cfg = __raw_readl((uint32_t *)SEAD_CONFIG);
138 if (cfg & SEAD_CONFIG_GIC_PRESENT)
141 gic_off = fdt_node_offset_by_compatible(fdt, -1, "mti,gic");
143 pr_err("unable to find DT GIC node: %d\n", gic_off);
147 err = fdt_nop_node(fdt, gic_off);
149 pr_err("unable to nop GIC node\n");
153 cpu_off = fdt_node_offset_by_compatible(fdt, -1,
154 "mti,cpu-interrupt-controller");
156 pr_err("unable to find CPU intc node: %d\n", cpu_off);
160 cpu_phandle = fdt_get_phandle(fdt, cpu_off);
162 pr_err("unable to get CPU intc phandle\n");
166 err = fdt_setprop_u32(fdt, 0, "interrupt-parent", cpu_phandle);
168 pr_err("unable to set root interrupt-parent: %d\n", err);
172 uart_off = fdt_node_offset_by_compatible(fdt, -1, "ns16550a");
173 while (uart_off >= 0) {
174 err = fdt_setprop_u32(fdt, uart_off, "interrupts",
177 pr_err("unable to set UART interrupts property: %d\n",
182 uart_off = fdt_node_offset_by_compatible(fdt, uart_off,
185 if (uart_off != -FDT_ERR_NOTFOUND) {
186 pr_err("error searching for UART DT node: %d\n", uart_off);
190 eth_off = fdt_node_offset_by_compatible(fdt, -1, "smsc,lan9115");
192 pr_err("unable to find ethernet DT node: %d\n", eth_off);
196 err = fdt_setprop_u32(fdt, eth_off, "interrupts", cpu_eth_int);
198 pr_err("unable to set ethernet interrupts property: %d\n", err);
202 ehci_off = fdt_node_offset_by_compatible(fdt, -1, "generic-ehci");
204 pr_err("unable to find EHCI DT node: %d\n", ehci_off);
208 err = fdt_setprop_u32(fdt, ehci_off, "interrupts", cpu_ehci_int);
210 pr_err("unable to set EHCI interrupts property: %d\n", err);
217 static __init int serial_config(void *fdt)
219 const char *yamontty, *mode_var;
220 char mode_var_name[9], path[18], parity;
221 unsigned int uart, baud, stop_bits;
225 yamontty = fw_getenv("yamontty");
226 if (!yamontty || !strcmp(yamontty, "tty0")) {
228 } else if (!strcmp(yamontty, "tty1")) {
231 pr_warn("yamontty environment variable '%s' invalid\n",
236 baud = stop_bits = 0;
240 snprintf(mode_var_name, sizeof(mode_var_name), "modetty%u", uart);
241 mode_var = fw_getenv(mode_var_name);
243 while (mode_var[0] >= '0' && mode_var[0] <= '9') {
245 baud += mode_var[0] - '0';
248 if (mode_var[0] == ',')
251 parity = mode_var[0];
252 if (mode_var[0] == ',')
255 stop_bits = mode_var[0] - '0';
256 if (mode_var[0] == ',')
258 if (!strcmp(mode_var, "hw"))
265 if (parity != 'e' && parity != 'n' && parity != 'o')
268 if (stop_bits != 7 && stop_bits != 8)
271 WARN_ON(snprintf(path, sizeof(path), "uart%u:%u%c%u%s",
272 uart, baud, parity, stop_bits,
273 hw_flow ? "r" : "") >= sizeof(path));
275 /* find or add chosen node */
276 chosen_off = fdt_path_offset(fdt, "/chosen");
277 if (chosen_off == -FDT_ERR_NOTFOUND)
278 chosen_off = fdt_path_offset(fdt, "/chosen@0");
279 if (chosen_off == -FDT_ERR_NOTFOUND)
280 chosen_off = fdt_add_subnode(fdt, 0, "chosen");
281 if (chosen_off < 0) {
282 pr_err("Unable to find or add DT chosen node: %d\n",
287 err = fdt_setprop_string(fdt, chosen_off, "stdout-path", path);
289 pr_err("Unable to set stdout-path property: %d\n", err);
296 static __init const void *sead3_fixup_fdt(const void *fdt,
297 const void *match_data)
299 static unsigned char fdt_buf[16 << 10] __initdata;
302 if (fdt_check_header(fdt))
305 /* if this isn't SEAD3, something went wrong */
306 BUG_ON(fdt_node_check_compatible(fdt, 0, "mti,sead-3"));
310 err = fdt_open_into(fdt, fdt_buf, sizeof(fdt_buf));
312 panic("Unable to open FDT: %d", err);
314 err = append_cmdline(fdt_buf);
316 panic("Unable to patch FDT: %d", err);
318 err = append_memory(fdt_buf);
320 panic("Unable to patch FDT: %d", err);
322 err = remove_gic(fdt_buf);
324 panic("Unable to patch FDT: %d", err);
326 err = serial_config(fdt_buf);
328 panic("Unable to patch FDT: %d", err);
330 err = fdt_pack(fdt_buf);
332 panic("Unable to pack FDT: %d\n", err);
337 static __init unsigned int sead3_measure_hpt_freq(void)
339 void __iomem *status_reg = (void __iomem *)0xbf000410;
340 unsigned int freq, orig, tick = 0;
343 local_irq_save(flags);
345 orig = readl(status_reg) & 0x2; /* get original sample */
346 /* wait for transition */
347 while ((readl(status_reg) & 0x2) == orig)
349 orig = orig ^ 0x2; /* flip the bit */
353 /* wait 1 second (the sampling clock transitions every 10ms) */
355 /* wait for transition */
356 while ((readl(status_reg) & 0x2) == orig)
358 orig = orig ^ 0x2; /* flip the bit */
362 freq = read_c0_count();
364 local_irq_restore(flags);
369 extern char __dtb_sead3_begin[];
371 MIPS_MACHINE(sead3) = {
372 .fdt = __dtb_sead3_begin,
373 .detect = sead3_detect,
374 .fixup_fdt = sead3_fixup_fdt,
375 .measure_hpt_freq = sead3_measure_hpt_freq,