ralink: fix rcu_sched stalls on mt7621
[openwrt/openwrt.git] / target / linux / ramips / patches-4.9 / 101-mt7621-timer.patch
1 Index: linux-4.9.37/arch/mips/kernel/smp-cmp.c
2 ===================================================================
3 --- linux-4.9.37.orig/arch/mips/kernel/smp-cmp.c
4 +++ linux-4.9.37/arch/mips/kernel/smp-cmp.c
5 @@ -43,6 +43,10 @@ static void cmp_init_secondary(void)
6 {
7 struct cpuinfo_mips *c __maybe_unused = &current_cpu_data;
8
9 + printk("%s:%s[%d]%x\n", __FILE__, __func__, __LINE__, c->core);
10 + c->core = (read_c0_ebase() & 0x3ff) >> (fls(smp_num_siblings)-1);
11 + printk("%s:%s[%d]%x\n", __FILE__, __func__, __LINE__, c->core);
12 +
13 /* Assume GIC is present */
14 change_c0_status(ST0_IM, STATUSF_IP2 | STATUSF_IP3 | STATUSF_IP4 |
15 STATUSF_IP5 | STATUSF_IP6 | STATUSF_IP7);
16 Index: linux-4.9.37/arch/mips/ralink/mt7621.c
17 ===================================================================
18 --- linux-4.9.37.orig/arch/mips/ralink/mt7621.c
19 +++ linux-4.9.37/arch/mips/ralink/mt7621.c
20 @@ -18,6 +18,7 @@
21 #include <asm/mach-ralink/ralink_regs.h>
22 #include <asm/mach-ralink/mt7621.h>
23 #include <asm/mips-boards/launch.h>
24 +#include <asm/delay.h>
25
26 #include <pinmux.h>
27
28 @@ -179,6 +180,58 @@ bool plat_cpu_core_present(int core)
29 return true;
30 }
31
32 +#define LPS_PREC 8
33 +/*
34 +* Re-calibration lpj(loop-per-jiffy).
35 +* (derived from kernel/calibrate.c)
36 +*/
37 +static int udelay_recal(void)
38 +{
39 + unsigned int i, lpj = 0;
40 + unsigned long ticks, loopbit;
41 + int lps_precision = LPS_PREC;
42 +
43 + lpj = (1<<12);
44 +
45 + while ((lpj <<= 1) != 0) {
46 + /* wait for "start of" clock tick */
47 + ticks = jiffies;
48 + while (ticks == jiffies)
49 + /* nothing */;
50 +
51 + /* Go .. */
52 + ticks = jiffies;
53 + __delay(lpj);
54 + ticks = jiffies - ticks;
55 + if (ticks)
56 + break;
57 + }
58 +
59 + /*
60 + * Do a binary approximation to get lpj set to
61 + * equal one clock (up to lps_precision bits)
62 + */
63 + lpj >>= 1;
64 + loopbit = lpj;
65 + while (lps_precision-- && (loopbit >>= 1)) {
66 + lpj |= loopbit;
67 + ticks = jiffies;
68 + while (ticks == jiffies)
69 + /* nothing */;
70 + ticks = jiffies;
71 + __delay(lpj);
72 + if (jiffies != ticks) /* longer than 1 tick */
73 + lpj &= ~loopbit;
74 + }
75 + printk(KERN_INFO "%d CPUs re-calibrate udelay(lpj = %d)\n", NR_CPUS, lpj);
76 +
77 + for(i=0; i< NR_CPUS; i++)
78 + cpu_data[i].udelay_val = lpj;
79 +
80 + return 0;
81 +}
82 +device_initcall(udelay_recal);
83 +
84 void prom_soc_init(struct ralink_soc_info *soc_info)
85 {
86 void __iomem *sysc = (void __iomem *) KSEG1ADDR(MT7621_SYSC_BASE);
87 Index: linux-4.9.37/arch/mips/ralink/Kconfig
88 ===================================================================
89 --- linux-4.9.37.orig/arch/mips/ralink/Kconfig
90 +++ linux-4.9.37/arch/mips/ralink/Kconfig
91 @@ -56,6 +56,7 @@ choice
92 select COMMON_CLK
93 select CLKSRC_MIPS_GIC
94 select HW_HAS_PCI
95 + select GENERIC_CLOCKEVENTS_BROADCAST
96 endchoice
97
98 choice
99 Index: linux-4.9.37/arch/mips/ralink/timer-gic.c
100 ===================================================================
101 --- linux-4.9.37.orig/arch/mips/ralink/timer-gic.c
102 +++ linux-4.9.37/arch/mips/ralink/timer-gic.c
103 @@ -12,6 +12,7 @@
104 #include <linux/of.h>
105 #include <linux/clk-provider.h>
106 #include <linux/clocksource.h>
107 +#include <asm/time.h>
108
109 #include "common.h"
110
111 @@ -19,6 +20,8 @@ void __init plat_time_init(void)
112 {
113 ralink_of_remap();
114
115 + mips_hpt_frequency = 880000000 / 2;
116 +
117 of_clk_init(NULL);
118 clocksource_probe();
119 }