aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/ar71xx/patches-3.3/124-MIPS-ath79-rework-IP2-IP3-interrupt-handling.patch
blob: 0f30d3836f737a04c9fc05a793b2881a8629e520 (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
154
155
156
157
158
From f44c70eb5368c0742a8f401ccf39f2ba7252f5a7 Mon Sep 17 00:00:00 2001
From: Gabor Juhos <juhosg@openwrt.org>
Date: Wed, 14 Mar 2012 10:45:24 +0100
Subject: [PATCH 29/47] MIPS: ath79: rework IP2/IP3 interrupt handling

The current implementation assumes that flushing the
DDR writeback buffer is required for IP2/IP3 interrupts,
however this is not true for all SoCs.

Use SoC specific IP2/IP3 handlers instead of flushing
the buffers in the dispatcher code.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Acked-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Cc: linux-mips@linux-mips.org
Cc: mcgrof@infradead.org
Patchwork: https://patchwork.linux-mips.org/patch/3509/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
 arch/mips/ath79/irq.c |   92 ++++++++++++++++++++++++++++++++++++++-----------
 1 files changed, 72 insertions(+), 20 deletions(-)

--- a/arch/mips/ath79/irq.c
+++ b/arch/mips/ath79/irq.c
@@ -1,7 +1,7 @@
 /*
  *  Atheros AR71xx/AR724x/AR913x specific interrupt handling
  *
- *  Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
+ *  Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
  *
  *  Parts of this file are based on Atheros' 2.6.15 BSP
@@ -23,8 +23,8 @@
 #include <asm/mach-ath79/ar71xx_regs.h>
 #include "common.h"
 
-static unsigned int ath79_ip2_flush_reg;
-static unsigned int ath79_ip3_flush_reg;
+static void (*ath79_ip2_handler)(void);
+static void (*ath79_ip3_handler)(void);
 
 static void ath79_misc_irq_handler(unsigned int irq, struct irq_desc *desc)
 {
@@ -152,10 +152,8 @@ asmlinkage void plat_irq_dispatch(void)
 	if (pending & STATUSF_IP7)
 		do_IRQ(ATH79_CPU_IRQ_TIMER);
 
-	else if (pending & STATUSF_IP2) {
-		ath79_ddr_wb_flush(ath79_ip2_flush_reg);
-		do_IRQ(ATH79_CPU_IRQ_IP2);
-	}
+	else if (pending & STATUSF_IP2)
+		ath79_ip2_handler();
 
 	else if (pending & STATUSF_IP4)
 		do_IRQ(ATH79_CPU_IRQ_GE0);
@@ -163,10 +161,8 @@ asmlinkage void plat_irq_dispatch(void)
 	else if (pending & STATUSF_IP5)
 		do_IRQ(ATH79_CPU_IRQ_GE1);
 
-	else if (pending & STATUSF_IP3) {
-		ath79_ddr_wb_flush(ath79_ip3_flush_reg);
-		do_IRQ(ATH79_CPU_IRQ_USB);
-	}
+	else if (pending & STATUSF_IP3)
+		ath79_ip3_handler();
 
 	else if (pending & STATUSF_IP6)
 		do_IRQ(ATH79_CPU_IRQ_MISC);
@@ -175,22 +171,78 @@ asmlinkage void plat_irq_dispatch(void)
 		spurious_interrupt();
 }
 
+/*
+ * The IP2/IP3 lines are tied to a PCI/WMAC/USB device. Drivers for
+ * these devices typically allocate coherent DMA memory, however the
+ * DMA controller may still have some unsynchronized data in the FIFO.
+ * Issue a flush in the handlers to ensure that the driver sees
+ * the update.
+ */
+static void ar71xx_ip2_handler(void)
+{
+	ath79_ddr_wb_flush(AR71XX_DDR_REG_FLUSH_PCI);
+	do_IRQ(ATH79_CPU_IRQ_IP2);
+}
+
+static void ar724x_ip2_handler(void)
+{
+	ath79_ddr_wb_flush(AR724X_DDR_REG_FLUSH_PCIE);
+	do_IRQ(ATH79_CPU_IRQ_IP2);
+}
+
+static void ar913x_ip2_handler(void)
+{
+	ath79_ddr_wb_flush(AR913X_DDR_REG_FLUSH_WMAC);
+	do_IRQ(ATH79_CPU_IRQ_IP2);
+}
+
+static void ar933x_ip2_handler(void)
+{
+	ath79_ddr_wb_flush(AR933X_DDR_REG_FLUSH_WMAC);
+	do_IRQ(ATH79_CPU_IRQ_IP2);
+}
+
+static void ar71xx_ip3_handler(void)
+{
+	ath79_ddr_wb_flush(AR71XX_DDR_REG_FLUSH_USB);
+	do_IRQ(ATH79_CPU_IRQ_USB);
+}
+
+static void ar724x_ip3_handler(void)
+{
+	ath79_ddr_wb_flush(AR724X_DDR_REG_FLUSH_USB);
+	do_IRQ(ATH79_CPU_IRQ_USB);
+}
+
+static void ar913x_ip3_handler(void)
+{
+	ath79_ddr_wb_flush(AR913X_DDR_REG_FLUSH_USB);
+	do_IRQ(ATH79_CPU_IRQ_USB);
+}
+
+static void ar933x_ip3_handler(void)
+{
+	ath79_ddr_wb_flush(AR933X_DDR_REG_FLUSH_USB);
+	do_IRQ(ATH79_CPU_IRQ_USB);
+}
+
 void __init arch_init_irq(void)
 {
 	if (soc_is_ar71xx()) {
-		ath79_ip2_flush_reg = AR71XX_DDR_REG_FLUSH_PCI;
-		ath79_ip3_flush_reg = AR71XX_DDR_REG_FLUSH_USB;
+		ath79_ip2_handler = ar71xx_ip2_handler;
+		ath79_ip3_handler = ar71xx_ip3_handler;
 	} else if (soc_is_ar724x()) {
-		ath79_ip2_flush_reg = AR724X_DDR_REG_FLUSH_PCIE;
-		ath79_ip3_flush_reg = AR724X_DDR_REG_FLUSH_USB;
+		ath79_ip2_handler = ar724x_ip2_handler;
+		ath79_ip3_handler = ar724x_ip3_handler;
 	} else if (soc_is_ar913x()) {
-		ath79_ip2_flush_reg = AR913X_DDR_REG_FLUSH_WMAC;
-		ath79_ip3_flush_reg = AR913X_DDR_REG_FLUSH_USB;
+		ath79_ip2_handler = ar913x_ip2_handler;
+		ath79_ip3_handler = ar913x_ip3_handler;
 	} else if (soc_is_ar933x()) {
-		ath79_ip2_flush_reg = AR933X_DDR_REG_FLUSH_WMAC;
-		ath79_ip3_flush_reg = AR933X_DDR_REG_FLUSH_USB;
-	} else
+		ath79_ip2_handler = ar933x_ip2_handler;
+		ath79_ip3_handler = ar933x_ip3_handler;
+	} else {
 		BUG();
+	}
 
 	cp0_perfcount_irq = ATH79_MISC_IRQ_PERFC;
 	mips_cpu_irq_init();