summaryrefslogtreecommitdiff
path: root/target/linux/ar71xx/patches-3.3/113-MIPS-ath79-add-PCI-IRQ-handling-code-for-AR724X-SoCs.patch
blob: 6da2df4993482c86f3e812d0abac08a9eabc1431 (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
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
From a4fbc2dec67a5d760e25e3c3a6c392191a5405c6 Mon Sep 17 00:00:00 2001
From: Gabor Juhos <juhosg@openwrt.org>
Date: Tue, 22 Nov 2011 14:11:19 +0100
Subject: [PATCH 13/35] MIPS: ath79: add PCI IRQ handling code for AR724X SoCs

The PCI Host Controller of the AR724x SoC has a
built-in IRQ controller. The current code does
not supports that, so the IRQ lines wired to this
controller are not usable. This leads to failed
'request_irq' calls:

  ath9k 0000:00:00.0: request_irq failed
  ath9k: probe of 0000:00:00.0 failed with error -89

This patch adds support for the IRQ controller
in order to make PCI IRQs work.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

v2: - move the interrupt controller related defines from
      the workaround patch
---
 arch/mips/ath79/pci.c                  |    3 +-
 arch/mips/include/asm/mach-ath79/pci.h |    4 +-
 arch/mips/pci/pci-ar724x.c             |  118 +++++++++++++++++++++++++++++++-
 3 files changed, 120 insertions(+), 5 deletions(-)

--- a/arch/mips/ath79/pci.c
+++ b/arch/mips/ath79/pci.c
@@ -10,6 +10,7 @@
 
 #include <linux/pci.h>
 #include <asm/mach-ath79/ath79.h>
+#include <asm/mach-ath79/irq.h>
 #include <asm/mach-ath79/pci.h>
 #include "pci.h"
 
@@ -50,7 +51,7 @@ int pcibios_plat_dev_init(struct pci_dev
 int __init ath79_register_pci(void)
 {
 	if (soc_is_ar724x())
-		return ar724x_pcibios_init();
+		return ar724x_pcibios_init(ATH79_CPU_IRQ_IP2);
 
 	return -ENODEV;
 }
--- a/arch/mips/include/asm/mach-ath79/pci.h
+++ b/arch/mips/include/asm/mach-ath79/pci.h
@@ -12,9 +12,9 @@
 #define __ASM_MACH_ATH79_PCI_H
 
 #if defined(CONFIG_PCI) && defined(CONFIG_SOC_AR724X)
-int ar724x_pcibios_init(void);
+int ar724x_pcibios_init(int irq);
 #else
-static inline int ar724x_pcibios_init(void) { return 0 };
+static inline int ar724x_pcibios_init(int irq) { return 0 };
 #endif
 
 #endif /* __ASM_MACH_ATH79_PCI_H */
--- a/arch/mips/pci/pci-ar724x.c
+++ b/arch/mips/pci/pci-ar724x.c
@@ -8,19 +8,32 @@
  *  by the Free Software Foundation.
  */
 
+#include <linux/irq.h>
 #include <linux/pci.h>
 #include <asm/mach-ath79/ath79.h>
+#include <asm/mach-ath79/ar71xx_regs.h>
 #include <asm/mach-ath79/pci.h>
 
 #define AR724X_PCI_CFG_BASE	0x14000000
 #define AR724X_PCI_CFG_SIZE	0x1000
+#define AR724X_PCI_CTRL_BASE	(AR71XX_APB_BASE + 0x000f0000)
+#define AR724X_PCI_CTRL_SIZE	0x100
+
 #define AR724X_PCI_MEM_BASE	0x10000000
 #define AR724X_PCI_MEM_SIZE	0x08000000
 
+#define AR724X_PCI_REG_INT_STATUS	0x4c
+#define AR724X_PCI_REG_INT_MASK		0x50
+
+#define AR724X_PCI_INT_DEV0		BIT(14)
+
+#define AR724X_PCI_IRQ_COUNT		1
+
 #define AR7240_BAR0_WAR_VALUE	0xffff
 
 static DEFINE_SPINLOCK(ar724x_pci_lock);
 static void __iomem *ar724x_pci_devcfg_base;
+static void __iomem *ar724x_pci_ctrl_base;
 
 static u32 ar724x_pci_bar0_value;
 static bool ar724x_pci_bar0_is_cached;
@@ -164,14 +177,115 @@ static struct pci_controller ar724x_pci_
 	.mem_resource	= &ar724x_mem_resource,
 };
 
-int __init ar724x_pcibios_init(void)
+static void ar724x_pci_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	void __iomem *base;
+	u32 pending;
+
+	base = ar724x_pci_ctrl_base;
+
+	pending = __raw_readl(base + AR724X_PCI_REG_INT_STATUS) &
+		  __raw_readl(base + AR724X_PCI_REG_INT_MASK);
+
+	if (pending & AR724X_PCI_INT_DEV0)
+		generic_handle_irq(ATH79_PCI_IRQ(0));
+
+	else
+		spurious_interrupt();
+}
+
+static void ar724x_pci_irq_unmask(struct irq_data *d)
+{
+	void __iomem *base;
+	u32 t;
+
+	base = ar724x_pci_ctrl_base;
+
+	switch (d->irq) {
+	case ATH79_PCI_IRQ(0):
+		t = __raw_readl(base + AR724X_PCI_REG_INT_MASK);
+		__raw_writel(t | AR724X_PCI_INT_DEV0,
+			     base + AR724X_PCI_REG_INT_MASK);
+		/* flush write */
+		__raw_readl(base + AR724X_PCI_REG_INT_MASK);
+	}
+}
+
+static void ar724x_pci_irq_mask(struct irq_data *d)
+{
+	void __iomem *base;
+	u32 t;
+
+	base = ar724x_pci_ctrl_base;
+
+	switch (d->irq) {
+	case ATH79_PCI_IRQ(0):
+		t = __raw_readl(base + AR724X_PCI_REG_INT_MASK);
+		__raw_writel(t & ~AR724X_PCI_INT_DEV0,
+			     base + AR724X_PCI_REG_INT_MASK);
+
+		/* flush write */
+		__raw_readl(base + AR724X_PCI_REG_INT_MASK);
+
+		t = __raw_readl(base + AR724X_PCI_REG_INT_STATUS);
+		__raw_writel(t | AR724X_PCI_INT_DEV0,
+			     base + AR724X_PCI_REG_INT_STATUS);
+
+		/* flush write */
+		__raw_readl(base + AR724X_PCI_REG_INT_STATUS);
+	}
+}
+
+static struct irq_chip ar724x_pci_irq_chip = {
+	.name		= "AR724X PCI ",
+	.irq_mask	= ar724x_pci_irq_mask,
+	.irq_unmask	= ar724x_pci_irq_unmask,
+	.irq_mask_ack	= ar724x_pci_irq_mask,
+};
+
+static void __init ar724x_pci_irq_init(int irq)
+{
+	void __iomem *base;
+	int i;
+
+	base = ar724x_pci_ctrl_base;
+
+	__raw_writel(0, base + AR724X_PCI_REG_INT_MASK);
+	__raw_writel(0, base + AR724X_PCI_REG_INT_STATUS);
+
+	BUILD_BUG_ON(ATH79_PCI_IRQ_COUNT < AR724X_PCI_IRQ_COUNT);
+
+	for (i = ATH79_PCI_IRQ_BASE;
+	     i < ATH79_PCI_IRQ_BASE + AR724X_PCI_IRQ_COUNT; i++)
+		irq_set_chip_and_handler(i, &ar724x_pci_irq_chip,
+					 handle_level_irq);
+
+	irq_set_chained_handler(irq, ar724x_pci_irq_handler);
+}
+
+int __init ar724x_pcibios_init(int irq)
 {
+	int ret;
+
+	ret = -ENOMEM;
+
 	ar724x_pci_devcfg_base = ioremap(AR724X_PCI_CFG_BASE,
 					 AR724X_PCI_CFG_SIZE);
 	if (ar724x_pci_devcfg_base == NULL)
-		return -ENOMEM;
+		goto err;
 
+	ar724x_pci_ctrl_base = ioremap(AR724X_PCI_CTRL_BASE,
+				       AR724X_PCI_CTRL_SIZE);
+	if (ar724x_pci_ctrl_base == NULL)
+		goto err_unmap_devcfg;
+
+	ar724x_pci_irq_init(irq);
 	register_pci_controller(&ar724x_pci_controller);
 
 	return PCIBIOS_SUCCESSFUL;
+
+err_unmap_devcfg:
+	iounmap(ar724x_pci_devcfg_base);
+err:
+	return ret;
 }