aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/bcm27xx/patches-5.4/950-0440-x86-PCI-sta2x11-use-default-DMA-address-translation.patch
blob: 51fd4be35e1c834b5e00a3de8adeb0ef2b3881c8 (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
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
From 97a48106d1698038720495fdd49c491b283bf110 Mon Sep 17 00:00:00 2001
From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Date: Thu, 7 Nov 2019 16:06:45 +0100
Subject: [PATCH] x86/PCI: sta2x11: use default DMA address translation

commit e380a0394c36a3a878c858418d5dd7f5f195b6fc upstream.

The devices found behind this PCIe chip have unusual DMA mapping
constraints as there is an AMBA interconnect placed in between them and
the different PCI endpoints. The offset between physical memory
addresses and AMBA's view is provided by reading a PCI config register,
which is saved and used whenever DMA mapping is needed.

It turns out that this DMA setup can be represented by properly setting
'dma_pfn_offset', 'dma_bus_mask' and 'dma_mask' during the PCI device
enable fixup. And ultimately allows us to get rid of this device's
custom DMA functions.

Aside from the code deletion and DMA setup, sta2x11_pdev_to_mapping() is
moved to avoid warnings whenever CONFIG_PM is not enabled.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/x86/Kconfig                  |   1 -
 arch/x86/include/asm/device.h     |   3 -
 arch/x86/include/asm/dma-direct.h |   9 --
 arch/x86/pci/sta2x11-fixup.c      | 135 ++++++------------------------
 4 files changed, 26 insertions(+), 122 deletions(-)
 delete mode 100644 arch/x86/include/asm/dma-direct.h

--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -708,7 +708,6 @@ config X86_SUPPORTS_MEMORY_FAILURE
 config STA2X11
 	bool "STA2X11 Companion Chip Support"
 	depends on X86_32_NON_STANDARD && PCI
-	select ARCH_HAS_PHYS_TO_DMA
 	select SWIOTLB
 	select MFD_STA2X11
 	select GPIOLIB
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -6,9 +6,6 @@ struct dev_archdata {
 #if defined(CONFIG_INTEL_IOMMU) || defined(CONFIG_AMD_IOMMU)
 	void *iommu; /* hook for IOMMU specific extension */
 #endif
-#ifdef CONFIG_STA2X11
-	bool is_sta2x11;
-#endif
 };
 
 #if defined(CONFIG_X86_DEV_DMA_OPS) && defined(CONFIG_PCI_DOMAINS)
--- a/arch/x86/include/asm/dma-direct.h
+++ /dev/null
@@ -1,9 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef ASM_X86_DMA_DIRECT_H
-#define ASM_X86_DMA_DIRECT_H 1
-
-bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
-dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr);
-phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr);
-
-#endif /* ASM_X86_DMA_DIRECT_H */
--- a/arch/x86/pci/sta2x11-fixup.c
+++ b/arch/x86/pci/sta2x11-fixup.c
@@ -30,7 +30,6 @@ struct sta2x11_ahb_regs { /* saved durin
 };
 
 struct sta2x11_mapping {
-	u32 amba_base;
 	int is_suspended;
 	struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS];
 };
@@ -92,18 +91,6 @@ static int sta2x11_pdev_to_ep(struct pci
 	return pdev->bus->number - instance->bus0;
 }
 
-static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev)
-{
-	struct sta2x11_instance *instance;
-	int ep;
-
-	instance = sta2x11_pdev_to_instance(pdev);
-	if (!instance)
-		return NULL;
-	ep = sta2x11_pdev_to_ep(pdev);
-	return instance->map + ep;
-}
-
 /* This is exported, as some devices need to access the MFD registers */
 struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev)
 {
@@ -111,39 +98,6 @@ struct sta2x11_instance *sta2x11_get_ins
 }
 EXPORT_SYMBOL(sta2x11_get_instance);
 
-
-/**
- * p2a - Translate physical address to STA2x11 AMBA address,
- *       used for DMA transfers to STA2x11
- * @p: Physical address
- * @pdev: PCI device (must be hosted within the connext)
- */
-static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev)
-{
-	struct sta2x11_mapping *map;
-	dma_addr_t a;
-
-	map = sta2x11_pdev_to_mapping(pdev);
-	a = p + map->amba_base;
-	return a;
-}
-
-/**
- * a2p - Translate STA2x11 AMBA address to physical address
- *       used for DMA transfers from STA2x11
- * @a: STA2x11 AMBA address
- * @pdev: PCI device (must be hosted within the connext)
- */
-static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev)
-{
-	struct sta2x11_mapping *map;
-	dma_addr_t p;
-
-	map = sta2x11_pdev_to_mapping(pdev);
-	p = a - map->amba_base;
-	return p;
-}
-
 /* At setup time, we use our own ops if the device is a ConneXt one */
 static void sta2x11_setup_pdev(struct pci_dev *pdev)
 {
@@ -151,9 +105,6 @@ static void sta2x11_setup_pdev(struct pc
 
 	if (!instance) /* either a sta2x11 bridge or another ST device */
 		return;
-	pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
-	pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
-	pdev->dev.archdata.is_sta2x11 = true;
 
 	/* We must enable all devices as master, for audio DMA to work */
 	pci_set_master(pdev);
@@ -161,61 +112,6 @@ static void sta2x11_setup_pdev(struct pc
 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev);
 
 /*
- * The following three functions are exported (used in swiotlb: FIXME)
- */
-/**
- * dma_capable - Check if device can manage DMA transfers (FIXME: kill it)
- * @dev: device for a PCI device
- * @addr: DMA address
- * @size: DMA size
- */
-bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
-{
-	struct sta2x11_mapping *map;
-
-	if (!dev->archdata.is_sta2x11) {
-		if (!dev->dma_mask)
-			return false;
-		return addr + size - 1 <= *dev->dma_mask;
-	}
-
-	map = sta2x11_pdev_to_mapping(to_pci_dev(dev));
-
-	if (!map || (addr < map->amba_base))
-		return false;
-	if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) {
-		return false;
-	}
-
-	return true;
-}
-
-/**
- * __phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
- * @dev: device for a PCI device
- * @paddr: Physical address
- */
-dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
-{
-	if (!dev->archdata.is_sta2x11)
-		return paddr;
-	return p2a(paddr, to_pci_dev(dev));
-}
-
-/**
- * dma_to_phys - Return the physical address used for this STA2x11 DMA address
- * @dev: device for a PCI device
- * @daddr: STA2x11 AMBA DMA address
- */
-phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr)
-{
-	if (!dev->archdata.is_sta2x11)
-		return daddr;
-	return a2p(daddr, to_pci_dev(dev));
-}
-
-
-/*
  * At boot we must set up the mappings for the pcie-to-amba bridge.
  * It involves device access, and the same happens at suspend/resume time
  */
@@ -234,12 +130,22 @@ phys_addr_t __dma_to_phys(struct device
 /* At probe time, enable mapping for each endpoint, using the pdev */
 static void sta2x11_map_ep(struct pci_dev *pdev)
 {
-	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
+	struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev);
+	struct device *dev = &pdev->dev;
+	u32 amba_base, max_amba_addr;
 	int i;
 
-	if (!map)
+	if (!instance)
 		return;
-	pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base);
+
+	pci_read_config_dword(pdev, AHB_BASE(0), &amba_base);
+	max_amba_addr = amba_base + STA2X11_AMBA_SIZE - 1;
+
+	dev->dma_pfn_offset = PFN_DOWN(-amba_base);
+
+	dev->bus_dma_mask = max_amba_addr;
+	pci_set_consistent_dma_mask(pdev, max_amba_addr);
+	pci_set_dma_mask(pdev, max_amba_addr);
 
 	/* Configure AHB mapping */
 	pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0);
@@ -253,13 +159,24 @@ static void sta2x11_map_ep(struct pci_de
 
 	dev_info(&pdev->dev,
 		 "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n",
-		 sta2x11_pdev_to_ep(pdev),  map->amba_base,
-		 map->amba_base + STA2X11_AMBA_SIZE - 1);
+		 sta2x11_pdev_to_ep(pdev), amba_base, max_amba_addr);
 }
 DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep);
 
 #ifdef CONFIG_PM /* Some register values must be saved and restored */
 
+static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev)
+{
+	struct sta2x11_instance *instance;
+	int ep;
+
+	instance = sta2x11_pdev_to_instance(pdev);
+	if (!instance)
+		return NULL;
+	ep = sta2x11_pdev_to_ep(pdev);
+	return instance->map + ep;
+}
+
 static void suspend_mapping(struct pci_dev *pdev)
 {
 	struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);