diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-12 18:05:02 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-12 18:05:02 -0400 |
commit | 38da0d6888a6bccd3ae93227aa9f29537f8bd5f9 (patch) | |
tree | 64c7c1d008460f05b579110a7e40b6c796fb1578 /drivers/pci/controller/pcie-altera-msi.c | |
parent | 19785cf93b6c4252981894394f2dbd35c5e5d1ec (diff) | |
parent | ce4c7b241227ed49c0b6f0f1867653e1ee0007ef (diff) |
Merge tag 'pci-v4.18-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull more PCI updates from Bjorn Helgaas:
- squash AER directory into drivers/pci/pcie/aer.c (Bjorn Helgaas)
- collect all native hardware drivers under drivers/pci/controller/
(Shawn Lin)
* tag 'pci-v4.18-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI/AER: Use "PCI Express" consistently in Kconfig text
PCI/AER: Hoist aerdrv.c, aer_inject.c up to drivers/pci/pcie/
PCI/AER: Squash Kconfig.debug into Kconfig
PCI/AER: Move private AER things to aerdrv.c
PCI/AER: Move aer_irq() declaration to portdrv.h
PCI/AER: Move pcie_aer_get_firmware_first() to portdrv.h
PCI/AER: Remove duplicate pcie_port_bus_type declaration
PCI/AER: Squash ecrc.c into aerdrv.c
PCI/AER: Squash aerdrv_acpi.c into aerdrv.c
PCI/AER: Squash aerdrv_errprint.c into aerdrv.c
PCI/AER: Squash aerdrv_core.c into aerdrv.c
PCI/AER: Reorder code to group probe/remove stuff together
PCI/AER: Remove forward declarations
PCI: Collect all native drivers under drivers/pci/controller/
Diffstat (limited to 'drivers/pci/controller/pcie-altera-msi.c')
-rw-r--r-- | drivers/pci/controller/pcie-altera-msi.c | 291 |
1 files changed, 291 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-altera-msi.c b/drivers/pci/controller/pcie-altera-msi.c new file mode 100644 index 000000000000..025ef7d9a046 --- /dev/null +++ b/drivers/pci/controller/pcie-altera-msi.c | |||
@@ -0,0 +1,291 @@ | |||
1 | // SPDX-License-Identifier: GPL-2.0 | ||
2 | /* | ||
3 | * Altera PCIe MSI support | ||
4 | * | ||
5 | * Author: Ley Foon Tan <lftan@altera.com> | ||
6 | * | ||
7 | * Copyright Altera Corporation (C) 2013-2015. All rights reserved | ||
8 | */ | ||
9 | |||
10 | #include <linux/interrupt.h> | ||
11 | #include <linux/irqchip/chained_irq.h> | ||
12 | #include <linux/init.h> | ||
13 | #include <linux/msi.h> | ||
14 | #include <linux/of_address.h> | ||
15 | #include <linux/of_irq.h> | ||
16 | #include <linux/of_pci.h> | ||
17 | #include <linux/pci.h> | ||
18 | #include <linux/platform_device.h> | ||
19 | #include <linux/slab.h> | ||
20 | |||
21 | #define MSI_STATUS 0x0 | ||
22 | #define MSI_ERROR 0x4 | ||
23 | #define MSI_INTMASK 0x8 | ||
24 | |||
25 | #define MAX_MSI_VECTORS 32 | ||
26 | |||
27 | struct altera_msi { | ||
28 | DECLARE_BITMAP(used, MAX_MSI_VECTORS); | ||
29 | struct mutex lock; /* protect "used" bitmap */ | ||
30 | struct platform_device *pdev; | ||
31 | struct irq_domain *msi_domain; | ||
32 | struct irq_domain *inner_domain; | ||
33 | void __iomem *csr_base; | ||
34 | void __iomem *vector_base; | ||
35 | phys_addr_t vector_phy; | ||
36 | u32 num_of_vectors; | ||
37 | int irq; | ||
38 | }; | ||
39 | |||
40 | static inline void msi_writel(struct altera_msi *msi, const u32 value, | ||
41 | const u32 reg) | ||
42 | { | ||
43 | writel_relaxed(value, msi->csr_base + reg); | ||
44 | } | ||
45 | |||
46 | static inline u32 msi_readl(struct altera_msi *msi, const u32 reg) | ||
47 | { | ||
48 | return readl_relaxed(msi->csr_base + reg); | ||
49 | } | ||
50 | |||
51 | static void altera_msi_isr(struct irq_desc *desc) | ||
52 | { | ||
53 | struct irq_chip *chip = irq_desc_get_chip(desc); | ||
54 | struct altera_msi *msi; | ||
55 | unsigned long status; | ||
56 | u32 bit; | ||
57 | u32 virq; | ||
58 | |||
59 | chained_irq_enter(chip, desc); | ||
60 | msi = irq_desc_get_handler_data(desc); | ||
61 | |||
62 | while ((status = msi_readl(msi, MSI_STATUS)) != 0) { | ||
63 | for_each_set_bit(bit, &status, msi->num_of_vectors) { | ||
64 | /* Dummy read from vector to clear the interrupt */ | ||
65 | readl_relaxed(msi->vector_base + (bit * sizeof(u32))); | ||
66 | |||
67 | virq = irq_find_mapping(msi->inner_domain, bit); | ||
68 | if (virq) | ||
69 | generic_handle_irq(virq); | ||
70 | else | ||
71 | dev_err(&msi->pdev->dev, "unexpected MSI\n"); | ||
72 | } | ||
73 | } | ||
74 | |||
75 | chained_irq_exit(chip, desc); | ||
76 | } | ||
77 | |||
78 | static struct irq_chip altera_msi_irq_chip = { | ||
79 | .name = "Altera PCIe MSI", | ||
80 | .irq_mask = pci_msi_mask_irq, | ||
81 | .irq_unmask = pci_msi_unmask_irq, | ||
82 | }; | ||
83 | |||
84 | static struct msi_domain_info altera_msi_domain_info = { | ||
85 | .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | | ||
86 | MSI_FLAG_PCI_MSIX), | ||
87 | .chip = &altera_msi_irq_chip, | ||
88 | }; | ||
89 | |||
90 | static void altera_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) | ||
91 | { | ||
92 | struct altera_msi *msi = irq_data_get_irq_chip_data(data); | ||
93 | phys_addr_t addr = msi->vector_phy + (data->hwirq * sizeof(u32)); | ||
94 | |||
95 | msg->address_lo = lower_32_bits(addr); | ||
96 | msg->address_hi = upper_32_bits(addr); | ||
97 | msg->data = data->hwirq; | ||
98 | |||
99 | dev_dbg(&msi->pdev->dev, "msi#%d address_hi %#x address_lo %#x\n", | ||
100 | (int)data->hwirq, msg->address_hi, msg->address_lo); | ||
101 | } | ||
102 | |||
103 | static int altera_msi_set_affinity(struct irq_data *irq_data, | ||
104 | const struct cpumask *mask, bool force) | ||
105 | { | ||
106 | return -EINVAL; | ||
107 | } | ||
108 | |||
109 | static struct irq_chip altera_msi_bottom_irq_chip = { | ||
110 | .name = "Altera MSI", | ||
111 | .irq_compose_msi_msg = altera_compose_msi_msg, | ||
112 | .irq_set_affinity = altera_msi_set_affinity, | ||
113 | }; | ||
114 | |||
115 | static int altera_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, | ||
116 | unsigned int nr_irqs, void *args) | ||
117 | { | ||
118 | struct altera_msi *msi = domain->host_data; | ||
119 | unsigned long bit; | ||
120 | u32 mask; | ||
121 | |||
122 | WARN_ON(nr_irqs != 1); | ||
123 | mutex_lock(&msi->lock); | ||
124 | |||
125 | bit = find_first_zero_bit(msi->used, msi->num_of_vectors); | ||
126 | if (bit >= msi->num_of_vectors) { | ||
127 | mutex_unlock(&msi->lock); | ||
128 | return -ENOSPC; | ||
129 | } | ||
130 | |||
131 | set_bit(bit, msi->used); | ||
132 | |||
133 | mutex_unlock(&msi->lock); | ||
134 | |||
135 | irq_domain_set_info(domain, virq, bit, &altera_msi_bottom_irq_chip, | ||
136 | domain->host_data, handle_simple_irq, | ||
137 | NULL, NULL); | ||
138 | |||
139 | mask = msi_readl(msi, MSI_INTMASK); | ||
140 | mask |= 1 << bit; | ||
141 | msi_writel(msi, mask, MSI_INTMASK); | ||
142 | |||
143 | return 0; | ||
144 | } | ||
145 | |||
146 | static void altera_irq_domain_free(struct irq_domain *domain, | ||
147 | unsigned int virq, unsigned int nr_irqs) | ||
148 | { | ||
149 | struct irq_data *d = irq_domain_get_irq_data(domain, virq); | ||
150 | struct altera_msi *msi = irq_data_get_irq_chip_data(d); | ||
151 | u32 mask; | ||
152 | |||
153 | mutex_lock(&msi->lock); | ||
154 | |||
155 | if (!test_bit(d->hwirq, msi->used)) { | ||
156 | dev_err(&msi->pdev->dev, "trying to free unused MSI#%lu\n", | ||
157 | d->hwirq); | ||
158 | } else { | ||
159 | __clear_bit(d->hwirq, msi->used); | ||
160 | mask = msi_readl(msi, MSI_INTMASK); | ||
161 | mask &= ~(1 << d->hwirq); | ||
162 | msi_writel(msi, mask, MSI_INTMASK); | ||
163 | } | ||
164 | |||
165 | mutex_unlock(&msi->lock); | ||
166 | } | ||
167 | |||
168 | static const struct irq_domain_ops msi_domain_ops = { | ||
169 | .alloc = altera_irq_domain_alloc, | ||
170 | .free = altera_irq_domain_free, | ||
171 | }; | ||
172 | |||
173 | static int altera_allocate_domains(struct altera_msi *msi) | ||
174 | { | ||
175 | struct fwnode_handle *fwnode = of_node_to_fwnode(msi->pdev->dev.of_node); | ||
176 | |||
177 | msi->inner_domain = irq_domain_add_linear(NULL, msi->num_of_vectors, | ||
178 | &msi_domain_ops, msi); | ||
179 | if (!msi->inner_domain) { | ||
180 | dev_err(&msi->pdev->dev, "failed to create IRQ domain\n"); | ||
181 | return -ENOMEM; | ||
182 | } | ||
183 | |||
184 | msi->msi_domain = pci_msi_create_irq_domain(fwnode, | ||
185 | &altera_msi_domain_info, msi->inner_domain); | ||
186 | if (!msi->msi_domain) { | ||
187 | dev_err(&msi->pdev->dev, "failed to create MSI domain\n"); | ||
188 | irq_domain_remove(msi->inner_domain); | ||
189 | return -ENOMEM; | ||
190 | } | ||
191 | |||
192 | return 0; | ||
193 | } | ||
194 | |||
195 | static void altera_free_domains(struct altera_msi *msi) | ||
196 | { | ||
197 | irq_domain_remove(msi->msi_domain); | ||
198 | irq_domain_remove(msi->inner_domain); | ||
199 | } | ||
200 | |||
201 | static int altera_msi_remove(struct platform_device *pdev) | ||
202 | { | ||
203 | struct altera_msi *msi = platform_get_drvdata(pdev); | ||
204 | |||
205 | msi_writel(msi, 0, MSI_INTMASK); | ||
206 | irq_set_chained_handler(msi->irq, NULL); | ||
207 | irq_set_handler_data(msi->irq, NULL); | ||
208 | |||
209 | altera_free_domains(msi); | ||
210 | |||
211 | platform_set_drvdata(pdev, NULL); | ||
212 | return 0; | ||
213 | } | ||
214 | |||
215 | static int altera_msi_probe(struct platform_device *pdev) | ||
216 | { | ||
217 | struct altera_msi *msi; | ||
218 | struct device_node *np = pdev->dev.of_node; | ||
219 | struct resource *res; | ||
220 | int ret; | ||
221 | |||
222 | msi = devm_kzalloc(&pdev->dev, sizeof(struct altera_msi), | ||
223 | GFP_KERNEL); | ||
224 | if (!msi) | ||
225 | return -ENOMEM; | ||
226 | |||
227 | mutex_init(&msi->lock); | ||
228 | msi->pdev = pdev; | ||
229 | |||
230 | res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr"); | ||
231 | msi->csr_base = devm_ioremap_resource(&pdev->dev, res); | ||
232 | if (IS_ERR(msi->csr_base)) { | ||
233 | dev_err(&pdev->dev, "failed to map csr memory\n"); | ||
234 | return PTR_ERR(msi->csr_base); | ||
235 | } | ||
236 | |||
237 | res = platform_get_resource_byname(pdev, IORESOURCE_MEM, | ||
238 | "vector_slave"); | ||
239 | msi->vector_base = devm_ioremap_resource(&pdev->dev, res); | ||
240 | if (IS_ERR(msi->vector_base)) { | ||
241 | dev_err(&pdev->dev, "failed to map vector_slave memory\n"); | ||
242 | return PTR_ERR(msi->vector_base); | ||
243 | } | ||
244 | |||
245 | msi->vector_phy = res->start; | ||
246 | |||
247 | if (of_property_read_u32(np, "num-vectors", &msi->num_of_vectors)) { | ||
248 | dev_err(&pdev->dev, "failed to parse the number of vectors\n"); | ||
249 | return -EINVAL; | ||
250 | } | ||
251 | |||
252 | ret = altera_allocate_domains(msi); | ||
253 | if (ret) | ||
254 | return ret; | ||
255 | |||
256 | msi->irq = platform_get_irq(pdev, 0); | ||
257 | if (msi->irq < 0) { | ||
258 | dev_err(&pdev->dev, "failed to map IRQ: %d\n", msi->irq); | ||
259 | ret = msi->irq; | ||
260 | goto err; | ||
261 | } | ||
262 | |||
263 | irq_set_chained_handler_and_data(msi->irq, altera_msi_isr, msi); | ||
264 | platform_set_drvdata(pdev, msi); | ||
265 | |||
266 | return 0; | ||
267 | |||
268 | err: | ||
269 | altera_msi_remove(pdev); | ||
270 | return ret; | ||
271 | } | ||
272 | |||
273 | static const struct of_device_id altera_msi_of_match[] = { | ||
274 | { .compatible = "altr,msi-1.0", NULL }, | ||
275 | { }, | ||
276 | }; | ||
277 | |||
278 | static struct platform_driver altera_msi_driver = { | ||
279 | .driver = { | ||
280 | .name = "altera-msi", | ||
281 | .of_match_table = altera_msi_of_match, | ||
282 | }, | ||
283 | .probe = altera_msi_probe, | ||
284 | .remove = altera_msi_remove, | ||
285 | }; | ||
286 | |||
287 | static int __init altera_msi_init(void) | ||
288 | { | ||
289 | return platform_driver_register(&altera_msi_driver); | ||
290 | } | ||
291 | subsys_initcall(altera_msi_init); | ||