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path: root/drivers/pci/controller/dwc/pcie-armada8k.c
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Diffstat (limited to 'drivers/pci/controller/dwc/pcie-armada8k.c')
-rw-r--r--drivers/pci/controller/dwc/pcie-armada8k.c282
1 files changed, 282 insertions, 0 deletions
diff --git a/drivers/pci/controller/dwc/pcie-armada8k.c b/drivers/pci/controller/dwc/pcie-armada8k.c
new file mode 100644
index 000000000000..072fd7ecc29f
--- /dev/null
+++ b/drivers/pci/controller/dwc/pcie-armada8k.c
@@ -0,0 +1,282 @@
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCIe host controller driver for Marvell Armada-8K SoCs
4 *
5 * Armada-8K PCIe Glue Layer Source Code
6 *
7 * Copyright (C) 2016 Marvell Technology Group Ltd.
8 *
9 * Author: Yehuda Yitshak <yehuday@marvell.com>
10 * Author: Shadi Ammouri <shadi@marvell.com>
11 */
12
13#include <linux/clk.h>
14#include <linux/delay.h>
15#include <linux/interrupt.h>
16#include <linux/kernel.h>
17#include <linux/init.h>
18#include <linux/of.h>
19#include <linux/pci.h>
20#include <linux/phy/phy.h>
21#include <linux/platform_device.h>
22#include <linux/resource.h>
23#include <linux/of_pci.h>
24#include <linux/of_irq.h>
25
26#include "pcie-designware.h"
27
28struct armada8k_pcie {
29 struct dw_pcie *pci;
30 struct clk *clk;
31 struct clk *clk_reg;
32};
33
34#define PCIE_VENDOR_REGS_OFFSET 0x8000
35
36#define PCIE_GLOBAL_CONTROL_REG (PCIE_VENDOR_REGS_OFFSET + 0x0)
37#define PCIE_APP_LTSSM_EN BIT(2)
38#define PCIE_DEVICE_TYPE_SHIFT 4
39#define PCIE_DEVICE_TYPE_MASK 0xF
40#define PCIE_DEVICE_TYPE_RC 0x4 /* Root complex */
41
42#define PCIE_GLOBAL_STATUS_REG (PCIE_VENDOR_REGS_OFFSET + 0x8)
43#define PCIE_GLB_STS_RDLH_LINK_UP BIT(1)
44#define PCIE_GLB_STS_PHY_LINK_UP BIT(9)
45
46#define PCIE_GLOBAL_INT_CAUSE1_REG (PCIE_VENDOR_REGS_OFFSET + 0x1C)
47#define PCIE_GLOBAL_INT_MASK1_REG (PCIE_VENDOR_REGS_OFFSET + 0x20)
48#define PCIE_INT_A_ASSERT_MASK BIT(9)
49#define PCIE_INT_B_ASSERT_MASK BIT(10)
50#define PCIE_INT_C_ASSERT_MASK BIT(11)
51#define PCIE_INT_D_ASSERT_MASK BIT(12)
52
53#define PCIE_ARCACHE_TRC_REG (PCIE_VENDOR_REGS_OFFSET + 0x50)
54#define PCIE_AWCACHE_TRC_REG (PCIE_VENDOR_REGS_OFFSET + 0x54)
55#define PCIE_ARUSER_REG (PCIE_VENDOR_REGS_OFFSET + 0x5C)
56#define PCIE_AWUSER_REG (PCIE_VENDOR_REGS_OFFSET + 0x60)
57/*
58 * AR/AW Cache defauls: Normal memory, Write-Back, Read / Write
59 * allocate
60 */
61#define ARCACHE_DEFAULT_VALUE 0x3511
62#define AWCACHE_DEFAULT_VALUE 0x5311
63
64#define DOMAIN_OUTER_SHAREABLE 0x2
65#define AX_USER_DOMAIN_MASK 0x3
66#define AX_USER_DOMAIN_SHIFT 4
67
68#define to_armada8k_pcie(x) dev_get_drvdata((x)->dev)
69
70static int armada8k_pcie_link_up(struct dw_pcie *pci)
71{
72 u32 reg;
73 u32 mask = PCIE_GLB_STS_RDLH_LINK_UP | PCIE_GLB_STS_PHY_LINK_UP;
74
75 reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_STATUS_REG);
76
77 if ((reg & mask) == mask)
78 return 1;
79
80 dev_dbg(pci->dev, "No link detected (Global-Status: 0x%08x).\n", reg);
81 return 0;
82}
83
84static void armada8k_pcie_establish_link(struct armada8k_pcie *pcie)
85{
86 struct dw_pcie *pci = pcie->pci;
87 u32 reg;
88
89 if (!dw_pcie_link_up(pci)) {
90 /* Disable LTSSM state machine to enable configuration */
91 reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG);
92 reg &= ~(PCIE_APP_LTSSM_EN);
93 dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg);
94 }
95
96 /* Set the device to root complex mode */
97 reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG);
98 reg &= ~(PCIE_DEVICE_TYPE_MASK << PCIE_DEVICE_TYPE_SHIFT);
99 reg |= PCIE_DEVICE_TYPE_RC << PCIE_DEVICE_TYPE_SHIFT;
100 dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg);
101
102 /* Set the PCIe master AxCache attributes */
103 dw_pcie_writel_dbi(pci, PCIE_ARCACHE_TRC_REG, ARCACHE_DEFAULT_VALUE);
104 dw_pcie_writel_dbi(pci, PCIE_AWCACHE_TRC_REG, AWCACHE_DEFAULT_VALUE);
105
106 /* Set the PCIe master AxDomain attributes */
107 reg = dw_pcie_readl_dbi(pci, PCIE_ARUSER_REG);
108 reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT);
109 reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT;
110 dw_pcie_writel_dbi(pci, PCIE_ARUSER_REG, reg);
111
112 reg = dw_pcie_readl_dbi(pci, PCIE_AWUSER_REG);
113 reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT);
114 reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT;
115 dw_pcie_writel_dbi(pci, PCIE_AWUSER_REG, reg);
116
117 /* Enable INT A-D interrupts */
118 reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_MASK1_REG);
119 reg |= PCIE_INT_A_ASSERT_MASK | PCIE_INT_B_ASSERT_MASK |
120 PCIE_INT_C_ASSERT_MASK | PCIE_INT_D_ASSERT_MASK;
121 dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_MASK1_REG, reg);
122
123 if (!dw_pcie_link_up(pci)) {
124 /* Configuration done. Start LTSSM */
125 reg = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_CONTROL_REG);
126 reg |= PCIE_APP_LTSSM_EN;
127 dw_pcie_writel_dbi(pci, PCIE_GLOBAL_CONTROL_REG, reg);
128 }
129
130 /* Wait until the link becomes active again */
131 if (dw_pcie_wait_for_link(pci))
132 dev_err(pci->dev, "Link not up after reconfiguration\n");
133}
134
135static int armada8k_pcie_host_init(struct pcie_port *pp)
136{
137 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
138 struct armada8k_pcie *pcie = to_armada8k_pcie(pci);
139
140 dw_pcie_setup_rc(pp);
141 armada8k_pcie_establish_link(pcie);
142
143 return 0;
144}
145
146static irqreturn_t armada8k_pcie_irq_handler(int irq, void *arg)
147{
148 struct armada8k_pcie *pcie = arg;
149 struct dw_pcie *pci = pcie->pci;
150 u32 val;
151
152 /*
153 * Interrupts are directly handled by the device driver of the
154 * PCI device. However, they are also latched into the PCIe
155 * controller, so we simply discard them.
156 */
157 val = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG);
158 dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG, val);
159
160 return IRQ_HANDLED;
161}
162
163static const struct dw_pcie_host_ops armada8k_pcie_host_ops = {
164 .host_init = armada8k_pcie_host_init,
165};
166
167static int armada8k_add_pcie_port(struct armada8k_pcie *pcie,
168 struct platform_device *pdev)
169{
170 struct dw_pcie *pci = pcie->pci;
171 struct pcie_port *pp = &pci->pp;
172 struct device *dev = &pdev->dev;
173 int ret;
174
175 pp->root_bus_nr = -1;
176 pp->ops = &armada8k_pcie_host_ops;
177
178 pp->irq = platform_get_irq(pdev, 0);
179 if (pp->irq < 0) {
180 dev_err(dev, "failed to get irq for port\n");
181 return pp->irq;
182 }
183
184 ret = devm_request_irq(dev, pp->irq, armada8k_pcie_irq_handler,
185 IRQF_SHARED, "armada8k-pcie", pcie);
186 if (ret) {
187 dev_err(dev, "failed to request irq %d\n", pp->irq);
188 return ret;
189 }
190
191 ret = dw_pcie_host_init(pp);
192 if (ret) {
193 dev_err(dev, "failed to initialize host: %d\n", ret);
194 return ret;
195 }
196
197 return 0;
198}
199
200static const struct dw_pcie_ops dw_pcie_ops = {
201 .link_up = armada8k_pcie_link_up,
202};
203
204static int armada8k_pcie_probe(struct platform_device *pdev)
205{
206 struct dw_pcie *pci;
207 struct armada8k_pcie *pcie;
208 struct device *dev = &pdev->dev;
209 struct resource *base;
210 int ret;
211
212 pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
213 if (!pcie)
214 return -ENOMEM;
215
216 pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
217 if (!pci)
218 return -ENOMEM;
219
220 pci->dev = dev;
221 pci->ops = &dw_pcie_ops;
222
223 pcie->pci = pci;
224
225 pcie->clk = devm_clk_get(dev, NULL);
226 if (IS_ERR(pcie->clk))
227 return PTR_ERR(pcie->clk);
228
229 ret = clk_prepare_enable(pcie->clk);
230 if (ret)
231 return ret;
232
233 pcie->clk_reg = devm_clk_get(dev, "reg");
234 if (pcie->clk_reg == ERR_PTR(-EPROBE_DEFER)) {
235 ret = -EPROBE_DEFER;
236 goto fail;
237 }
238 if (!IS_ERR(pcie->clk_reg)) {
239 ret = clk_prepare_enable(pcie->clk_reg);
240 if (ret)
241 goto fail_clkreg;
242 }
243
244 /* Get the dw-pcie unit configuration/control registers base. */
245 base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl");
246 pci->dbi_base = devm_pci_remap_cfg_resource(dev, base);
247 if (IS_ERR(pci->dbi_base)) {
248 dev_err(dev, "couldn't remap regs base %p\n", base);
249 ret = PTR_ERR(pci->dbi_base);
250 goto fail_clkreg;
251 }
252
253 platform_set_drvdata(pdev, pcie);
254
255 ret = armada8k_add_pcie_port(pcie, pdev);
256 if (ret)
257 goto fail_clkreg;
258
259 return 0;
260
261fail_clkreg:
262 clk_disable_unprepare(pcie->clk_reg);
263fail:
264 clk_disable_unprepare(pcie->clk);
265
266 return ret;
267}
268
269static const struct of_device_id armada8k_pcie_of_match[] = {
270 { .compatible = "marvell,armada8k-pcie", },
271 {},
272};
273
274static struct platform_driver armada8k_pcie_driver = {
275 .probe = armada8k_pcie_probe,
276 .driver = {
277 .name = "armada8k-pcie",
278 .of_match_table = of_match_ptr(armada8k_pcie_of_match),
279 .suppress_bind_attrs = true,
280 },
281};
282builtin_platform_driver(armada8k_pcie_driver);