1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Qualcomm PCIe Endpoint controller driver
4 *
5 * Copyright (c) 2020, The Linux Foundation. All rights reserved.
6 * Author: Siddartha Mohanadoss <smohanad@codeaurora.org
7 *
8 * Copyright (c) 2021, Linaro Ltd.
9 * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org
10 */
11
12#include <linux/clk.h>
13#include <linux/debugfs.h>
14#include <linux/delay.h>
15#include <linux/gpio/consumer.h>
16#include <linux/interconnect.h>
17#include <linux/mfd/syscon.h>
18#include <linux/phy/pcie.h>
19#include <linux/phy/phy.h>
20#include <linux/platform_device.h>
21#include <linux/pm_domain.h>
22#include <linux/regmap.h>
23#include <linux/reset.h>
24#include <linux/module.h>
25
26#include "../../pci.h"
27#include "pcie-designware.h"
28
29/* PARF registers */
30#define PARF_SYS_CTRL 0x00
31#define PARF_DB_CTRL 0x10
32#define PARF_PM_CTRL 0x20
33#define PARF_MHI_CLOCK_RESET_CTRL 0x174
34#define PARF_MHI_BASE_ADDR_LOWER 0x178
35#define PARF_MHI_BASE_ADDR_UPPER 0x17c
36#define PARF_DEBUG_INT_EN 0x190
37#define PARF_AXI_MSTR_RD_HALT_NO_WRITES 0x1a4
38#define PARF_AXI_MSTR_WR_ADDR_HALT 0x1a8
39#define PARF_Q2A_FLUSH 0x1ac
40#define PARF_LTSSM 0x1b0
41#define PARF_CFG_BITS 0x210
42#define PARF_INT_ALL_STATUS 0x224
43#define PARF_INT_ALL_CLEAR 0x228
44#define PARF_INT_ALL_MASK 0x22c
45#define PARF_SLV_ADDR_MSB_CTRL 0x2c0
46#define PARF_DBI_BASE_ADDR 0x350
47#define PARF_DBI_BASE_ADDR_HI 0x354
48#define PARF_SLV_ADDR_SPACE_SIZE 0x358
49#define PARF_SLV_ADDR_SPACE_SIZE_HI 0x35c
50#define PARF_ATU_BASE_ADDR 0x634
51#define PARF_ATU_BASE_ADDR_HI 0x638
52#define PARF_SRIS_MODE 0x644
53#define PARF_DEBUG_CNT_PM_LINKST_IN_L2 0xc04
54#define PARF_DEBUG_CNT_PM_LINKST_IN_L1 0xc0c
55#define PARF_DEBUG_CNT_PM_LINKST_IN_L0S 0xc10
56#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1 0xc84
57#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2 0xc88
58#define PARF_DEVICE_TYPE 0x1000
59#define PARF_BDF_TO_SID_CFG 0x2c00
60
61/* PARF_INT_ALL_{STATUS/CLEAR/MASK} register fields */
62#define PARF_INT_ALL_LINK_DOWN BIT(1)
63#define PARF_INT_ALL_BME BIT(2)
64#define PARF_INT_ALL_PM_TURNOFF BIT(3)
65#define PARF_INT_ALL_DEBUG BIT(4)
66#define PARF_INT_ALL_LTR BIT(5)
67#define PARF_INT_ALL_MHI_Q6 BIT(6)
68#define PARF_INT_ALL_MHI_A7 BIT(7)
69#define PARF_INT_ALL_DSTATE_CHANGE BIT(8)
70#define PARF_INT_ALL_L1SUB_TIMEOUT BIT(9)
71#define PARF_INT_ALL_MMIO_WRITE BIT(10)
72#define PARF_INT_ALL_CFG_WRITE BIT(11)
73#define PARF_INT_ALL_BRIDGE_FLUSH_N BIT(12)
74#define PARF_INT_ALL_LINK_UP BIT(13)
75#define PARF_INT_ALL_AER_LEGACY BIT(14)
76#define PARF_INT_ALL_PLS_ERR BIT(15)
77#define PARF_INT_ALL_PME_LEGACY BIT(16)
78#define PARF_INT_ALL_PLS_PME BIT(17)
79#define PARF_INT_ALL_EDMA BIT(22)
80
81/* PARF_BDF_TO_SID_CFG register fields */
82#define PARF_BDF_TO_SID_BYPASS BIT(0)
83
84/* PARF_DEBUG_INT_EN register fields */
85#define PARF_DEBUG_INT_PM_DSTATE_CHANGE BIT(1)
86#define PARF_DEBUG_INT_CFG_BUS_MASTER_EN BIT(2)
87#define PARF_DEBUG_INT_RADM_PM_TURNOFF BIT(3)
88
89/* PARF_DEVICE_TYPE register fields */
90#define PARF_DEVICE_TYPE_EP 0x0
91
92/* PARF_PM_CTRL register fields */
93#define PARF_PM_CTRL_REQ_EXIT_L1 BIT(1)
94#define PARF_PM_CTRL_READY_ENTR_L23 BIT(2)
95#define PARF_PM_CTRL_REQ_NOT_ENTR_L1 BIT(5)
96
97/* PARF_MHI_CLOCK_RESET_CTRL fields */
98#define PARF_MSTR_AXI_CLK_EN BIT(1)
99
100/* PARF_AXI_MSTR_RD_HALT_NO_WRITES register fields */
101#define PARF_AXI_MSTR_RD_HALT_NO_WRITE_EN BIT(0)
102
103/* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
104#define PARF_AXI_MSTR_WR_ADDR_HALT_EN BIT(31)
105
106/* PARF_Q2A_FLUSH register fields */
107#define PARF_Q2A_FLUSH_EN BIT(16)
108
109/* PARF_SYS_CTRL register fields */
110#define PARF_SYS_CTRL_AUX_PWR_DET BIT(4)
111#define PARF_SYS_CTRL_CORE_CLK_CGC_DIS BIT(6)
112#define PARF_SYS_CTRL_MSTR_ACLK_CGC_DIS BIT(10)
113#define PARF_SYS_CTRL_SLV_DBI_WAKE_DISABLE BIT(11)
114
115/* PARF_DB_CTRL register fields */
116#define PARF_DB_CTRL_INSR_DBNCR_BLOCK BIT(0)
117#define PARF_DB_CTRL_RMVL_DBNCR_BLOCK BIT(1)
118#define PARF_DB_CTRL_DBI_WKP_BLOCK BIT(4)
119#define PARF_DB_CTRL_SLV_WKP_BLOCK BIT(5)
120#define PARF_DB_CTRL_MST_WKP_BLOCK BIT(6)
121
122/* PARF_CFG_BITS register fields */
123#define PARF_CFG_BITS_REQ_EXIT_L1SS_MSI_LTR_EN BIT(1)
124
125/* ELBI registers */
126#define ELBI_SYS_STTS 0x08
127#define ELBI_CS2_ENABLE 0xa4
128
129/* DBI registers */
130#define DBI_CON_STATUS 0x44
131
132/* DBI register fields */
133#define DBI_CON_STATUS_POWER_STATE_MASK GENMASK(1, 0)
134
135#define XMLH_LINK_UP 0x400
136#define CORE_RESET_TIME_US_MIN 1000
137#define CORE_RESET_TIME_US_MAX 1005
138#define WAKE_DELAY_US 2000 /* 2 ms */
139
140#define QCOM_PCIE_LINK_SPEED_TO_BW(speed) \
141 Mbps_to_icc(PCIE_SPEED2MBS_ENC(pcie_link_speed[speed]))
142
143#define to_pcie_ep(x) dev_get_drvdata((x)->dev)
144
145enum qcom_pcie_ep_link_status {
146 QCOM_PCIE_EP_LINK_DISABLED,
147 QCOM_PCIE_EP_LINK_ENABLED,
148 QCOM_PCIE_EP_LINK_UP,
149 QCOM_PCIE_EP_LINK_DOWN,
150};
151
152/**
153 * struct qcom_pcie_ep - Qualcomm PCIe Endpoint Controller
154 * @pci: Designware PCIe controller struct
155 * @parf: Qualcomm PCIe specific PARF register base
156 * @elbi: Designware PCIe specific ELBI register base
157 * @mmio: MMIO register base
158 * @perst_map: PERST regmap
159 * @mmio_res: MMIO region resource
160 * @core_reset: PCIe Endpoint core reset
161 * @reset: PERST# GPIO
162 * @wake: WAKE# GPIO
163 * @phy: PHY controller block
164 * @debugfs: PCIe Endpoint Debugfs directory
165 * @icc_mem: Handle to an interconnect path between PCIe and MEM
166 * @clks: PCIe clocks
167 * @num_clks: PCIe clocks count
168 * @perst_en: Flag for PERST enable
169 * @perst_sep_en: Flag for PERST separation enable
170 * @link_status: PCIe Link status
171 * @global_irq: Qualcomm PCIe specific Global IRQ
172 * @perst_irq: PERST# IRQ
173 */
174struct qcom_pcie_ep {
175 struct dw_pcie pci;
176
177 void __iomem *parf;
178 void __iomem *elbi;
179 void __iomem *mmio;
180 struct regmap *perst_map;
181 struct resource *mmio_res;
182
183 struct reset_control *core_reset;
184 struct gpio_desc *reset;
185 struct gpio_desc *wake;
186 struct phy *phy;
187 struct dentry *debugfs;
188
189 struct icc_path *icc_mem;
190
191 struct clk_bulk_data *clks;
192 int num_clks;
193
194 u32 perst_en;
195 u32 perst_sep_en;
196
197 enum qcom_pcie_ep_link_status link_status;
198 int global_irq;
199 int perst_irq;
200};
201
202static int qcom_pcie_ep_core_reset(struct qcom_pcie_ep *pcie_ep)
203{
204 struct dw_pcie *pci = &pcie_ep->pci;
205 struct device *dev = pci->dev;
206 int ret;
207
208 ret = reset_control_assert(rstc: pcie_ep->core_reset);
209 if (ret) {
210 dev_err(dev, "Cannot assert core reset\n");
211 return ret;
212 }
213
214 usleep_range(CORE_RESET_TIME_US_MIN, CORE_RESET_TIME_US_MAX);
215
216 ret = reset_control_deassert(rstc: pcie_ep->core_reset);
217 if (ret) {
218 dev_err(dev, "Cannot de-assert core reset\n");
219 return ret;
220 }
221
222 usleep_range(CORE_RESET_TIME_US_MIN, CORE_RESET_TIME_US_MAX);
223
224 return 0;
225}
226
227/*
228 * Delatch PERST_EN and PERST_SEPARATION_ENABLE with TCSR to avoid
229 * device reset during host reboot and hibernation. The driver is
230 * expected to handle this situation.
231 */
232static void qcom_pcie_ep_configure_tcsr(struct qcom_pcie_ep *pcie_ep)
233{
234 if (pcie_ep->perst_map) {
235 regmap_write(map: pcie_ep->perst_map, reg: pcie_ep->perst_en, val: 0);
236 regmap_write(map: pcie_ep->perst_map, reg: pcie_ep->perst_sep_en, val: 0);
237 }
238}
239
240static int qcom_pcie_dw_link_up(struct dw_pcie *pci)
241{
242 struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
243 u32 reg;
244
245 reg = readl_relaxed(pcie_ep->elbi + ELBI_SYS_STTS);
246
247 return reg & XMLH_LINK_UP;
248}
249
250static int qcom_pcie_dw_start_link(struct dw_pcie *pci)
251{
252 struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
253
254 enable_irq(irq: pcie_ep->perst_irq);
255
256 return 0;
257}
258
259static void qcom_pcie_dw_stop_link(struct dw_pcie *pci)
260{
261 struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
262
263 disable_irq(irq: pcie_ep->perst_irq);
264}
265
266static void qcom_pcie_dw_write_dbi2(struct dw_pcie *pci, void __iomem *base,
267 u32 reg, size_t size, u32 val)
268{
269 struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
270 int ret;
271
272 writel(val: 1, addr: pcie_ep->elbi + ELBI_CS2_ENABLE);
273
274 ret = dw_pcie_write(addr: pci->dbi_base2 + reg, size, val);
275 if (ret)
276 dev_err(pci->dev, "Failed to write DBI2 register (0x%x): %d\n", reg, ret);
277
278 writel(val: 0, addr: pcie_ep->elbi + ELBI_CS2_ENABLE);
279}
280
281static void qcom_pcie_ep_icc_update(struct qcom_pcie_ep *pcie_ep)
282{
283 struct dw_pcie *pci = &pcie_ep->pci;
284 u32 offset, status;
285 int speed, width;
286 int ret;
287
288 if (!pcie_ep->icc_mem)
289 return;
290
291 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
292 status = readw(addr: pci->dbi_base + offset + PCI_EXP_LNKSTA);
293
294 speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
295 width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
296
297 ret = icc_set_bw(path: pcie_ep->icc_mem, avg_bw: 0, peak_bw: width * QCOM_PCIE_LINK_SPEED_TO_BW(speed));
298 if (ret)
299 dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
300 ret);
301}
302
303static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep)
304{
305 struct dw_pcie *pci = &pcie_ep->pci;
306 int ret;
307
308 ret = clk_bulk_prepare_enable(num_clks: pcie_ep->num_clks, clks: pcie_ep->clks);
309 if (ret)
310 return ret;
311
312 ret = qcom_pcie_ep_core_reset(pcie_ep);
313 if (ret)
314 goto err_disable_clk;
315
316 ret = phy_init(phy: pcie_ep->phy);
317 if (ret)
318 goto err_disable_clk;
319
320 ret = phy_set_mode_ext(phy: pcie_ep->phy, mode: PHY_MODE_PCIE, PHY_MODE_PCIE_EP);
321 if (ret)
322 goto err_phy_exit;
323
324 ret = phy_power_on(phy: pcie_ep->phy);
325 if (ret)
326 goto err_phy_exit;
327
328 /*
329 * Some Qualcomm platforms require interconnect bandwidth constraints
330 * to be set before enabling interconnect clocks.
331 *
332 * Set an initial peak bandwidth corresponding to single-lane Gen 1
333 * for the pcie-mem path.
334 */
335 ret = icc_set_bw(path: pcie_ep->icc_mem, avg_bw: 0, QCOM_PCIE_LINK_SPEED_TO_BW(1));
336 if (ret) {
337 dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
338 ret);
339 goto err_phy_off;
340 }
341
342 return 0;
343
344err_phy_off:
345 phy_power_off(phy: pcie_ep->phy);
346err_phy_exit:
347 phy_exit(phy: pcie_ep->phy);
348err_disable_clk:
349 clk_bulk_disable_unprepare(num_clks: pcie_ep->num_clks, clks: pcie_ep->clks);
350
351 return ret;
352}
353
354static void qcom_pcie_disable_resources(struct qcom_pcie_ep *pcie_ep)
355{
356 icc_set_bw(path: pcie_ep->icc_mem, avg_bw: 0, peak_bw: 0);
357 phy_power_off(phy: pcie_ep->phy);
358 phy_exit(phy: pcie_ep->phy);
359 clk_bulk_disable_unprepare(num_clks: pcie_ep->num_clks, clks: pcie_ep->clks);
360}
361
362static int qcom_pcie_perst_deassert(struct dw_pcie *pci)
363{
364 struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
365 struct device *dev = pci->dev;
366 u32 val, offset;
367 int ret;
368
369 ret = qcom_pcie_enable_resources(pcie_ep);
370 if (ret) {
371 dev_err(dev, "Failed to enable resources: %d\n", ret);
372 return ret;
373 }
374
375 /* Assert WAKE# to RC to indicate device is ready */
376 gpiod_set_value_cansleep(desc: pcie_ep->wake, value: 1);
377 usleep_range(WAKE_DELAY_US, WAKE_DELAY_US + 500);
378 gpiod_set_value_cansleep(desc: pcie_ep->wake, value: 0);
379
380 qcom_pcie_ep_configure_tcsr(pcie_ep);
381
382 /* Disable BDF to SID mapping */
383 val = readl_relaxed(pcie_ep->parf + PARF_BDF_TO_SID_CFG);
384 val |= PARF_BDF_TO_SID_BYPASS;
385 writel_relaxed(val, pcie_ep->parf + PARF_BDF_TO_SID_CFG);
386
387 /* Enable debug IRQ */
388 val = readl_relaxed(pcie_ep->parf + PARF_DEBUG_INT_EN);
389 val |= PARF_DEBUG_INT_RADM_PM_TURNOFF |
390 PARF_DEBUG_INT_CFG_BUS_MASTER_EN |
391 PARF_DEBUG_INT_PM_DSTATE_CHANGE;
392 writel_relaxed(val, pcie_ep->parf + PARF_DEBUG_INT_EN);
393
394 /* Configure PCIe to endpoint mode */
395 writel_relaxed(PARF_DEVICE_TYPE_EP, pcie_ep->parf + PARF_DEVICE_TYPE);
396
397 /* Allow entering L1 state */
398 val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
399 val &= ~PARF_PM_CTRL_REQ_NOT_ENTR_L1;
400 writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
401
402 /* Read halts write */
403 val = readl_relaxed(pcie_ep->parf + PARF_AXI_MSTR_RD_HALT_NO_WRITES);
404 val &= ~PARF_AXI_MSTR_RD_HALT_NO_WRITE_EN;
405 writel_relaxed(val, pcie_ep->parf + PARF_AXI_MSTR_RD_HALT_NO_WRITES);
406
407 /* Write after write halt */
408 val = readl_relaxed(pcie_ep->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
409 val |= PARF_AXI_MSTR_WR_ADDR_HALT_EN;
410 writel_relaxed(val, pcie_ep->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
411
412 /* Q2A flush disable */
413 val = readl_relaxed(pcie_ep->parf + PARF_Q2A_FLUSH);
414 val &= ~PARF_Q2A_FLUSH_EN;
415 writel_relaxed(val, pcie_ep->parf + PARF_Q2A_FLUSH);
416
417 /*
418 * Disable Master AXI clock during idle. Do not allow DBI access
419 * to take the core out of L1. Disable core clock gating that
420 * gates PIPE clock from propagating to core clock. Report to the
421 * host that Vaux is present.
422 */
423 val = readl_relaxed(pcie_ep->parf + PARF_SYS_CTRL);
424 val &= ~PARF_SYS_CTRL_MSTR_ACLK_CGC_DIS;
425 val |= PARF_SYS_CTRL_SLV_DBI_WAKE_DISABLE |
426 PARF_SYS_CTRL_CORE_CLK_CGC_DIS |
427 PARF_SYS_CTRL_AUX_PWR_DET;
428 writel_relaxed(val, pcie_ep->parf + PARF_SYS_CTRL);
429
430 /* Disable the debouncers */
431 val = readl_relaxed(pcie_ep->parf + PARF_DB_CTRL);
432 val |= PARF_DB_CTRL_INSR_DBNCR_BLOCK | PARF_DB_CTRL_RMVL_DBNCR_BLOCK |
433 PARF_DB_CTRL_DBI_WKP_BLOCK | PARF_DB_CTRL_SLV_WKP_BLOCK |
434 PARF_DB_CTRL_MST_WKP_BLOCK;
435 writel_relaxed(val, pcie_ep->parf + PARF_DB_CTRL);
436
437 /* Request to exit from L1SS for MSI and LTR MSG */
438 val = readl_relaxed(pcie_ep->parf + PARF_CFG_BITS);
439 val |= PARF_CFG_BITS_REQ_EXIT_L1SS_MSI_LTR_EN;
440 writel_relaxed(val, pcie_ep->parf + PARF_CFG_BITS);
441
442 dw_pcie_dbi_ro_wr_en(pci);
443
444 /* Set the L0s Exit Latency to 2us-4us = 0x6 */
445 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
446 val = dw_pcie_readl_dbi(pci, reg: offset + PCI_EXP_LNKCAP);
447 val &= ~PCI_EXP_LNKCAP_L0SEL;
448 val |= FIELD_PREP(PCI_EXP_LNKCAP_L0SEL, 0x6);
449 dw_pcie_writel_dbi(pci, reg: offset + PCI_EXP_LNKCAP, val);
450
451 /* Set the L1 Exit Latency to be 32us-64 us = 0x6 */
452 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
453 val = dw_pcie_readl_dbi(pci, reg: offset + PCI_EXP_LNKCAP);
454 val &= ~PCI_EXP_LNKCAP_L1EL;
455 val |= FIELD_PREP(PCI_EXP_LNKCAP_L1EL, 0x6);
456 dw_pcie_writel_dbi(pci, reg: offset + PCI_EXP_LNKCAP, val);
457
458 dw_pcie_dbi_ro_wr_dis(pci);
459
460 writel_relaxed(0, pcie_ep->parf + PARF_INT_ALL_MASK);
461 val = PARF_INT_ALL_LINK_DOWN | PARF_INT_ALL_BME |
462 PARF_INT_ALL_PM_TURNOFF | PARF_INT_ALL_DSTATE_CHANGE |
463 PARF_INT_ALL_LINK_UP | PARF_INT_ALL_EDMA;
464 writel_relaxed(val, pcie_ep->parf + PARF_INT_ALL_MASK);
465
466 ret = dw_pcie_ep_init_complete(ep: &pcie_ep->pci.ep);
467 if (ret) {
468 dev_err(dev, "Failed to complete initialization: %d\n", ret);
469 goto err_disable_resources;
470 }
471
472 /*
473 * The physical address of the MMIO region which is exposed as the BAR
474 * should be written to MHI BASE registers.
475 */
476 writel_relaxed(pcie_ep->mmio_res->start,
477 pcie_ep->parf + PARF_MHI_BASE_ADDR_LOWER);
478 writel_relaxed(0, pcie_ep->parf + PARF_MHI_BASE_ADDR_UPPER);
479
480 /* Gate Master AXI clock to MHI bus during L1SS */
481 val = readl_relaxed(pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL);
482 val &= ~PARF_MSTR_AXI_CLK_EN;
483 writel_relaxed(val, pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL);
484
485 dw_pcie_ep_init_notify(ep: &pcie_ep->pci.ep);
486
487 /* Enable LTSSM */
488 val = readl_relaxed(pcie_ep->parf + PARF_LTSSM);
489 val |= BIT(8);
490 writel_relaxed(val, pcie_ep->parf + PARF_LTSSM);
491
492 return 0;
493
494err_disable_resources:
495 qcom_pcie_disable_resources(pcie_ep);
496
497 return ret;
498}
499
500static void qcom_pcie_perst_assert(struct dw_pcie *pci)
501{
502 struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
503 struct device *dev = pci->dev;
504
505 if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED) {
506 dev_dbg(dev, "Link is already disabled\n");
507 return;
508 }
509
510 qcom_pcie_disable_resources(pcie_ep);
511 pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED;
512}
513
514/* Common DWC controller ops */
515static const struct dw_pcie_ops pci_ops = {
516 .link_up = qcom_pcie_dw_link_up,
517 .start_link = qcom_pcie_dw_start_link,
518 .stop_link = qcom_pcie_dw_stop_link,
519 .write_dbi2 = qcom_pcie_dw_write_dbi2,
520};
521
522static int qcom_pcie_ep_get_io_resources(struct platform_device *pdev,
523 struct qcom_pcie_ep *pcie_ep)
524{
525 struct device *dev = &pdev->dev;
526 struct dw_pcie *pci = &pcie_ep->pci;
527 struct device_node *syscon;
528 struct resource *res;
529 int ret;
530
531 pcie_ep->parf = devm_platform_ioremap_resource_byname(pdev, name: "parf");
532 if (IS_ERR(ptr: pcie_ep->parf))
533 return PTR_ERR(ptr: pcie_ep->parf);
534
535 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
536 pci->dbi_base = devm_pci_remap_cfg_resource(dev, res);
537 if (IS_ERR(ptr: pci->dbi_base))
538 return PTR_ERR(ptr: pci->dbi_base);
539 pci->dbi_base2 = pci->dbi_base;
540
541 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi");
542 pcie_ep->elbi = devm_pci_remap_cfg_resource(dev, res);
543 if (IS_ERR(ptr: pcie_ep->elbi))
544 return PTR_ERR(ptr: pcie_ep->elbi);
545
546 pcie_ep->mmio_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
547 "mmio");
548 if (!pcie_ep->mmio_res) {
549 dev_err(dev, "Failed to get mmio resource\n");
550 return -EINVAL;
551 }
552
553 pcie_ep->mmio = devm_pci_remap_cfg_resource(dev, res: pcie_ep->mmio_res);
554 if (IS_ERR(ptr: pcie_ep->mmio))
555 return PTR_ERR(ptr: pcie_ep->mmio);
556
557 syscon = of_parse_phandle(np: dev->of_node, phandle_name: "qcom,perst-regs", index: 0);
558 if (!syscon) {
559 dev_dbg(dev, "PERST separation not available\n");
560 return 0;
561 }
562
563 pcie_ep->perst_map = syscon_node_to_regmap(np: syscon);
564 of_node_put(node: syscon);
565 if (IS_ERR(ptr: pcie_ep->perst_map))
566 return PTR_ERR(ptr: pcie_ep->perst_map);
567
568 ret = of_property_read_u32_index(np: dev->of_node, propname: "qcom,perst-regs",
569 index: 1, out_value: &pcie_ep->perst_en);
570 if (ret < 0) {
571 dev_err(dev, "No Perst Enable offset in syscon\n");
572 return ret;
573 }
574
575 ret = of_property_read_u32_index(np: dev->of_node, propname: "qcom,perst-regs",
576 index: 2, out_value: &pcie_ep->perst_sep_en);
577 if (ret < 0) {
578 dev_err(dev, "No Perst Separation Enable offset in syscon\n");
579 return ret;
580 }
581
582 return 0;
583}
584
585static int qcom_pcie_ep_get_resources(struct platform_device *pdev,
586 struct qcom_pcie_ep *pcie_ep)
587{
588 struct device *dev = &pdev->dev;
589 int ret;
590
591 ret = qcom_pcie_ep_get_io_resources(pdev, pcie_ep);
592 if (ret) {
593 dev_err(dev, "Failed to get io resources %d\n", ret);
594 return ret;
595 }
596
597 pcie_ep->num_clks = devm_clk_bulk_get_all(dev, clks: &pcie_ep->clks);
598 if (pcie_ep->num_clks < 0) {
599 dev_err(dev, "Failed to get clocks\n");
600 return pcie_ep->num_clks;
601 }
602
603 pcie_ep->core_reset = devm_reset_control_get_exclusive(dev, id: "core");
604 if (IS_ERR(ptr: pcie_ep->core_reset))
605 return PTR_ERR(ptr: pcie_ep->core_reset);
606
607 pcie_ep->reset = devm_gpiod_get(dev, con_id: "reset", flags: GPIOD_IN);
608 if (IS_ERR(ptr: pcie_ep->reset))
609 return PTR_ERR(ptr: pcie_ep->reset);
610
611 pcie_ep->wake = devm_gpiod_get_optional(dev, con_id: "wake", flags: GPIOD_OUT_LOW);
612 if (IS_ERR(ptr: pcie_ep->wake))
613 return PTR_ERR(ptr: pcie_ep->wake);
614
615 pcie_ep->phy = devm_phy_optional_get(dev, string: "pciephy");
616 if (IS_ERR(ptr: pcie_ep->phy))
617 ret = PTR_ERR(ptr: pcie_ep->phy);
618
619 pcie_ep->icc_mem = devm_of_icc_get(dev, name: "pcie-mem");
620 if (IS_ERR(ptr: pcie_ep->icc_mem))
621 ret = PTR_ERR(ptr: pcie_ep->icc_mem);
622
623 return ret;
624}
625
626/* TODO: Notify clients about PCIe state change */
627static irqreturn_t qcom_pcie_ep_global_irq_thread(int irq, void *data)
628{
629 struct qcom_pcie_ep *pcie_ep = data;
630 struct dw_pcie *pci = &pcie_ep->pci;
631 struct device *dev = pci->dev;
632 u32 status = readl_relaxed(pcie_ep->parf + PARF_INT_ALL_STATUS);
633 u32 mask = readl_relaxed(pcie_ep->parf + PARF_INT_ALL_MASK);
634 u32 dstate, val;
635
636 writel_relaxed(status, pcie_ep->parf + PARF_INT_ALL_CLEAR);
637 status &= mask;
638
639 if (FIELD_GET(PARF_INT_ALL_LINK_DOWN, status)) {
640 dev_dbg(dev, "Received Linkdown event\n");
641 pcie_ep->link_status = QCOM_PCIE_EP_LINK_DOWN;
642 pci_epc_linkdown(epc: pci->ep.epc);
643 } else if (FIELD_GET(PARF_INT_ALL_BME, status)) {
644 dev_dbg(dev, "Received BME event. Link is enabled!\n");
645 pcie_ep->link_status = QCOM_PCIE_EP_LINK_ENABLED;
646 qcom_pcie_ep_icc_update(pcie_ep);
647 pci_epc_bme_notify(epc: pci->ep.epc);
648 } else if (FIELD_GET(PARF_INT_ALL_PM_TURNOFF, status)) {
649 dev_dbg(dev, "Received PM Turn-off event! Entering L23\n");
650 val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
651 val |= PARF_PM_CTRL_READY_ENTR_L23;
652 writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
653 } else if (FIELD_GET(PARF_INT_ALL_DSTATE_CHANGE, status)) {
654 dstate = dw_pcie_readl_dbi(pci, DBI_CON_STATUS) &
655 DBI_CON_STATUS_POWER_STATE_MASK;
656 dev_dbg(dev, "Received D%d state event\n", dstate);
657 if (dstate == 3) {
658 val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
659 val |= PARF_PM_CTRL_REQ_EXIT_L1;
660 writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
661 }
662 } else if (FIELD_GET(PARF_INT_ALL_LINK_UP, status)) {
663 dev_dbg(dev, "Received Linkup event. Enumeration complete!\n");
664 dw_pcie_ep_linkup(ep: &pci->ep);
665 pcie_ep->link_status = QCOM_PCIE_EP_LINK_UP;
666 } else {
667 dev_err(dev, "Received unknown event: %d\n", status);
668 }
669
670 return IRQ_HANDLED;
671}
672
673static irqreturn_t qcom_pcie_ep_perst_irq_thread(int irq, void *data)
674{
675 struct qcom_pcie_ep *pcie_ep = data;
676 struct dw_pcie *pci = &pcie_ep->pci;
677 struct device *dev = pci->dev;
678 u32 perst;
679
680 perst = gpiod_get_value(desc: pcie_ep->reset);
681 if (perst) {
682 dev_dbg(dev, "PERST asserted by host. Shutting down the PCIe link!\n");
683 qcom_pcie_perst_assert(pci);
684 } else {
685 dev_dbg(dev, "PERST de-asserted by host. Starting link training!\n");
686 qcom_pcie_perst_deassert(pci);
687 }
688
689 irq_set_irq_type(irq: gpiod_to_irq(desc: pcie_ep->reset),
690 type: (perst ? IRQF_TRIGGER_HIGH : IRQF_TRIGGER_LOW));
691
692 return IRQ_HANDLED;
693}
694
695static int qcom_pcie_ep_enable_irq_resources(struct platform_device *pdev,
696 struct qcom_pcie_ep *pcie_ep)
697{
698 int ret;
699
700 pcie_ep->global_irq = platform_get_irq_byname(pdev, "global");
701 if (pcie_ep->global_irq < 0)
702 return pcie_ep->global_irq;
703
704 ret = devm_request_threaded_irq(dev: &pdev->dev, irq: pcie_ep->global_irq, NULL,
705 thread_fn: qcom_pcie_ep_global_irq_thread,
706 IRQF_ONESHOT,
707 devname: "global_irq", dev_id: pcie_ep);
708 if (ret) {
709 dev_err(&pdev->dev, "Failed to request Global IRQ\n");
710 return ret;
711 }
712
713 pcie_ep->perst_irq = gpiod_to_irq(desc: pcie_ep->reset);
714 irq_set_status_flags(irq: pcie_ep->perst_irq, set: IRQ_NOAUTOEN);
715 ret = devm_request_threaded_irq(dev: &pdev->dev, irq: pcie_ep->perst_irq, NULL,
716 thread_fn: qcom_pcie_ep_perst_irq_thread,
717 IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
718 devname: "perst_irq", dev_id: pcie_ep);
719 if (ret) {
720 dev_err(&pdev->dev, "Failed to request PERST IRQ\n");
721 disable_irq(irq: pcie_ep->global_irq);
722 return ret;
723 }
724
725 return 0;
726}
727
728static int qcom_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
729 unsigned int type, u16 interrupt_num)
730{
731 struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
732
733 switch (type) {
734 case PCI_IRQ_INTX:
735 return dw_pcie_ep_raise_intx_irq(ep, func_no);
736 case PCI_IRQ_MSI:
737 return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
738 default:
739 dev_err(pci->dev, "Unknown IRQ type\n");
740 return -EINVAL;
741 }
742}
743
744static int qcom_pcie_ep_link_transition_count(struct seq_file *s, void *data)
745{
746 struct qcom_pcie_ep *pcie_ep = (struct qcom_pcie_ep *)
747 dev_get_drvdata(dev: s->private);
748
749 seq_printf(m: s, fmt: "L0s transition count: %u\n",
750 readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L0S));
751
752 seq_printf(m: s, fmt: "L1 transition count: %u\n",
753 readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L1));
754
755 seq_printf(m: s, fmt: "L1.1 transition count: %u\n",
756 readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1));
757
758 seq_printf(m: s, fmt: "L1.2 transition count: %u\n",
759 readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2));
760
761 seq_printf(m: s, fmt: "L2 transition count: %u\n",
762 readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L2));
763
764 return 0;
765}
766
767static void qcom_pcie_ep_init_debugfs(struct qcom_pcie_ep *pcie_ep)
768{
769 struct dw_pcie *pci = &pcie_ep->pci;
770
771 debugfs_create_devm_seqfile(dev: pci->dev, name: "link_transition_count", parent: pcie_ep->debugfs,
772 read_fn: qcom_pcie_ep_link_transition_count);
773}
774
775static const struct pci_epc_features qcom_pcie_epc_features = {
776 .linkup_notifier = true,
777 .core_init_notifier = true,
778 .msi_capable = true,
779 .msix_capable = false,
780 .align = SZ_4K,
781};
782
783static const struct pci_epc_features *
784qcom_pcie_epc_get_features(struct dw_pcie_ep *pci_ep)
785{
786 return &qcom_pcie_epc_features;
787}
788
789static void qcom_pcie_ep_init(struct dw_pcie_ep *ep)
790{
791 struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
792 enum pci_barno bar;
793
794 for (bar = BAR_0; bar <= BAR_5; bar++)
795 dw_pcie_ep_reset_bar(pci, bar);
796}
797
798static const struct dw_pcie_ep_ops pci_ep_ops = {
799 .init = qcom_pcie_ep_init,
800 .raise_irq = qcom_pcie_ep_raise_irq,
801 .get_features = qcom_pcie_epc_get_features,
802};
803
804static int qcom_pcie_ep_probe(struct platform_device *pdev)
805{
806 struct device *dev = &pdev->dev;
807 struct qcom_pcie_ep *pcie_ep;
808 char *name;
809 int ret;
810
811 pcie_ep = devm_kzalloc(dev, size: sizeof(*pcie_ep), GFP_KERNEL);
812 if (!pcie_ep)
813 return -ENOMEM;
814
815 pcie_ep->pci.dev = dev;
816 pcie_ep->pci.ops = &pci_ops;
817 pcie_ep->pci.ep.ops = &pci_ep_ops;
818 pcie_ep->pci.edma.nr_irqs = 1;
819 platform_set_drvdata(pdev, data: pcie_ep);
820
821 ret = qcom_pcie_ep_get_resources(pdev, pcie_ep);
822 if (ret)
823 return ret;
824
825 ret = qcom_pcie_enable_resources(pcie_ep);
826 if (ret) {
827 dev_err(dev, "Failed to enable resources: %d\n", ret);
828 return ret;
829 }
830
831 ret = dw_pcie_ep_init(ep: &pcie_ep->pci.ep);
832 if (ret) {
833 dev_err(dev, "Failed to initialize endpoint: %d\n", ret);
834 goto err_disable_resources;
835 }
836
837 ret = qcom_pcie_ep_enable_irq_resources(pdev, pcie_ep);
838 if (ret)
839 goto err_disable_resources;
840
841 name = devm_kasprintf(dev, GFP_KERNEL, fmt: "%pOFP", dev->of_node);
842 if (!name) {
843 ret = -ENOMEM;
844 goto err_disable_irqs;
845 }
846
847 pcie_ep->debugfs = debugfs_create_dir(name, NULL);
848 qcom_pcie_ep_init_debugfs(pcie_ep);
849
850 return 0;
851
852err_disable_irqs:
853 disable_irq(irq: pcie_ep->global_irq);
854 disable_irq(irq: pcie_ep->perst_irq);
855
856err_disable_resources:
857 qcom_pcie_disable_resources(pcie_ep);
858
859 return ret;
860}
861
862static void qcom_pcie_ep_remove(struct platform_device *pdev)
863{
864 struct qcom_pcie_ep *pcie_ep = platform_get_drvdata(pdev);
865
866 disable_irq(irq: pcie_ep->global_irq);
867 disable_irq(irq: pcie_ep->perst_irq);
868
869 debugfs_remove_recursive(dentry: pcie_ep->debugfs);
870
871 if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED)
872 return;
873
874 qcom_pcie_disable_resources(pcie_ep);
875}
876
877static const struct of_device_id qcom_pcie_ep_match[] = {
878 { .compatible = "qcom,sdx55-pcie-ep", },
879 { .compatible = "qcom,sm8450-pcie-ep", },
880 { }
881};
882MODULE_DEVICE_TABLE(of, qcom_pcie_ep_match);
883
884static struct platform_driver qcom_pcie_ep_driver = {
885 .probe = qcom_pcie_ep_probe,
886 .remove_new = qcom_pcie_ep_remove,
887 .driver = {
888 .name = "qcom-pcie-ep",
889 .of_match_table = qcom_pcie_ep_match,
890 },
891};
892builtin_platform_driver(qcom_pcie_ep_driver);
893
894MODULE_AUTHOR("Siddartha Mohanadoss <smohanad@codeaurora.org>");
895MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
896MODULE_DESCRIPTION("Qualcomm PCIe Endpoint controller driver");
897MODULE_LICENSE("GPL v2");
898

source code of linux/drivers/pci/controller/dwc/pcie-qcom-ep.c