1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * PCIe host controller driver for Mobiveil PCIe Host controller
4 *
5 * Copyright (c) 2018 Mobiveil Inc.
6 * Author: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
7 */
8
9 #include <linux/delay.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/irqchip/chained_irq.h>
14 #include <linux/irqdomain.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/msi.h>
18 #include <linux/of_address.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_platform.h>
21 #include <linux/of_pci.h>
22 #include <linux/pci.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25
26 #include "../pci.h"
27
28 /* register offsets and bit positions */
29
30 /*
31 * translation tables are grouped into windows, each window registers are
32 * grouped into blocks of 4 or 16 registers each
33 */
34 #define PAB_REG_BLOCK_SIZE 16
35 #define PAB_EXT_REG_BLOCK_SIZE 4
36
37 #define PAB_REG_ADDR(offset, win) \
38 (offset + (win * PAB_REG_BLOCK_SIZE))
39 #define PAB_EXT_REG_ADDR(offset, win) \
40 (offset + (win * PAB_EXT_REG_BLOCK_SIZE))
41
42 #define LTSSM_STATUS 0x0404
43 #define LTSSM_STATUS_L0_MASK 0x3f
44 #define LTSSM_STATUS_L0 0x2d
45
46 #define PAB_CTRL 0x0808
47 #define AMBA_PIO_ENABLE_SHIFT 0
48 #define PEX_PIO_ENABLE_SHIFT 1
49 #define PAGE_SEL_SHIFT 13
50 #define PAGE_SEL_MASK 0x3f
51 #define PAGE_LO_MASK 0x3ff
52 #define PAGE_SEL_OFFSET_SHIFT 10
53
54 #define PAB_AXI_PIO_CTRL 0x0840
55 #define APIO_EN_MASK 0xf
56
57 #define PAB_PEX_PIO_CTRL 0x08c0
58 #define PIO_ENABLE_SHIFT 0
59
60 #define PAB_INTP_AMBA_MISC_ENB 0x0b0c
61 #define PAB_INTP_AMBA_MISC_STAT 0x0b1c
62 #define PAB_INTP_INTX_MASK 0x01e0
63 #define PAB_INTP_MSI_MASK 0x8
64
65 #define PAB_AXI_AMAP_CTRL(win) PAB_REG_ADDR(0x0ba0, win)
66 #define WIN_ENABLE_SHIFT 0
67 #define WIN_TYPE_SHIFT 1
68 #define WIN_TYPE_MASK 0x3
69 #define WIN_SIZE_MASK 0xfffffc00
70
71 #define PAB_EXT_AXI_AMAP_SIZE(win) PAB_EXT_REG_ADDR(0xbaf0, win)
72
73 #define PAB_EXT_AXI_AMAP_AXI_WIN(win) PAB_EXT_REG_ADDR(0x80a0, win)
74 #define PAB_AXI_AMAP_AXI_WIN(win) PAB_REG_ADDR(0x0ba4, win)
75 #define AXI_WINDOW_ALIGN_MASK 3
76
77 #define PAB_AXI_AMAP_PEX_WIN_L(win) PAB_REG_ADDR(0x0ba8, win)
78 #define PAB_BUS_SHIFT 24
79 #define PAB_DEVICE_SHIFT 19
80 #define PAB_FUNCTION_SHIFT 16
81
82 #define PAB_AXI_AMAP_PEX_WIN_H(win) PAB_REG_ADDR(0x0bac, win)
83 #define PAB_INTP_AXI_PIO_CLASS 0x474
84
85 #define PAB_PEX_AMAP_CTRL(win) PAB_REG_ADDR(0x4ba0, win)
86 #define AMAP_CTRL_EN_SHIFT 0
87 #define AMAP_CTRL_TYPE_SHIFT 1
88 #define AMAP_CTRL_TYPE_MASK 3
89
90 #define PAB_EXT_PEX_AMAP_SIZEN(win) PAB_EXT_REG_ADDR(0xbef0, win)
91 #define PAB_EXT_PEX_AMAP_AXI_WIN(win) PAB_EXT_REG_ADDR(0xb4a0, win)
92 #define PAB_PEX_AMAP_AXI_WIN(win) PAB_REG_ADDR(0x4ba4, win)
93 #define PAB_PEX_AMAP_PEX_WIN_L(win) PAB_REG_ADDR(0x4ba8, win)
94 #define PAB_PEX_AMAP_PEX_WIN_H(win) PAB_REG_ADDR(0x4bac, win)
95
96 /* starting offset of INTX bits in status register */
97 #define PAB_INTX_START 5
98
99 /* supported number of MSI interrupts */
100 #define PCI_NUM_MSI 16
101
102 /* MSI registers */
103 #define MSI_BASE_LO_OFFSET 0x04
104 #define MSI_BASE_HI_OFFSET 0x08
105 #define MSI_SIZE_OFFSET 0x0c
106 #define MSI_ENABLE_OFFSET 0x14
107 #define MSI_STATUS_OFFSET 0x18
108 #define MSI_DATA_OFFSET 0x20
109 #define MSI_ADDR_L_OFFSET 0x24
110 #define MSI_ADDR_H_OFFSET 0x28
111
112 /* outbound and inbound window definitions */
113 #define WIN_NUM_0 0
114 #define WIN_NUM_1 1
115 #define CFG_WINDOW_TYPE 0
116 #define IO_WINDOW_TYPE 1
117 #define MEM_WINDOW_TYPE 2
118 #define IB_WIN_SIZE ((u64)256 * 1024 * 1024 * 1024)
119 #define MAX_PIO_WINDOWS 8
120
121 /* Parameters for the waiting for link up routine */
122 #define LINK_WAIT_MAX_RETRIES 10
123 #define LINK_WAIT_MIN 90000
124 #define LINK_WAIT_MAX 100000
125
126 #define PAGED_ADDR_BNDRY 0xc00
127 #define OFFSET_TO_PAGE_ADDR(off) \
128 ((off & PAGE_LO_MASK) | PAGED_ADDR_BNDRY)
129 #define OFFSET_TO_PAGE_IDX(off) \
130 ((off >> PAGE_SEL_OFFSET_SHIFT) & PAGE_SEL_MASK)
131
132 struct mobiveil_msi { /* MSI information */
133 struct mutex lock; /* protect bitmap variable */
134 struct irq_domain *msi_domain;
135 struct irq_domain *dev_domain;
136 phys_addr_t msi_pages_phys;
137 int num_of_vectors;
138 DECLARE_BITMAP(msi_irq_in_use, PCI_NUM_MSI);
139 };
140
141 struct mobiveil_pcie {
142 struct platform_device *pdev;
143 struct list_head resources;
144 void __iomem *config_axi_slave_base; /* endpoint config base */
145 void __iomem *csr_axi_slave_base; /* root port config base */
146 void __iomem *apb_csr_base; /* MSI register base */
147 phys_addr_t pcie_reg_base; /* Physical PCIe Controller Base */
148 struct irq_domain *intx_domain;
149 raw_spinlock_t intx_mask_lock;
150 int irq;
151 int apio_wins;
152 int ppio_wins;
153 int ob_wins_configured; /* configured outbound windows */
154 int ib_wins_configured; /* configured inbound windows */
155 struct resource *ob_io_res;
156 char root_bus_nr;
157 struct mobiveil_msi msi;
158 };
159
160 /*
161 * mobiveil_pcie_sel_page - routine to access paged register
162 *
163 * Registers whose address greater than PAGED_ADDR_BNDRY (0xc00) are paged,
164 * for this scheme to work extracted higher 6 bits of the offset will be
165 * written to pg_sel field of PAB_CTRL register and rest of the lower 10
166 * bits enabled with PAGED_ADDR_BNDRY are used as offset of the register.
167 */
mobiveil_pcie_sel_page(struct mobiveil_pcie * pcie,u8 pg_idx)168 static void mobiveil_pcie_sel_page(struct mobiveil_pcie *pcie, u8 pg_idx)
169 {
170 u32 val;
171
172 val = readl(pcie->csr_axi_slave_base + PAB_CTRL);
173 val &= ~(PAGE_SEL_MASK << PAGE_SEL_SHIFT);
174 val |= (pg_idx & PAGE_SEL_MASK) << PAGE_SEL_SHIFT;
175
176 writel(val, pcie->csr_axi_slave_base + PAB_CTRL);
177 }
178
mobiveil_pcie_comp_addr(struct mobiveil_pcie * pcie,u32 off)179 static void *mobiveil_pcie_comp_addr(struct mobiveil_pcie *pcie, u32 off)
180 {
181 if (off < PAGED_ADDR_BNDRY) {
182 /* For directly accessed registers, clear the pg_sel field */
183 mobiveil_pcie_sel_page(pcie, 0);
184 return pcie->csr_axi_slave_base + off;
185 }
186
187 mobiveil_pcie_sel_page(pcie, OFFSET_TO_PAGE_IDX(off));
188 return pcie->csr_axi_slave_base + OFFSET_TO_PAGE_ADDR(off);
189 }
190
mobiveil_pcie_read(void __iomem * addr,int size,u32 * val)191 static int mobiveil_pcie_read(void __iomem *addr, int size, u32 *val)
192 {
193 if ((uintptr_t)addr & (size - 1)) {
194 *val = 0;
195 return PCIBIOS_BAD_REGISTER_NUMBER;
196 }
197
198 switch (size) {
199 case 4:
200 *val = readl(addr);
201 break;
202 case 2:
203 *val = readw(addr);
204 break;
205 case 1:
206 *val = readb(addr);
207 break;
208 default:
209 *val = 0;
210 return PCIBIOS_BAD_REGISTER_NUMBER;
211 }
212
213 return PCIBIOS_SUCCESSFUL;
214 }
215
mobiveil_pcie_write(void __iomem * addr,int size,u32 val)216 static int mobiveil_pcie_write(void __iomem *addr, int size, u32 val)
217 {
218 if ((uintptr_t)addr & (size - 1))
219 return PCIBIOS_BAD_REGISTER_NUMBER;
220
221 switch (size) {
222 case 4:
223 writel(val, addr);
224 break;
225 case 2:
226 writew(val, addr);
227 break;
228 case 1:
229 writeb(val, addr);
230 break;
231 default:
232 return PCIBIOS_BAD_REGISTER_NUMBER;
233 }
234
235 return PCIBIOS_SUCCESSFUL;
236 }
237
csr_read(struct mobiveil_pcie * pcie,u32 off,size_t size)238 static u32 csr_read(struct mobiveil_pcie *pcie, u32 off, size_t size)
239 {
240 void *addr;
241 u32 val;
242 int ret;
243
244 addr = mobiveil_pcie_comp_addr(pcie, off);
245
246 ret = mobiveil_pcie_read(addr, size, &val);
247 if (ret)
248 dev_err(&pcie->pdev->dev, "read CSR address failed\n");
249
250 return val;
251 }
252
csr_write(struct mobiveil_pcie * pcie,u32 val,u32 off,size_t size)253 static void csr_write(struct mobiveil_pcie *pcie, u32 val, u32 off, size_t size)
254 {
255 void *addr;
256 int ret;
257
258 addr = mobiveil_pcie_comp_addr(pcie, off);
259
260 ret = mobiveil_pcie_write(addr, size, val);
261 if (ret)
262 dev_err(&pcie->pdev->dev, "write CSR address failed\n");
263 }
264
csr_readl(struct mobiveil_pcie * pcie,u32 off)265 static u32 csr_readl(struct mobiveil_pcie *pcie, u32 off)
266 {
267 return csr_read(pcie, off, 0x4);
268 }
269
csr_writel(struct mobiveil_pcie * pcie,u32 val,u32 off)270 static void csr_writel(struct mobiveil_pcie *pcie, u32 val, u32 off)
271 {
272 csr_write(pcie, val, off, 0x4);
273 }
274
mobiveil_pcie_link_up(struct mobiveil_pcie * pcie)275 static bool mobiveil_pcie_link_up(struct mobiveil_pcie *pcie)
276 {
277 return (csr_readl(pcie, LTSSM_STATUS) &
278 LTSSM_STATUS_L0_MASK) == LTSSM_STATUS_L0;
279 }
280
mobiveil_pcie_valid_device(struct pci_bus * bus,unsigned int devfn)281 static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
282 {
283 struct mobiveil_pcie *pcie = bus->sysdata;
284
285 /* Only one device down on each root port */
286 if ((bus->number == pcie->root_bus_nr) && (devfn > 0))
287 return false;
288
289 /*
290 * Do not read more than one device on the bus directly
291 * attached to RC
292 */
293 if ((bus->primary == pcie->root_bus_nr) && (PCI_SLOT(devfn) > 0))
294 return false;
295
296 return true;
297 }
298
299 /*
300 * mobiveil_pcie_map_bus - routine to get the configuration base of either
301 * root port or endpoint
302 */
mobiveil_pcie_map_bus(struct pci_bus * bus,unsigned int devfn,int where)303 static void __iomem *mobiveil_pcie_map_bus(struct pci_bus *bus,
304 unsigned int devfn, int where)
305 {
306 struct mobiveil_pcie *pcie = bus->sysdata;
307 u32 value;
308
309 if (!mobiveil_pcie_valid_device(bus, devfn))
310 return NULL;
311
312 /* RC config access */
313 if (bus->number == pcie->root_bus_nr)
314 return pcie->csr_axi_slave_base + where;
315
316 /*
317 * EP config access (in Config/APIO space)
318 * Program PEX Address base (31..16 bits) with appropriate value
319 * (BDF) in PAB_AXI_AMAP_PEX_WIN_L0 Register.
320 * Relies on pci_lock serialization
321 */
322 value = bus->number << PAB_BUS_SHIFT |
323 PCI_SLOT(devfn) << PAB_DEVICE_SHIFT |
324 PCI_FUNC(devfn) << PAB_FUNCTION_SHIFT;
325
326 csr_writel(pcie, value, PAB_AXI_AMAP_PEX_WIN_L(WIN_NUM_0));
327
328 return pcie->config_axi_slave_base + where;
329 }
330
331 static struct pci_ops mobiveil_pcie_ops = {
332 .map_bus = mobiveil_pcie_map_bus,
333 .read = pci_generic_config_read,
334 .write = pci_generic_config_write,
335 };
336
mobiveil_pcie_isr(struct irq_desc * desc)337 static void mobiveil_pcie_isr(struct irq_desc *desc)
338 {
339 struct irq_chip *chip = irq_desc_get_chip(desc);
340 struct mobiveil_pcie *pcie = irq_desc_get_handler_data(desc);
341 struct device *dev = &pcie->pdev->dev;
342 struct mobiveil_msi *msi = &pcie->msi;
343 u32 msi_data, msi_addr_lo, msi_addr_hi;
344 u32 intr_status, msi_status;
345 unsigned long shifted_status;
346 u32 bit, virq, val, mask;
347
348 /*
349 * The core provides a single interrupt for both INTx/MSI messages.
350 * So we'll read both INTx and MSI status
351 */
352
353 chained_irq_enter(chip, desc);
354
355 /* read INTx status */
356 val = csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
357 mask = csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
358 intr_status = val & mask;
359
360 /* Handle INTx */
361 if (intr_status & PAB_INTP_INTX_MASK) {
362 shifted_status = csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
363 shifted_status &= PAB_INTP_INTX_MASK;
364 shifted_status >>= PAB_INTX_START;
365 do {
366 for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
367 virq = irq_find_mapping(pcie->intx_domain,
368 bit + 1);
369 if (virq)
370 generic_handle_irq(virq);
371 else
372 dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
373 bit);
374
375 /* clear interrupt handled */
376 csr_writel(pcie, 1 << (PAB_INTX_START + bit),
377 PAB_INTP_AMBA_MISC_STAT);
378 }
379
380 shifted_status = csr_readl(pcie,
381 PAB_INTP_AMBA_MISC_STAT);
382 shifted_status &= PAB_INTP_INTX_MASK;
383 shifted_status >>= PAB_INTX_START;
384 } while (shifted_status != 0);
385 }
386
387 /* read extra MSI status register */
388 msi_status = readl_relaxed(pcie->apb_csr_base + MSI_STATUS_OFFSET);
389
390 /* handle MSI interrupts */
391 while (msi_status & 1) {
392 msi_data = readl_relaxed(pcie->apb_csr_base + MSI_DATA_OFFSET);
393
394 /*
395 * MSI_STATUS_OFFSET register gets updated to zero
396 * once we pop not only the MSI data but also address
397 * from MSI hardware FIFO. So keeping these following
398 * two dummy reads.
399 */
400 msi_addr_lo = readl_relaxed(pcie->apb_csr_base +
401 MSI_ADDR_L_OFFSET);
402 msi_addr_hi = readl_relaxed(pcie->apb_csr_base +
403 MSI_ADDR_H_OFFSET);
404 dev_dbg(dev, "MSI registers, data: %08x, addr: %08x:%08x\n",
405 msi_data, msi_addr_hi, msi_addr_lo);
406
407 virq = irq_find_mapping(msi->dev_domain, msi_data);
408 if (virq)
409 generic_handle_irq(virq);
410
411 msi_status = readl_relaxed(pcie->apb_csr_base +
412 MSI_STATUS_OFFSET);
413 }
414
415 /* Clear the interrupt status */
416 csr_writel(pcie, intr_status, PAB_INTP_AMBA_MISC_STAT);
417 chained_irq_exit(chip, desc);
418 }
419
mobiveil_pcie_parse_dt(struct mobiveil_pcie * pcie)420 static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie)
421 {
422 struct device *dev = &pcie->pdev->dev;
423 struct platform_device *pdev = pcie->pdev;
424 struct device_node *node = dev->of_node;
425 struct resource *res;
426
427 /* map config resource */
428 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
429 "config_axi_slave");
430 pcie->config_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
431 if (IS_ERR(pcie->config_axi_slave_base))
432 return PTR_ERR(pcie->config_axi_slave_base);
433 pcie->ob_io_res = res;
434
435 /* map csr resource */
436 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
437 "csr_axi_slave");
438 pcie->csr_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
439 if (IS_ERR(pcie->csr_axi_slave_base))
440 return PTR_ERR(pcie->csr_axi_slave_base);
441 pcie->pcie_reg_base = res->start;
442
443 /* map MSI config resource */
444 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "apb_csr");
445 pcie->apb_csr_base = devm_pci_remap_cfg_resource(dev, res);
446 if (IS_ERR(pcie->apb_csr_base))
447 return PTR_ERR(pcie->apb_csr_base);
448
449 /* read the number of windows requested */
450 if (of_property_read_u32(node, "apio-wins", &pcie->apio_wins))
451 pcie->apio_wins = MAX_PIO_WINDOWS;
452
453 if (of_property_read_u32(node, "ppio-wins", &pcie->ppio_wins))
454 pcie->ppio_wins = MAX_PIO_WINDOWS;
455
456 pcie->irq = platform_get_irq(pdev, 0);
457 if (pcie->irq <= 0) {
458 dev_err(dev, "failed to map IRQ: %d\n", pcie->irq);
459 return -ENODEV;
460 }
461
462 return 0;
463 }
464
program_ib_windows(struct mobiveil_pcie * pcie,int win_num,u64 cpu_addr,u64 pci_addr,u32 type,u64 size)465 static void program_ib_windows(struct mobiveil_pcie *pcie, int win_num,
466 u64 cpu_addr, u64 pci_addr, u32 type, u64 size)
467 {
468 u32 value;
469 u64 size64 = ~(size - 1);
470
471 if (win_num >= pcie->ppio_wins) {
472 dev_err(&pcie->pdev->dev,
473 "ERROR: max inbound windows reached !\n");
474 return;
475 }
476
477 value = csr_readl(pcie, PAB_PEX_AMAP_CTRL(win_num));
478 value &= ~(AMAP_CTRL_TYPE_MASK << AMAP_CTRL_TYPE_SHIFT | WIN_SIZE_MASK);
479 value |= type << AMAP_CTRL_TYPE_SHIFT | 1 << AMAP_CTRL_EN_SHIFT |
480 (lower_32_bits(size64) & WIN_SIZE_MASK);
481 csr_writel(pcie, value, PAB_PEX_AMAP_CTRL(win_num));
482
483 csr_writel(pcie, upper_32_bits(size64),
484 PAB_EXT_PEX_AMAP_SIZEN(win_num));
485
486 csr_writel(pcie, lower_32_bits(cpu_addr),
487 PAB_PEX_AMAP_AXI_WIN(win_num));
488 csr_writel(pcie, upper_32_bits(cpu_addr),
489 PAB_EXT_PEX_AMAP_AXI_WIN(win_num));
490
491 csr_writel(pcie, lower_32_bits(pci_addr),
492 PAB_PEX_AMAP_PEX_WIN_L(win_num));
493 csr_writel(pcie, upper_32_bits(pci_addr),
494 PAB_PEX_AMAP_PEX_WIN_H(win_num));
495
496 pcie->ib_wins_configured++;
497 }
498
499 /*
500 * routine to program the outbound windows
501 */
program_ob_windows(struct mobiveil_pcie * pcie,int win_num,u64 cpu_addr,u64 pci_addr,u32 type,u64 size)502 static void program_ob_windows(struct mobiveil_pcie *pcie, int win_num,
503 u64 cpu_addr, u64 pci_addr, u32 type, u64 size)
504 {
505 u32 value;
506 u64 size64 = ~(size - 1);
507
508 if (win_num >= pcie->apio_wins) {
509 dev_err(&pcie->pdev->dev,
510 "ERROR: max outbound windows reached !\n");
511 return;
512 }
513
514 /*
515 * program Enable Bit to 1, Type Bit to (00) base 2, AXI Window Size Bit
516 * to 4 KB in PAB_AXI_AMAP_CTRL register
517 */
518 value = csr_readl(pcie, PAB_AXI_AMAP_CTRL(win_num));
519 value &= ~(WIN_TYPE_MASK << WIN_TYPE_SHIFT | WIN_SIZE_MASK);
520 value |= 1 << WIN_ENABLE_SHIFT | type << WIN_TYPE_SHIFT |
521 (lower_32_bits(size64) & WIN_SIZE_MASK);
522 csr_writel(pcie, value, PAB_AXI_AMAP_CTRL(win_num));
523
524 csr_writel(pcie, upper_32_bits(size64), PAB_EXT_AXI_AMAP_SIZE(win_num));
525
526 /*
527 * program AXI window base with appropriate value in
528 * PAB_AXI_AMAP_AXI_WIN0 register
529 */
530 csr_writel(pcie, lower_32_bits(cpu_addr) & (~AXI_WINDOW_ALIGN_MASK),
531 PAB_AXI_AMAP_AXI_WIN(win_num));
532 csr_writel(pcie, upper_32_bits(cpu_addr),
533 PAB_EXT_AXI_AMAP_AXI_WIN(win_num));
534
535 csr_writel(pcie, lower_32_bits(pci_addr),
536 PAB_AXI_AMAP_PEX_WIN_L(win_num));
537 csr_writel(pcie, upper_32_bits(pci_addr),
538 PAB_AXI_AMAP_PEX_WIN_H(win_num));
539
540 pcie->ob_wins_configured++;
541 }
542
mobiveil_bringup_link(struct mobiveil_pcie * pcie)543 static int mobiveil_bringup_link(struct mobiveil_pcie *pcie)
544 {
545 int retries;
546
547 /* check if the link is up or not */
548 for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
549 if (mobiveil_pcie_link_up(pcie))
550 return 0;
551
552 usleep_range(LINK_WAIT_MIN, LINK_WAIT_MAX);
553 }
554
555 dev_err(&pcie->pdev->dev, "link never came up\n");
556
557 return -ETIMEDOUT;
558 }
559
mobiveil_pcie_enable_msi(struct mobiveil_pcie * pcie)560 static void mobiveil_pcie_enable_msi(struct mobiveil_pcie *pcie)
561 {
562 phys_addr_t msg_addr = pcie->pcie_reg_base;
563 struct mobiveil_msi *msi = &pcie->msi;
564
565 pcie->msi.num_of_vectors = PCI_NUM_MSI;
566 msi->msi_pages_phys = (phys_addr_t)msg_addr;
567
568 writel_relaxed(lower_32_bits(msg_addr),
569 pcie->apb_csr_base + MSI_BASE_LO_OFFSET);
570 writel_relaxed(upper_32_bits(msg_addr),
571 pcie->apb_csr_base + MSI_BASE_HI_OFFSET);
572 writel_relaxed(4096, pcie->apb_csr_base + MSI_SIZE_OFFSET);
573 writel_relaxed(1, pcie->apb_csr_base + MSI_ENABLE_OFFSET);
574 }
575
mobiveil_host_init(struct mobiveil_pcie * pcie)576 static int mobiveil_host_init(struct mobiveil_pcie *pcie)
577 {
578 u32 value, pab_ctrl, type;
579 struct resource_entry *win;
580
581 /* setup bus numbers */
582 value = csr_readl(pcie, PCI_PRIMARY_BUS);
583 value &= 0xff000000;
584 value |= 0x00ff0100;
585 csr_writel(pcie, value, PCI_PRIMARY_BUS);
586
587 /*
588 * program Bus Master Enable Bit in Command Register in PAB Config
589 * Space
590 */
591 value = csr_readl(pcie, PCI_COMMAND);
592 value |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
593 csr_writel(pcie, value, PCI_COMMAND);
594
595 /*
596 * program PIO Enable Bit to 1 (and PEX PIO Enable to 1) in PAB_CTRL
597 * register
598 */
599 pab_ctrl = csr_readl(pcie, PAB_CTRL);
600 pab_ctrl |= (1 << AMBA_PIO_ENABLE_SHIFT) | (1 << PEX_PIO_ENABLE_SHIFT);
601 csr_writel(pcie, pab_ctrl, PAB_CTRL);
602
603 csr_writel(pcie, (PAB_INTP_INTX_MASK | PAB_INTP_MSI_MASK),
604 PAB_INTP_AMBA_MISC_ENB);
605
606 /*
607 * program PIO Enable Bit to 1 and Config Window Enable Bit to 1 in
608 * PAB_AXI_PIO_CTRL Register
609 */
610 value = csr_readl(pcie, PAB_AXI_PIO_CTRL);
611 value |= APIO_EN_MASK;
612 csr_writel(pcie, value, PAB_AXI_PIO_CTRL);
613
614 /* Enable PCIe PIO master */
615 value = csr_readl(pcie, PAB_PEX_PIO_CTRL);
616 value |= 1 << PIO_ENABLE_SHIFT;
617 csr_writel(pcie, value, PAB_PEX_PIO_CTRL);
618
619 /*
620 * we'll program one outbound window for config reads and
621 * another default inbound window for all the upstream traffic
622 * rest of the outbound windows will be configured according to
623 * the "ranges" field defined in device tree
624 */
625
626 /* config outbound translation window */
627 program_ob_windows(pcie, WIN_NUM_0, pcie->ob_io_res->start, 0,
628 CFG_WINDOW_TYPE, resource_size(pcie->ob_io_res));
629
630 /* memory inbound translation window */
631 program_ib_windows(pcie, WIN_NUM_0, 0, 0, MEM_WINDOW_TYPE, IB_WIN_SIZE);
632
633 /* Get the I/O and memory ranges from DT */
634 resource_list_for_each_entry(win, &pcie->resources) {
635 if (resource_type(win->res) == IORESOURCE_MEM)
636 type = MEM_WINDOW_TYPE;
637 else if (resource_type(win->res) == IORESOURCE_IO)
638 type = IO_WINDOW_TYPE;
639 else
640 continue;
641
642 /* configure outbound translation window */
643 program_ob_windows(pcie, pcie->ob_wins_configured,
644 win->res->start,
645 win->res->start - win->offset,
646 type, resource_size(win->res));
647 }
648
649 /* fixup for PCIe class register */
650 value = csr_readl(pcie, PAB_INTP_AXI_PIO_CLASS);
651 value &= 0xff;
652 value |= (PCI_CLASS_BRIDGE_PCI << 16);
653 csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS);
654
655 /* setup MSI hardware registers */
656 mobiveil_pcie_enable_msi(pcie);
657
658 return 0;
659 }
660
mobiveil_mask_intx_irq(struct irq_data * data)661 static void mobiveil_mask_intx_irq(struct irq_data *data)
662 {
663 struct irq_desc *desc = irq_to_desc(data->irq);
664 struct mobiveil_pcie *pcie;
665 unsigned long flags;
666 u32 mask, shifted_val;
667
668 pcie = irq_desc_get_chip_data(desc);
669 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
670 raw_spin_lock_irqsave(&pcie->intx_mask_lock, flags);
671 shifted_val = csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
672 shifted_val &= ~mask;
673 csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
674 raw_spin_unlock_irqrestore(&pcie->intx_mask_lock, flags);
675 }
676
mobiveil_unmask_intx_irq(struct irq_data * data)677 static void mobiveil_unmask_intx_irq(struct irq_data *data)
678 {
679 struct irq_desc *desc = irq_to_desc(data->irq);
680 struct mobiveil_pcie *pcie;
681 unsigned long flags;
682 u32 shifted_val, mask;
683
684 pcie = irq_desc_get_chip_data(desc);
685 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
686 raw_spin_lock_irqsave(&pcie->intx_mask_lock, flags);
687 shifted_val = csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
688 shifted_val |= mask;
689 csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
690 raw_spin_unlock_irqrestore(&pcie->intx_mask_lock, flags);
691 }
692
693 static struct irq_chip intx_irq_chip = {
694 .name = "mobiveil_pcie:intx",
695 .irq_enable = mobiveil_unmask_intx_irq,
696 .irq_disable = mobiveil_mask_intx_irq,
697 .irq_mask = mobiveil_mask_intx_irq,
698 .irq_unmask = mobiveil_unmask_intx_irq,
699 };
700
701 /* routine to setup the INTx related data */
mobiveil_pcie_intx_map(struct irq_domain * domain,unsigned int irq,irq_hw_number_t hwirq)702 static int mobiveil_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
703 irq_hw_number_t hwirq)
704 {
705 irq_set_chip_and_handler(irq, &intx_irq_chip, handle_level_irq);
706 irq_set_chip_data(irq, domain->host_data);
707
708 return 0;
709 }
710
711 /* INTx domain operations structure */
712 static const struct irq_domain_ops intx_domain_ops = {
713 .map = mobiveil_pcie_intx_map,
714 };
715
716 static struct irq_chip mobiveil_msi_irq_chip = {
717 .name = "Mobiveil PCIe MSI",
718 .irq_mask = pci_msi_mask_irq,
719 .irq_unmask = pci_msi_unmask_irq,
720 };
721
722 static struct msi_domain_info mobiveil_msi_domain_info = {
723 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
724 MSI_FLAG_PCI_MSIX),
725 .chip = &mobiveil_msi_irq_chip,
726 };
727
mobiveil_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)728 static void mobiveil_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
729 {
730 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
731 phys_addr_t addr = pcie->pcie_reg_base + (data->hwirq * sizeof(int));
732
733 msg->address_lo = lower_32_bits(addr);
734 msg->address_hi = upper_32_bits(addr);
735 msg->data = data->hwirq;
736
737 dev_dbg(&pcie->pdev->dev, "msi#%d address_hi %#x address_lo %#x\n",
738 (int)data->hwirq, msg->address_hi, msg->address_lo);
739 }
740
mobiveil_msi_set_affinity(struct irq_data * irq_data,const struct cpumask * mask,bool force)741 static int mobiveil_msi_set_affinity(struct irq_data *irq_data,
742 const struct cpumask *mask, bool force)
743 {
744 return -EINVAL;
745 }
746
747 static struct irq_chip mobiveil_msi_bottom_irq_chip = {
748 .name = "Mobiveil MSI",
749 .irq_compose_msi_msg = mobiveil_compose_msi_msg,
750 .irq_set_affinity = mobiveil_msi_set_affinity,
751 };
752
mobiveil_irq_msi_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * args)753 static int mobiveil_irq_msi_domain_alloc(struct irq_domain *domain,
754 unsigned int virq,
755 unsigned int nr_irqs, void *args)
756 {
757 struct mobiveil_pcie *pcie = domain->host_data;
758 struct mobiveil_msi *msi = &pcie->msi;
759 unsigned long bit;
760
761 WARN_ON(nr_irqs != 1);
762 mutex_lock(&msi->lock);
763
764 bit = find_first_zero_bit(msi->msi_irq_in_use, msi->num_of_vectors);
765 if (bit >= msi->num_of_vectors) {
766 mutex_unlock(&msi->lock);
767 return -ENOSPC;
768 }
769
770 set_bit(bit, msi->msi_irq_in_use);
771
772 mutex_unlock(&msi->lock);
773
774 irq_domain_set_info(domain, virq, bit, &mobiveil_msi_bottom_irq_chip,
775 domain->host_data, handle_level_irq, NULL, NULL);
776 return 0;
777 }
778
mobiveil_irq_msi_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)779 static void mobiveil_irq_msi_domain_free(struct irq_domain *domain,
780 unsigned int virq,
781 unsigned int nr_irqs)
782 {
783 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
784 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(d);
785 struct mobiveil_msi *msi = &pcie->msi;
786
787 mutex_lock(&msi->lock);
788
789 if (!test_bit(d->hwirq, msi->msi_irq_in_use))
790 dev_err(&pcie->pdev->dev, "trying to free unused MSI#%lu\n",
791 d->hwirq);
792 else
793 __clear_bit(d->hwirq, msi->msi_irq_in_use);
794
795 mutex_unlock(&msi->lock);
796 }
797 static const struct irq_domain_ops msi_domain_ops = {
798 .alloc = mobiveil_irq_msi_domain_alloc,
799 .free = mobiveil_irq_msi_domain_free,
800 };
801
mobiveil_allocate_msi_domains(struct mobiveil_pcie * pcie)802 static int mobiveil_allocate_msi_domains(struct mobiveil_pcie *pcie)
803 {
804 struct device *dev = &pcie->pdev->dev;
805 struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
806 struct mobiveil_msi *msi = &pcie->msi;
807
808 mutex_init(&pcie->msi.lock);
809 msi->dev_domain = irq_domain_add_linear(NULL, msi->num_of_vectors,
810 &msi_domain_ops, pcie);
811 if (!msi->dev_domain) {
812 dev_err(dev, "failed to create IRQ domain\n");
813 return -ENOMEM;
814 }
815
816 msi->msi_domain = pci_msi_create_irq_domain(fwnode,
817 &mobiveil_msi_domain_info,
818 msi->dev_domain);
819 if (!msi->msi_domain) {
820 dev_err(dev, "failed to create MSI domain\n");
821 irq_domain_remove(msi->dev_domain);
822 return -ENOMEM;
823 }
824
825 return 0;
826 }
827
mobiveil_pcie_init_irq_domain(struct mobiveil_pcie * pcie)828 static int mobiveil_pcie_init_irq_domain(struct mobiveil_pcie *pcie)
829 {
830 struct device *dev = &pcie->pdev->dev;
831 struct device_node *node = dev->of_node;
832 int ret;
833
834 /* setup INTx */
835 pcie->intx_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
836 &intx_domain_ops, pcie);
837
838 if (!pcie->intx_domain) {
839 dev_err(dev, "Failed to get a INTx IRQ domain\n");
840 return -ENOMEM;
841 }
842
843 raw_spin_lock_init(&pcie->intx_mask_lock);
844
845 /* setup MSI */
846 ret = mobiveil_allocate_msi_domains(pcie);
847 if (ret)
848 return ret;
849
850 return 0;
851 }
852
mobiveil_pcie_probe(struct platform_device * pdev)853 static int mobiveil_pcie_probe(struct platform_device *pdev)
854 {
855 struct mobiveil_pcie *pcie;
856 struct pci_bus *bus;
857 struct pci_bus *child;
858 struct pci_host_bridge *bridge;
859 struct device *dev = &pdev->dev;
860 resource_size_t iobase;
861 int ret;
862
863 /* allocate the PCIe port */
864 bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
865 if (!bridge)
866 return -ENOMEM;
867
868 pcie = pci_host_bridge_priv(bridge);
869
870 pcie->pdev = pdev;
871
872 ret = mobiveil_pcie_parse_dt(pcie);
873 if (ret) {
874 dev_err(dev, "Parsing DT failed, ret: %x\n", ret);
875 return ret;
876 }
877
878 INIT_LIST_HEAD(&pcie->resources);
879
880 /* parse the host bridge base addresses from the device tree file */
881 ret = devm_of_pci_get_host_bridge_resources(dev, 0, 0xff,
882 &pcie->resources, &iobase);
883 if (ret) {
884 dev_err(dev, "Getting bridge resources failed\n");
885 return ret;
886 }
887
888 /*
889 * configure all inbound and outbound windows and prepare the RC for
890 * config access
891 */
892 ret = mobiveil_host_init(pcie);
893 if (ret) {
894 dev_err(dev, "Failed to initialize host\n");
895 goto error;
896 }
897
898 /* initialize the IRQ domains */
899 ret = mobiveil_pcie_init_irq_domain(pcie);
900 if (ret) {
901 dev_err(dev, "Failed creating IRQ Domain\n");
902 goto error;
903 }
904
905 irq_set_chained_handler_and_data(pcie->irq, mobiveil_pcie_isr, pcie);
906
907 ret = devm_request_pci_bus_resources(dev, &pcie->resources);
908 if (ret)
909 goto error;
910
911 /* Initialize bridge */
912 list_splice_init(&pcie->resources, &bridge->windows);
913 bridge->dev.parent = dev;
914 bridge->sysdata = pcie;
915 bridge->busnr = pcie->root_bus_nr;
916 bridge->ops = &mobiveil_pcie_ops;
917 bridge->map_irq = of_irq_parse_and_map_pci;
918 bridge->swizzle_irq = pci_common_swizzle;
919
920 ret = mobiveil_bringup_link(pcie);
921 if (ret) {
922 dev_info(dev, "link bring-up failed\n");
923 goto error;
924 }
925
926 /* setup the kernel resources for the newly added PCIe root bus */
927 ret = pci_scan_root_bus_bridge(bridge);
928 if (ret)
929 goto error;
930
931 bus = bridge->bus;
932
933 pci_assign_unassigned_bus_resources(bus);
934 list_for_each_entry(child, &bus->children, node)
935 pcie_bus_configure_settings(child);
936 pci_bus_add_devices(bus);
937
938 return 0;
939 error:
940 pci_free_resource_list(&pcie->resources);
941 return ret;
942 }
943
944 static const struct of_device_id mobiveil_pcie_of_match[] = {
945 {.compatible = "mbvl,gpex40-pcie",},
946 {},
947 };
948
949 MODULE_DEVICE_TABLE(of, mobiveil_pcie_of_match);
950
951 static struct platform_driver mobiveil_pcie_driver = {
952 .probe = mobiveil_pcie_probe,
953 .driver = {
954 .name = "mobiveil-pcie",
955 .of_match_table = mobiveil_pcie_of_match,
956 .suppress_bind_attrs = true,
957 },
958 };
959
960 builtin_platform_driver(mobiveil_pcie_driver);
961
962 MODULE_LICENSE("GPL v2");
963 MODULE_DESCRIPTION("Mobiveil PCIe host controller driver");
964 MODULE_AUTHOR("Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>");
965
