1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCIe driver for Renesas R-Car SoCs
4 *  Copyright (C) 2014-2020 Renesas Electronics Europe Ltd
5 *
6 * Author: Phil Edworthy <phil.edworthy@renesas.com>
7 */
8
9#include <linux/delay.h>
10#include <linux/pci.h>
11
12#include "pcie-rcar.h"
13
14void rcar_pci_write_reg(struct rcar_pcie *pcie, u32 val, unsigned int reg)
15{
16	writel(val, pcie->base + reg);
17}
18
19u32 rcar_pci_read_reg(struct rcar_pcie *pcie, unsigned int reg)
20{
21	return readl(pcie->base + reg);
22}
23
24void rcar_rmw32(struct rcar_pcie *pcie, int where, u32 mask, u32 data)
25{
26	unsigned int shift = BITS_PER_BYTE * (where & 3);
27	u32 val = rcar_pci_read_reg(pcie, where & ~3);
28
29	val &= ~(mask << shift);
30	val |= data << shift;
31	rcar_pci_write_reg(pcie, val, where & ~3);
32}
33
34int rcar_pcie_wait_for_phyrdy(struct rcar_pcie *pcie)
35{
36	unsigned int timeout = 10;
37
38	while (timeout--) {
39		if (rcar_pci_read_reg(pcie, PCIEPHYSR) & PHYRDY)
40			return 0;
41
42		msleep(5);
43	}
44
45	return -ETIMEDOUT;
46}
47
48int rcar_pcie_wait_for_dl(struct rcar_pcie *pcie)
49{
50	unsigned int timeout = 10000;
51
52	while (timeout--) {
53		if ((rcar_pci_read_reg(pcie, PCIETSTR) & DATA_LINK_ACTIVE))
54			return 0;
55
56		udelay(5);
57		cpu_relax();
58	}
59
60	return -ETIMEDOUT;
61}
62
63void rcar_pcie_set_outbound(struct rcar_pcie *pcie, int win,
64			    struct resource_entry *window)
65{
66	/* Setup PCIe address space mappings for each resource */
67	struct resource *res = window->res;
68	resource_size_t res_start;
69	resource_size_t size;
70	u32 mask;
71
72	rcar_pci_write_reg(pcie, 0x00000000, PCIEPTCTLR(win));
73
74	/*
75	 * The PAMR mask is calculated in units of 128Bytes, which
76	 * keeps things pretty simple.
77	 */
78	size = resource_size(res);
79	if (size > 128)
80		mask = (roundup_pow_of_two(size) / SZ_128) - 1;
81	else
82		mask = 0x0;
83	rcar_pci_write_reg(pcie, mask << 7, PCIEPAMR(win));
84
85	if (res->flags & IORESOURCE_IO)
86		res_start = pci_pio_to_address(res->start) - window->offset;
87	else
88		res_start = res->start - window->offset;
89
90	rcar_pci_write_reg(pcie, upper_32_bits(res_start), PCIEPAUR(win));
91	rcar_pci_write_reg(pcie, lower_32_bits(res_start) & ~0x7F,
92			   PCIEPALR(win));
93
94	/* First resource is for IO */
95	mask = PAR_ENABLE;
96	if (res->flags & IORESOURCE_IO)
97		mask |= IO_SPACE;
98
99	rcar_pci_write_reg(pcie, mask, PCIEPTCTLR(win));
100}
101
102void rcar_pcie_set_inbound(struct rcar_pcie *pcie, u64 cpu_addr,
103			   u64 pci_addr, u64 flags, int idx, bool host)
104{
105	/*
106	 * Set up 64-bit inbound regions as the range parser doesn't
107	 * distinguish between 32 and 64-bit types.
108	 */
109	if (host)
110		rcar_pci_write_reg(pcie, lower_32_bits(pci_addr),
111				   PCIEPRAR(idx));
112	rcar_pci_write_reg(pcie, lower_32_bits(cpu_addr), PCIELAR(idx));
113	rcar_pci_write_reg(pcie, flags, PCIELAMR(idx));
114
115	if (host)
116		rcar_pci_write_reg(pcie, upper_32_bits(pci_addr),
117				   PCIEPRAR(idx + 1));
118	rcar_pci_write_reg(pcie, upper_32_bits(cpu_addr), PCIELAR(idx + 1));
119	rcar_pci_write_reg(pcie, 0, PCIELAMR(idx + 1));
120}
121