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 
rcar_pci_write_reg(struct rcar_pcie * pcie,u32 val,unsigned int reg)14 void rcar_pci_write_reg(struct rcar_pcie *pcie, u32 val, unsigned int reg)
15 {
16 	writel(val, pcie->base + reg);
17 }
18 
rcar_pci_read_reg(struct rcar_pcie * pcie,unsigned int reg)19 u32 rcar_pci_read_reg(struct rcar_pcie *pcie, unsigned int reg)
20 {
21 	return readl(pcie->base + reg);
22 }
23 
rcar_rmw32(struct rcar_pcie * pcie,int where,u32 mask,u32 data)24 void 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 
rcar_pcie_wait_for_phyrdy(struct rcar_pcie * pcie)34 int 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 
rcar_pcie_wait_for_dl(struct rcar_pcie * pcie)48 int 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 
rcar_pcie_set_outbound(struct rcar_pcie * pcie,int win,struct resource_entry * window)63 void 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 
rcar_pcie_set_inbound(struct rcar_pcie * pcie,u64 cpu_addr,u64 pci_addr,u64 flags,int idx,bool host)102 void 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