xref: /openbmc/u-boot/arch/x86/cpu/qemu/qemu.c (revision 872cfa20)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
4  */
5 
6 #include <common.h>
7 #include <pci.h>
8 #include <qfw.h>
9 #include <asm/irq.h>
10 #include <asm/post.h>
11 #include <asm/processor.h>
12 #include <asm/arch/device.h>
13 #include <asm/arch/qemu.h>
14 
15 static bool i440fx;
16 
17 #ifdef CONFIG_QFW
18 
19 /* on x86, the qfw registers are all IO ports */
20 #define FW_CONTROL_PORT	0x510
21 #define FW_DATA_PORT		0x511
22 #define FW_DMA_PORT_LOW	0x514
23 #define FW_DMA_PORT_HIGH	0x518
24 
25 static void qemu_x86_fwcfg_read_entry_pio(uint16_t entry,
26 		uint32_t size, void *address)
27 {
28 	uint32_t i = 0;
29 	uint8_t *data = address;
30 
31 	/*
32 	 * writting FW_CFG_INVALID will cause read operation to resume at
33 	 * last offset, otherwise read will start at offset 0
34 	 *
35 	 * Note: on platform where the control register is IO port, the
36 	 * endianness is little endian.
37 	 */
38 	if (entry != FW_CFG_INVALID)
39 		outw(cpu_to_le16(entry), FW_CONTROL_PORT);
40 
41 	/* the endianness of data register is string-preserving */
42 	while (size--)
43 		data[i++] = inb(FW_DATA_PORT);
44 }
45 
46 static void qemu_x86_fwcfg_read_entry_dma(struct fw_cfg_dma_access *dma)
47 {
48 	/* the DMA address register is big endian */
49 	outl(cpu_to_be32((uintptr_t)dma), FW_DMA_PORT_HIGH);
50 
51 	while (be32_to_cpu(dma->control) & ~FW_CFG_DMA_ERROR)
52 		__asm__ __volatile__ ("pause");
53 }
54 
55 static struct fw_cfg_arch_ops fwcfg_x86_ops = {
56 	.arch_read_pio = qemu_x86_fwcfg_read_entry_pio,
57 	.arch_read_dma = qemu_x86_fwcfg_read_entry_dma
58 };
59 #endif
60 
61 static void enable_pm_piix(void)
62 {
63 	u8 en;
64 	u16 cmd;
65 
66 	/* Set the PM I/O base */
67 	pci_write_config32(PIIX_PM, PMBA, CONFIG_ACPI_PM1_BASE | 1);
68 
69 	/* Enable access to the PM I/O space */
70 	pci_read_config16(PIIX_PM, PCI_COMMAND, &cmd);
71 	cmd |= PCI_COMMAND_IO;
72 	pci_write_config16(PIIX_PM, PCI_COMMAND, cmd);
73 
74 	/* PM I/O Space Enable (PMIOSE) */
75 	pci_read_config8(PIIX_PM, PMREGMISC, &en);
76 	en |= PMIOSE;
77 	pci_write_config8(PIIX_PM, PMREGMISC, en);
78 }
79 
80 static void enable_pm_ich9(void)
81 {
82 	/* Set the PM I/O base */
83 	pci_write_config32(ICH9_PM, PMBA, CONFIG_ACPI_PM1_BASE | 1);
84 }
85 
86 static void qemu_chipset_init(void)
87 {
88 	u16 device, xbcs;
89 	int pam, i;
90 
91 	/*
92 	 * i440FX and Q35 chipset have different PAM register offset, but with
93 	 * the same bitfield layout. Here we determine the offset based on its
94 	 * PCI device ID.
95 	 */
96 	pci_read_config16(PCI_BDF(0, 0, 0), PCI_DEVICE_ID, &device);
97 	i440fx = (device == PCI_DEVICE_ID_INTEL_82441);
98 	pam = i440fx ? I440FX_PAM : Q35_PAM;
99 
100 	/*
101 	 * Initialize Programmable Attribute Map (PAM) Registers
102 	 *
103 	 * Configure legacy segments C/D/E/F to system RAM
104 	 */
105 	for (i = 0; i < PAM_NUM; i++)
106 		pci_write_config8(PCI_BDF(0, 0, 0), pam + i, PAM_RW);
107 
108 	if (i440fx) {
109 		/*
110 		 * Enable legacy IDE I/O ports decode
111 		 *
112 		 * Note: QEMU always decode legacy IDE I/O port on PIIX chipset.
113 		 * However Linux ata_piix driver does sanity check on these two
114 		 * registers to see whether legacy ports decode is turned on.
115 		 * This is to make Linux ata_piix driver happy.
116 		 */
117 		pci_write_config16(PIIX_IDE, IDE0_TIM, IDE_DECODE_EN);
118 		pci_write_config16(PIIX_IDE, IDE1_TIM, IDE_DECODE_EN);
119 
120 		/* Enable I/O APIC */
121 		pci_read_config16(PIIX_ISA, XBCS, &xbcs);
122 		xbcs |= APIC_EN;
123 		pci_write_config16(PIIX_ISA, XBCS, xbcs);
124 
125 		enable_pm_piix();
126 	} else {
127 		/* Configure PCIe ECAM base address */
128 		pci_write_config32(PCI_BDF(0, 0, 0), PCIEX_BAR,
129 				   CONFIG_PCIE_ECAM_BASE | BAR_EN);
130 
131 		enable_pm_ich9();
132 	}
133 
134 #ifdef CONFIG_QFW
135 	qemu_fwcfg_init(&fwcfg_x86_ops);
136 #endif
137 }
138 
139 #if !CONFIG_IS_ENABLED(SPL_X86_32BIT_INIT)
140 int arch_cpu_init(void)
141 {
142 	post_code(POST_CPU_INIT);
143 
144 	return x86_cpu_init_f();
145 }
146 
147 int checkcpu(void)
148 {
149 	return 0;
150 }
151 
152 int print_cpuinfo(void)
153 {
154 	post_code(POST_CPU_INFO);
155 	return default_print_cpuinfo();
156 }
157 #endif
158 
159 int arch_early_init_r(void)
160 {
161 	qemu_chipset_init();
162 
163 	return 0;
164 }
165 
166 #ifdef CONFIG_GENERATE_MP_TABLE
167 int mp_determine_pci_dstirq(int bus, int dev, int func, int pirq)
168 {
169 	u8 irq;
170 
171 	if (i440fx) {
172 		/*
173 		 * Not like most x86 platforms, the PIRQ[A-D] on PIIX3 are not
174 		 * connected to I/O APIC INTPIN#16-19. Instead they are routed
175 		 * to an irq number controled by the PIRQ routing register.
176 		 */
177 		pci_read_config8(PCI_BDF(bus, dev, func),
178 				 PCI_INTERRUPT_LINE, &irq);
179 	} else {
180 		/*
181 		 * ICH9's PIRQ[A-H] are not consecutive numbers from 0 to 7.
182 		 * PIRQ[A-D] still maps to [0-3] but PIRQ[E-H] maps to [8-11].
183 		 */
184 		irq = pirq < 8 ? pirq + 16 : pirq + 12;
185 	}
186 
187 	return irq;
188 }
189 #endif
190