xref: /openbmc/u-boot/arch/x86/cpu/qemu/qemu.c (revision c5f18a0b)
1 /*
2  * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <asm/irq.h>
9 #include <asm/pci.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 static void qemu_chipset_init(void)
18 {
19 	u16 device, xbcs;
20 	int pam, i;
21 
22 	/*
23 	 * i440FX and Q35 chipset have different PAM register offset, but with
24 	 * the same bitfield layout. Here we determine the offset based on its
25 	 * PCI device ID.
26 	 */
27 	device = x86_pci_read_config16(PCI_BDF(0, 0, 0), PCI_DEVICE_ID);
28 	i440fx = (device == PCI_DEVICE_ID_INTEL_82441);
29 	pam = i440fx ? I440FX_PAM : Q35_PAM;
30 
31 	/*
32 	 * Initialize Programmable Attribute Map (PAM) Registers
33 	 *
34 	 * Configure legacy segments C/D/E/F to system RAM
35 	 */
36 	for (i = 0; i < PAM_NUM; i++)
37 		x86_pci_write_config8(PCI_BDF(0, 0, 0), pam + i, PAM_RW);
38 
39 	if (i440fx) {
40 		/*
41 		 * Enable legacy IDE I/O ports decode
42 		 *
43 		 * Note: QEMU always decode legacy IDE I/O port on PIIX chipset.
44 		 * However Linux ata_piix driver does sanity check on these two
45 		 * registers to see whether legacy ports decode is turned on.
46 		 * This is to make Linux ata_piix driver happy.
47 		 */
48 		x86_pci_write_config16(PIIX_IDE, IDE0_TIM, IDE_DECODE_EN);
49 		x86_pci_write_config16(PIIX_IDE, IDE1_TIM, IDE_DECODE_EN);
50 
51 		/* Enable I/O APIC */
52 		xbcs = x86_pci_read_config16(PIIX_ISA, XBCS);
53 		xbcs |= APIC_EN;
54 		x86_pci_write_config16(PIIX_ISA, XBCS, xbcs);
55 	} else {
56 		/* Configure PCIe ECAM base address */
57 		x86_pci_write_config32(PCI_BDF(0, 0, 0), PCIEX_BAR,
58 				       CONFIG_PCIE_ECAM_BASE | BAR_EN);
59 	}
60 }
61 
62 int arch_cpu_init(void)
63 {
64 	int ret;
65 
66 	post_code(POST_CPU_INIT);
67 
68 	ret = x86_cpu_init_f();
69 	if (ret)
70 		return ret;
71 
72 	return 0;
73 }
74 
75 #ifndef CONFIG_EFI_STUB
76 int print_cpuinfo(void)
77 {
78 	post_code(POST_CPU_INFO);
79 	return default_print_cpuinfo();
80 }
81 #endif
82 
83 void reset_cpu(ulong addr)
84 {
85 	/* cold reset */
86 	x86_full_reset();
87 }
88 
89 int arch_early_init_r(void)
90 {
91 	qemu_chipset_init();
92 
93 	return 0;
94 }
95 
96 int arch_misc_init(void)
97 {
98 	return pirq_init();
99 }
100 
101 #ifdef CONFIG_GENERATE_MP_TABLE
102 int mp_determine_pci_dstirq(int bus, int dev, int func, int pirq)
103 {
104 	u8 irq;
105 
106 	if (i440fx) {
107 		/*
108 		 * Not like most x86 platforms, the PIRQ[A-D] on PIIX3 are not
109 		 * connected to I/O APIC INTPIN#16-19. Instead they are routed
110 		 * to an irq number controled by the PIRQ routing register.
111 		 */
112 		irq = x86_pci_read_config8(PCI_BDF(bus, dev, func),
113 					   PCI_INTERRUPT_LINE);
114 	} else {
115 		/*
116 		 * ICH9's PIRQ[A-H] are not consecutive numbers from 0 to 7.
117 		 * PIRQ[A-D] still maps to [0-3] but PIRQ[E-H] maps to [8-11].
118 		 */
119 		irq = pirq < 8 ? pirq + 16 : pirq + 12;
120 	}
121 
122 	return irq;
123 }
124 #endif
125