xref: /openbmc/u-boot/arch/x86/cpu/qemu/qemu.c (revision 0a61ee88)
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 #include <asm/fw_cfg.h>
15 
16 static bool i440fx;
17 
18 static void qemu_chipset_init(void)
19 {
20 	u16 device, xbcs;
21 	int pam, i;
22 
23 	/*
24 	 * i440FX and Q35 chipset have different PAM register offset, but with
25 	 * the same bitfield layout. Here we determine the offset based on its
26 	 * PCI device ID.
27 	 */
28 	device = x86_pci_read_config16(PCI_BDF(0, 0, 0), PCI_DEVICE_ID);
29 	i440fx = (device == PCI_DEVICE_ID_INTEL_82441);
30 	pam = i440fx ? I440FX_PAM : Q35_PAM;
31 
32 	/*
33 	 * Initialize Programmable Attribute Map (PAM) Registers
34 	 *
35 	 * Configure legacy segments C/D/E/F to system RAM
36 	 */
37 	for (i = 0; i < PAM_NUM; i++)
38 		x86_pci_write_config8(PCI_BDF(0, 0, 0), pam + i, PAM_RW);
39 
40 	if (i440fx) {
41 		/*
42 		 * Enable legacy IDE I/O ports decode
43 		 *
44 		 * Note: QEMU always decode legacy IDE I/O port on PIIX chipset.
45 		 * However Linux ata_piix driver does sanity check on these two
46 		 * registers to see whether legacy ports decode is turned on.
47 		 * This is to make Linux ata_piix driver happy.
48 		 */
49 		x86_pci_write_config16(PIIX_IDE, IDE0_TIM, IDE_DECODE_EN);
50 		x86_pci_write_config16(PIIX_IDE, IDE1_TIM, IDE_DECODE_EN);
51 
52 		/* Enable I/O APIC */
53 		xbcs = x86_pci_read_config16(PIIX_ISA, XBCS);
54 		xbcs |= APIC_EN;
55 		x86_pci_write_config16(PIIX_ISA, XBCS, xbcs);
56 	} else {
57 		/* Configure PCIe ECAM base address */
58 		x86_pci_write_config32(PCI_BDF(0, 0, 0), PCIEX_BAR,
59 				       CONFIG_PCIE_ECAM_BASE | BAR_EN);
60 	}
61 
62 	qemu_fwcfg_init();
63 }
64 
65 int arch_cpu_init(void)
66 {
67 	int ret;
68 
69 	post_code(POST_CPU_INIT);
70 
71 	ret = x86_cpu_init_f();
72 	if (ret)
73 		return ret;
74 
75 	return 0;
76 }
77 
78 #ifndef CONFIG_EFI_STUB
79 int print_cpuinfo(void)
80 {
81 	post_code(POST_CPU_INFO);
82 	return default_print_cpuinfo();
83 }
84 #endif
85 
86 void reset_cpu(ulong addr)
87 {
88 	/* cold reset */
89 	x86_full_reset();
90 }
91 
92 int arch_early_init_r(void)
93 {
94 	qemu_chipset_init();
95 
96 	return 0;
97 }
98 
99 int arch_misc_init(void)
100 {
101 	return pirq_init();
102 }
103 
104 #ifdef CONFIG_GENERATE_MP_TABLE
105 int mp_determine_pci_dstirq(int bus, int dev, int func, int pirq)
106 {
107 	u8 irq;
108 
109 	if (i440fx) {
110 		/*
111 		 * Not like most x86 platforms, the PIRQ[A-D] on PIIX3 are not
112 		 * connected to I/O APIC INTPIN#16-19. Instead they are routed
113 		 * to an irq number controled by the PIRQ routing register.
114 		 */
115 		irq = x86_pci_read_config8(PCI_BDF(bus, dev, func),
116 					   PCI_INTERRUPT_LINE);
117 	} else {
118 		/*
119 		 * ICH9's PIRQ[A-H] are not consecutive numbers from 0 to 7.
120 		 * PIRQ[A-D] still maps to [0-3] but PIRQ[E-H] maps to [8-11].
121 		 */
122 		irq = pirq < 8 ? pirq + 16 : pirq + 12;
123 	}
124 
125 	return irq;
126 }
127 #endif
128