xref: /openbmc/qemu/hw/misc/imx7_gpr.c (revision 500eb6db)
1 /*
2  * Copyright (c) 2018, Impinj, Inc.
3  *
4  * i.MX7 GPR IP block emulation code
5  *
6  * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or later.
9  * See the COPYING file in the top-level directory.
10  *
11  * Bare minimum emulation code needed to support being able to shut
12  * down linux guest gracefully.
13  */
14 
15 #include "qemu/osdep.h"
16 #include "hw/misc/imx7_gpr.h"
17 #include "qemu/log.h"
18 #include "qemu/module.h"
19 #include "sysemu/sysemu.h"
20 
21 #include "trace.h"
22 
23 enum IMX7GPRRegisters {
24     IOMUXC_GPR0  = 0x00,
25     IOMUXC_GPR1  = 0x04,
26     IOMUXC_GPR2  = 0x08,
27     IOMUXC_GPR3  = 0x0c,
28     IOMUXC_GPR4  = 0x10,
29     IOMUXC_GPR5  = 0x14,
30     IOMUXC_GPR6  = 0x18,
31     IOMUXC_GPR7  = 0x1c,
32     IOMUXC_GPR8  = 0x20,
33     IOMUXC_GPR9  = 0x24,
34     IOMUXC_GPR10 = 0x28,
35     IOMUXC_GPR11 = 0x2c,
36     IOMUXC_GPR12 = 0x30,
37     IOMUXC_GPR13 = 0x34,
38     IOMUXC_GPR14 = 0x38,
39     IOMUXC_GPR15 = 0x3c,
40     IOMUXC_GPR16 = 0x40,
41     IOMUXC_GPR17 = 0x44,
42     IOMUXC_GPR18 = 0x48,
43     IOMUXC_GPR19 = 0x4c,
44     IOMUXC_GPR20 = 0x50,
45     IOMUXC_GPR21 = 0x54,
46     IOMUXC_GPR22 = 0x58,
47 };
48 
49 #define IMX7D_GPR1_IRQ_MASK                 BIT(12)
50 #define IMX7D_GPR1_ENET1_TX_CLK_SEL_MASK    BIT(13)
51 #define IMX7D_GPR1_ENET2_TX_CLK_SEL_MASK    BIT(14)
52 #define IMX7D_GPR1_ENET_TX_CLK_SEL_MASK     (0x3 << 13)
53 #define IMX7D_GPR1_ENET1_CLK_DIR_MASK       BIT(17)
54 #define IMX7D_GPR1_ENET2_CLK_DIR_MASK       BIT(18)
55 #define IMX7D_GPR1_ENET_CLK_DIR_MASK        (0x3 << 17)
56 
57 #define IMX7D_GPR5_CSI_MUX_CONTROL_MIPI     BIT(4)
58 #define IMX7D_GPR12_PCIE_PHY_REFCLK_SEL     BIT(5)
59 #define IMX7D_GPR22_PCIE_PHY_PLL_LOCKED     BIT(31)
60 
61 
62 static uint64_t imx7_gpr_read(void *opaque, hwaddr offset, unsigned size)
63 {
64     trace_imx7_gpr_read(offset);
65 
66     if (offset == IOMUXC_GPR22) {
67         return IMX7D_GPR22_PCIE_PHY_PLL_LOCKED;
68     }
69 
70     return 0;
71 }
72 
73 static void imx7_gpr_write(void *opaque, hwaddr offset,
74                            uint64_t v, unsigned size)
75 {
76     trace_imx7_gpr_write(offset, v);
77 }
78 
79 static const struct MemoryRegionOps imx7_gpr_ops = {
80     .read = imx7_gpr_read,
81     .write = imx7_gpr_write,
82     .endianness = DEVICE_NATIVE_ENDIAN,
83     .impl = {
84         /*
85          * Our device would not work correctly if the guest was doing
86          * unaligned access. This might not be a limitation on the
87          * real device but in practice there is no reason for a guest
88          * to access this device unaligned.
89          */
90         .min_access_size = 4,
91         .max_access_size = 4,
92         .unaligned = false,
93     },
94 };
95 
96 static void imx7_gpr_init(Object *obj)
97 {
98     SysBusDevice *sd = SYS_BUS_DEVICE(obj);
99     IMX7GPRState *s = IMX7_GPR(obj);
100 
101     memory_region_init_io(&s->mmio, obj, &imx7_gpr_ops, s,
102                           TYPE_IMX7_GPR, 64 * 1024);
103     sysbus_init_mmio(sd, &s->mmio);
104 }
105 
106 static void imx7_gpr_class_init(ObjectClass *klass, void *data)
107 {
108     DeviceClass *dc = DEVICE_CLASS(klass);
109 
110     dc->desc  = "i.MX7 General Purpose Registers Module";
111 }
112 
113 static const TypeInfo imx7_gpr_info = {
114     .name          = TYPE_IMX7_GPR,
115     .parent        = TYPE_SYS_BUS_DEVICE,
116     .instance_size = sizeof(IMX7GPRState),
117     .instance_init = imx7_gpr_init,
118     .class_init    = imx7_gpr_class_init,
119 };
120 
121 static void imx7_gpr_register_type(void)
122 {
123     type_register_static(&imx7_gpr_info);
124 }
125 type_init(imx7_gpr_register_type)
126