platform/atom/punit_atom_debug.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Intel SOC Punit device state debug driver
0004  * Punit controls power management for North Complex devices (Graphics
0005  * blocks, Image Signal Processing, video processing, display, DSP etc.)
0006  *
0007  * Copyright (c) 2015, Intel Corporation.
0008  */
0009
0010 #include <linux/module.h>
0011 #include <linux/init.h>
0012 #include <linux/device.h>
0013 #include <linux/debugfs.h>
0014 #include <linux/seq_file.h>
0015 #include <linux/io.h>
0016 #include <asm/cpu_device_id.h>
0017 #include <asm/intel-family.h>
0018 #include <asm/iosf_mbi.h>
0019
0020 /* Subsystem config/status Video processor */
0021 #define VED_SS_PM0      0x32
0022 /* Subsystem config/status ISP (Image Signal Processor) */
0023 #define ISP_SS_PM0      0x39
0024 /* Subsystem config/status Input/output controller */
0025 #define MIO_SS_PM       0x3B
0026 /* Shift bits for getting status for video, isp and i/o */
0027 #define SSS_SHIFT       24
0028
0029 /* Power gate status reg */
0030 #define PWRGT_STATUS        0x61
0031 /* Shift bits for getting status for graphics rendering */
0032 #define RENDER_POS      0
0033 /* Shift bits for getting status for media control */
0034 #define MEDIA_POS       2
0035 /* Shift bits for getting status for Valley View/Baytrail display */
0036 #define VLV_DISPLAY_POS     6
0037
0038 /* Subsystem config/status display for Cherry Trail SOC */
0039 #define CHT_DSP_SSS     0x36
0040 /* Shift bits for getting status for display */
0041 #define CHT_DSP_SSS_POS     16
0042
0043 struct punit_device {
0044     char *name;
0045     int reg;
0046     int sss_pos;
0047 };
0048
0049 static const struct punit_device punit_device_tng[] = {
0050     { "DISPLAY",    CHT_DSP_SSS,    SSS_SHIFT },
0051     { "VED",    VED_SS_PM0, SSS_SHIFT },
0052     { "ISP",    ISP_SS_PM0, SSS_SHIFT },
0053     { "MIO",    MIO_SS_PM,  SSS_SHIFT },
0054     { NULL }
0055 };
0056
0057 static const struct punit_device punit_device_byt[] = {
0058     { "GFX RENDER", PWRGT_STATUS,   RENDER_POS },
0059     { "GFX MEDIA",  PWRGT_STATUS,   MEDIA_POS },
0060     { "DISPLAY",    PWRGT_STATUS,   VLV_DISPLAY_POS },
0061     { "VED",    VED_SS_PM0, SSS_SHIFT },
0062     { "ISP",    ISP_SS_PM0, SSS_SHIFT },
0063     { "MIO",    MIO_SS_PM,  SSS_SHIFT },
0064     { NULL }
0065 };
0066
0067 static const struct punit_device punit_device_cht[] = {
0068     { "GFX RENDER", PWRGT_STATUS,   RENDER_POS },
0069     { "GFX MEDIA",  PWRGT_STATUS,   MEDIA_POS },
0070     { "DISPLAY",    CHT_DSP_SSS,    CHT_DSP_SSS_POS },
0071     { "VED",    VED_SS_PM0, SSS_SHIFT },
0072     { "ISP",    ISP_SS_PM0, SSS_SHIFT },
0073     { "MIO",    MIO_SS_PM,  SSS_SHIFT },
0074     { NULL }
0075 };
0076
0077 static const char * const dstates[] = {"D0", "D0i1", "D0i2", "D0i3"};
0078
0079 static int punit_dev_state_show(struct seq_file *seq_file, void *unused)
0080 {
0081     u32 punit_pwr_status;
0082     struct punit_device *punit_devp = seq_file->private;
0083     int index;
0084     int status;
0085
0086     seq_puts(seq_file, "\n\nPUNIT NORTH COMPLEX DEVICES :\n");
0087     while (punit_devp->name) {
0088         status = iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ,
0089                        punit_devp->reg, &punit_pwr_status);
0090         if (status) {
0091             seq_printf(seq_file, "%9s : Read Failed\n",
0092                    punit_devp->name);
0093         } else  {
0094             index = (punit_pwr_status >> punit_devp->sss_pos) & 3;
0095             seq_printf(seq_file, "%9s : %s\n", punit_devp->name,
0096                    dstates[index]);
0097         }
0098         punit_devp++;
0099     }
0100
0101     return 0;
0102 }
0103 DEFINE_SHOW_ATTRIBUTE(punit_dev_state);
0104
0105 static struct dentry *punit_dbg_file;
0106
0107 static void punit_dbgfs_register(struct punit_device *punit_device)
0108 {
0109     punit_dbg_file = debugfs_create_dir("punit_atom", NULL);
0110
0111     debugfs_create_file("dev_power_state", 0444, punit_dbg_file,
0112                 punit_device, &punit_dev_state_fops);
0113 }
0114
0115 static void punit_dbgfs_unregister(void)
0116 {
0117     debugfs_remove_recursive(punit_dbg_file);
0118 }
0119
0120 #define X86_MATCH(model, data)                       \
0121     X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_##model, \
0122                        X86_FEATURE_MWAIT, data)
0123
0124 static const struct x86_cpu_id intel_punit_cpu_ids[] = {
0125     X86_MATCH(ATOM_SILVERMONT,      &punit_device_byt),
0126     X86_MATCH(ATOM_SILVERMONT_MID,      &punit_device_tng),
0127     X86_MATCH(ATOM_AIRMONT,         &punit_device_cht),
0128     {}
0129 };
0130 MODULE_DEVICE_TABLE(x86cpu, intel_punit_cpu_ids);
0131
0132 static int __init punit_atom_debug_init(void)
0133 {
0134     const struct x86_cpu_id *id;
0135
0136     id = x86_match_cpu(intel_punit_cpu_ids);
0137     if (!id)
0138         return -ENODEV;
0139
0140     punit_dbgfs_register((struct punit_device *)id->driver_data);
0141
0142     return 0;
0143 }
0144
0145 static void __exit punit_atom_debug_exit(void)
0146 {
0147     punit_dbgfs_unregister();
0148 }
0149
0150 module_init(punit_atom_debug_init);
0151 module_exit(punit_atom_debug_exit);
0152
0153 MODULE_AUTHOR("Kumar P, Mahesh <mahesh.kumar.p@intel.com>");
0154 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
0155 MODULE_DESCRIPTION("Driver for Punit devices states debugging");
0156 MODULE_LICENSE("GPL v2");