xref: /openbmc/phosphor-power/pmbus.hpp (revision 96593383)
1 #pragma once
2 
3 #include <filesystem>
4 #include <string>
5 #include <vector>
6 
7 namespace phosphor
8 {
9 namespace pmbus
10 {
11 
12 namespace fs = std::filesystem;
13 
14 // The file name Linux uses to capture the READ_VIN from pmbus.
15 constexpr auto READ_VIN = "in1_input";
16 
17 // The file name Linux uses to capture the MFR_POUT_MAX from pmbus.
18 constexpr auto MFR_POUT_MAX = "max_power_out";
19 // The max_power_out value expected to be read for 1400W IBM CFFPS type.
20 constexpr auto IBM_CFFPS_1400W = 30725;
21 
22 namespace in_input
23 {
24 // VIN thresholds in Volts
25 constexpr auto VIN_VOLTAGE_MIN = 20;
26 constexpr auto VIN_VOLTAGE_110_THRESHOLD = 160;
27 
28 // VIN actual values in Volts
29 // VIN_VOLTAGE_0:   VIN < VIN_VOLTAGE_MIN
30 // VIN_VOLTAGE_110: VIN_VOLTAGE_MIN < VIN < VIN_VOLTAGE_110_THRESHOLD
31 // VIN_VOLTAGE_220: VIN_VOLTAGE_110_THRESHOLD < VIN
32 constexpr auto VIN_VOLTAGE_0 = 0;
33 constexpr auto VIN_VOLTAGE_110 = 110;
34 constexpr auto VIN_VOLTAGE_220 = 220;
35 } // namespace in_input
36 
37 // The file name Linux uses to capture the STATUS_WORD from pmbus.
38 constexpr auto STATUS_WORD = "status0";
39 
40 // The file name Linux uses to capture the STATUS_INPUT from pmbus.
41 constexpr auto STATUS_INPUT = "status0_input";
42 
43 // Voltage out status.
44 // Overvoltage fault or warning, Undervoltage fault or warning, maximum or
45 // minimum warning, ....
46 // Uses Page substitution
47 constexpr auto STATUS_VOUT = "statusP_vout";
48 
49 namespace status_vout
50 {
51 // Mask of bits that are only warnings
52 constexpr auto WARNING_MASK = 0x6A;
53 } // namespace status_vout
54 
55 // Current output status bits.
56 constexpr auto STATUS_IOUT = "status0_iout";
57 
58 // Manufacturing specific status bits
59 constexpr auto STATUS_MFR = "status0_mfr";
60 
61 // Reports on the status of any fans installed in position 1 and 2.
62 constexpr auto STATUS_FANS_1_2 = "status0_fan12";
63 
64 // Reports on temperature faults or warnings. Overtemperature fault,
65 // overtemperature warning, undertemperature warning, undertemperature fault.
66 constexpr auto STATUS_TEMPERATURE = "status0_temp";
67 
68 // Reports on the communication, memory, logic fault(s).
69 constexpr auto STATUS_CML = "status0_cml";
70 
71 namespace status_word
72 {
73 constexpr auto VOUT_FAULT = 0x8000;
74 
75 // The IBM CFF power supply driver does map this bit to power1_alarm in the
76 // hwmon space, but since the other bits that need to be checked do not have
77 // a similar mapping, the code will just read STATUS_WORD and use bit masking
78 // to see if the INPUT FAULT OR WARNING bit is on.
79 constexpr auto INPUT_FAULT_WARN = 0x2000;
80 
81 // The bit mask representing the MFRSPECIFIC fault, bit 4 of STATUS_WORD high
82 // byte. A manufacturer specific fault or warning has occurred.
83 constexpr auto MFR_SPECIFIC_FAULT = 0x1000;
84 
85 // The bit mask representing the POWER_GOOD Negated bit of the STATUS_WORD.
86 constexpr auto POWER_GOOD_NEGATED = 0x0800;
87 
88 // The bit mask representing the FAN FAULT or WARNING bit of the STATUS_WORD.
89 // Bit 2 of the high byte of STATUS_WORD.
90 constexpr auto FAN_FAULT = 0x0400;
91 
92 // The bit mask representing the UNITI_IS_OFF bit of the STATUS_WORD.
93 constexpr auto UNIT_IS_OFF = 0x0040;
94 
95 // Bit 5 of the STATUS_BYTE, or lower byte of STATUS_WORD is used to indicate
96 // an output overvoltage fault.
97 constexpr auto VOUT_OV_FAULT = 0x0020;
98 
99 // The bit mask representing that an output overcurrent fault has occurred.
100 constexpr auto IOUT_OC_FAULT = 0x0010;
101 
102 // The IBM CFF power supply driver does map this bit to in1_alarm, however,
103 // since a number of the other bits are not mapped that way for STATUS_WORD,
104 // this code will just read the entire STATUS_WORD and use bit masking to find
105 // out if that fault is on.
106 constexpr auto VIN_UV_FAULT = 0x0008;
107 
108 // The bit mask representing the TEMPERATURE FAULT or WARNING bit of the
109 // STATUS_WORD. Bit 2 of the low byte (STATUS_BYTE).
110 constexpr auto TEMPERATURE_FAULT_WARN = 0x0004;
111 
112 // The bit mask representing the CML (Communication, Memory, and/or Logic) fault
113 // bit of the STATUS_WORD. Bit 1 of the low byte (STATUS_BYTE).
114 constexpr auto CML_FAULT = 0x0002;
115 } // namespace status_word
116 
117 namespace status_vout
118 {
119 // The IBM CFF power supply driver maps MFR's OV_FAULT and VAUX_FAULT to this
120 // bit.
121 constexpr auto OV_FAULT = 0x80;
122 
123 // The IBM CFF power supply driver maps MFR's UV_FAULT to this bit.
124 constexpr auto UV_FAULT = 0x10;
125 } // namespace status_vout
126 
127 namespace status_temperature
128 {
129 // Overtemperature Fault
130 constexpr auto OT_FAULT = 0x80;
131 } // namespace status_temperature
132 
133 constexpr auto ON_OFF_CONFIG = "on_off_config";
134 
135 // From PMBus Specification Part II Revsion 1.2:
136 // The ON_OFF_CONFIG command configures the combination of CONTROL pin input
137 // and serial bus commands needed to turn the unit on and off. This includes how
138 // the unit responds when power is applied.
139 // Bits [7:5] - 000 - Reserved
140 // Bit 4 - 1 - Unit does not power up until commanded by the CONTROL pin and
141 // OPERATION command (as programmed in bits [3:0]).
142 // Bit 3 - 0 - Unit ignores the on/off portion of the OPERATION command from
143 // serial bus.
144 // Bit 2 - 1 - Unit requires the CONTROL pin to be asserted to start the unit.
145 // Bit 1 - 0 - Polarity of the CONTROL pin. Active low (Pull pin low to start
146 // the unit).
147 // Bit 0 - 1 - Turn off the output and stop transferring energy to the output as
148 // fast as possible.
149 constexpr auto ON_OFF_CONFIG_CONTROL_PIN_ONLY = 0x15;
150 
151 /**
152  * Where the access should be done
153  */
154 enum class Type
155 {
156     Base,            // base device directory
157     Hwmon,           // hwmon directory
158     Debug,           // pmbus debug directory
159     DeviceDebug,     // device debug directory
160     HwmonDeviceDebug // hwmon device debug directory
161 };
162 
163 /**
164  * @class PMBusBase
165  *
166  * This is a base class for PMBus to assist with unit testing via mocking.
167  */
168 class PMBusBase
169 {
170   public:
171     virtual ~PMBusBase() = default;
172 
173     virtual uint64_t read(const std::string& name, Type type,
174                           bool errTrace = true) = 0;
175     virtual std::string readString(const std::string& name, Type type) = 0;
176     virtual std::vector<uint8_t> readBinary(const std::string& name, Type type,
177                                             size_t length) = 0;
178     virtual void writeBinary(const std::string& name, std::vector<uint8_t> data,
179                              Type type) = 0;
180     virtual void findHwmonDir() = 0;
181     virtual const fs::path& path() const = 0;
182     virtual std::string insertPageNum(const std::string& templateName,
183                                       size_t page) = 0;
184 };
185 
186 /**
187  * Wrapper function for PMBus
188  *
189  * @param[in] bus - I2C bus
190  * @param[in] address - I2C address (as a 2-byte string, e.g. 0069)
191  *
192  * @return PMBusBase pointer
193  */
194 std::unique_ptr<PMBusBase> createPMBus(std::uint8_t bus,
195                                        const std::string& address);
196 
197 /**
198  * @class PMBus
199  *
200  * This class is an interface to communicating with PMBus devices
201  * by reading and writing sysfs files.
202  *
203  * Based on the Type parameter, the accesses can either be done
204  * in the base device directory (the one passed into the constructor),
205  * or in the hwmon directory for the device.
206  */
207 class PMBus : public PMBusBase
208 {
209   public:
210     PMBus() = delete;
211     virtual ~PMBus() = default;
212     PMBus(const PMBus&) = default;
213     PMBus& operator=(const PMBus&) = default;
214     PMBus(PMBus&&) = default;
215     PMBus& operator=(PMBus&&) = default;
216 
217     /**
218      * Constructor
219      *
220      * @param[in] path - path to the sysfs directory
221      */
222     PMBus(const std::string& path) : basePath(path)
223     {
224         findHwmonDir();
225     }
226 
227     /**
228      * Constructor
229      *
230      * This version is required when DeviceDebug
231      * access will be used.
232      *
233      * @param[in] path - path to the sysfs directory
234      * @param[in] driverName - the device driver name
235      * @param[in] instance - chip instance number
236      */
237     PMBus(const std::string& path, const std::string& driverName,
238           size_t instance) :
239         basePath(path),
240         driverName(driverName), instance(instance)
241     {
242         findHwmonDir();
243     }
244 
245     /**
246      * Wrapper function for PMBus
247      *
248      * @param[in] bus - I2C bus
249      * @param[in] address - I2C address (as a 2-byte string, e.g. 0069)
250      *
251      * @return PMBusBase pointer
252      */
253     static std::unique_ptr<PMBusBase> createPMBus(std::uint8_t bus,
254                                                   const std::string& address);
255 
256     /**
257      * Reads a file in sysfs that represents a single bit,
258      * therefore doing a PMBus read.
259      *
260      * @param[in] name - path concatenated to
261      *                   basePath to read
262      * @param[in] type - Path type
263      *
264      * @return bool - false if result was 0, else true
265      */
266     bool readBit(const std::string& name, Type type);
267 
268     /**
269      * Reads a file in sysfs that represents a single bit,
270      * where the page number passed in is substituted
271      * into the name in place of the 'P' character in it.
272      *
273      * @param[in] name - path concatenated to
274      *                   basePath to read
275      * @param[in] page - page number
276      * @param[in] type - Path type
277      *
278      * @return bool - false if result was 0, else true
279      */
280     bool readBitInPage(const std::string& name, size_t page, Type type);
281     /**
282      * Checks if the file for the given name and type exists.
283      *
284      * @param[in] name   - path concatenated to basePath to read
285      * @param[in] type   - Path type
286      *
287      * @return bool - True if file exists, false if it does not.
288      */
289     bool exists(const std::string& name, Type type);
290 
291     /**
292      * Read byte(s) from file in sysfs.
293      *
294      * @param[in] name   - path concatenated to basePath to read
295      * @param[in] type   - Path type
296      * @param[in] errTrace - true to enable tracing error (defaults to true)
297      *
298      * @return uint64_t - Up to 8 bytes of data read from file.
299      */
300     uint64_t read(const std::string& name, Type type,
301                   bool errTrace = true) override;
302 
303     /**
304      * Read a string from file in sysfs.
305      *
306      * @param[in] name   - path concatenated to basePath to read
307      * @param[in] type   - Path type
308      *
309      * @return string - The data read from the file.
310      */
311     std::string readString(const std::string& name, Type type) override;
312 
313     /**
314      * Read data from a binary file in sysfs.
315      *
316      * @param[in] name   - path concatenated to basePath to read
317      * @param[in] type   - Path type
318      * @param[in] length - length of data to read, in bytes
319      *
320      * @return vector<uint8_t> - The data read from the file.
321      */
322     std::vector<uint8_t> readBinary(const std::string& name, Type type,
323                                     size_t length);
324 
325     /**
326      * Writes an integer value to the file, therefore doing
327      * a PMBus write.
328      *
329      * @param[in] name - path concatenated to
330      *                   basePath to write
331      * @param[in] value - the value to write
332      * @param[in] type - Path type
333      */
334     void write(const std::string& name, int value, Type type);
335 
336     /**
337      * Writes binary data to a file in sysfs.
338      *
339      * @param[in] name - path concatenated to basePath to write
340      * @param[in] data - The data to write to the file
341      * @param[in] type - Path type
342      */
343     void writeBinary(const std::string& name, std::vector<uint8_t> data,
344                      Type type) override;
345 
346     /**
347      * Returns the sysfs base path of this device
348      */
349     const fs::path& path() const override
350     {
351         return basePath;
352     }
353 
354     /**
355      * Replaces the 'P' in the string passed in with
356      * the page number passed in.
357      *
358      * For example:
359      *   insertPageNum("inP_enable", 42)
360      *   returns "in42_enable"
361      *
362      * @param[in] templateName - the name string, with a 'P' in it
363      * @param[in] page - the page number to insert where the P was
364      *
365      * @return string - the new string with the page number in it
366      */
367     std::string insertPageNum(const std::string& templateName,
368                               size_t page) override;
369 
370     /**
371      * Finds the path relative to basePath to the hwmon directory
372      * for the device and stores it in hwmonRelPath.
373      */
374     void findHwmonDir() override;
375 
376     /**
377      * Returns the path to use for the passed in type.
378      *
379      * @param[in] type - Path type
380      *
381      * @return fs::path - the full path
382      */
383     fs::path getPath(Type type);
384 
385   private:
386     /**
387      * Returns the device name
388      *
389      * This is found in the 'name' file in basePath.
390      *
391      * @return string - the device name
392      */
393     std::string getDeviceName();
394 
395     /**
396      * The sysfs device path
397      */
398     fs::path basePath;
399 
400     /**
401      * The directory name under the basePath hwmon directory
402      */
403     fs::path hwmonDir;
404 
405     /**
406      * The device driver name.  Used for finding the device
407      * debug directory.  Not required if that directory
408      * isn't used.
409      */
410     std::string driverName;
411 
412     /**
413      * The device instance number.
414      *
415      * Used in conjunction with the driver name for finding
416      * the debug directory.  Not required if that directory
417      * isn't used.
418      */
419     size_t instance = 0;
420 
421     /**
422      * The pmbus debug path with status files
423      */
424     const fs::path debugPath = "/sys/kernel/debug/";
425 };
426 
427 } // namespace pmbus
428 } // namespace phosphor
429