pinctrl/aspeed/pinmux-aspeed.h

12  * basis where a given pin can provide a number of different signal types.
14  * The signal active on a pin is described by both a priority level and
18  * change from a high to low priority signal), or even in the same register.
28  * corner. The signal priorities are in decending order from P0 (highest).
30  * D6 is a pin with a single function (beside GPIO); a high priority signal
33  * Ball | Default | P0 Signal | P0 Expression               | P1 Signal | P1 Expression | Other
38  * C5 is a multi-signal pin (high and low priority signals). Here we touch
39  * different registers for the different functions that enable each signal:
45  * E19 is a single-signal pin with two functions that influence the active
46  * signal. In this case both bits have the same meaning - enable a dedicated
54  * For example, pin B19 has a low-priority signal that's enabled by two
60 …* Ball | Default | P0 Signal | P0 Expression                           | P1 Signal | P1 Expression…
66  * pin's active signal:
79  * Pin T5 is a multi-signal pin with a more complex configuration:
81  * Ball | Default | P0 Signal | P0 Expression                | P1 Signal | P1 Expression | Other
86  * The high priority signal configuration is best thought of in terms of its
103  * function pin", where the signal itself is determined by whether SCU94[5:4]
115  * that despite operating as part of the video input bus each signal needs to
127  * signal's expressions with the function they participate in, rather than
133  * Ball |  Default   | P0 Signal | P0 Expression             | P1 Signal | P1 Expression | Other
139  * A12 demonstrates that the "Other" signal isn't always GPIO - in this case
140  * GPIOT0 is a high-priority signal and RGMII1TXCK is Other. Thus, GPIO
141  * should be treated like any other signal type with full function expression
143  * GPIOT1's signal descriptor bits are distinct, therefore we must iterate all
145  * that the signal for the function of interest is correctly enabled.
157  * * Pins provide up to five signal types in a priority order
159  * * For priorities levels defined on a pin, each priority provides one signal
170  * * A function is described by an expression of one or more signal
173  * * A signal expression is the smallest set of signal descriptors whose
174  *   comparisons must evaluate 'true' for a signal to be enabled on a pin.
176  * * A signal participating in a function is active on a pin if evaluating all
177  *   signal descriptors in the pin's signal expression for the function yields
180  * * A signal at a given priority on a given pin is active if any of the
181  *   functions in which the signal participates are active, and no higher
182  *   priority signal on the pin is active
188  * * To disable a signal, any function(s) activating the signal must be
191  * * Each pin must know the signal expressions of functions in which it
200  * * The VPIDE signal participates in 3 functions: VPI18, VPI24 and VPI30
202  * * The NDCD1 signal participates in just its own NDCD1 function
207  * * The prerequisit for activating the NDCD1 signal is that the VPI18, VPI24
243  * properties associated with a given mux configuration: The pin, the signal,
269  *     .signal = "MAC1LINK",
283  *     .signal = "GPIOA0",
364  *     .signal = "EXTRST",
372  * For ball E19, we have multiple functions enabling a single signal, LPCRST#.
386  *     .signal = "LPCRST",
403  *     .signal = "LPCRST",
428   * A signal descriptor, which describes the register, bits and the
450  * Describes a signal expression. The expression is evaluated by ANDing the
453  * @signal: The signal name for the priority level on the pin. If the signal
454  *          type is GPIO, then the signal name must begin with the
456  * @function: The name of the function the signal participates in for the
458  *            name must match the signal name.
459  * @ndescs: The number of signal descriptors in the expression
460  * @descs: Pointer to an array of signal descriptors that comprise the
464 	const char *signal;  member
472  * for a given pin. The signal configuration for a priority level is evaluated
473  * by ORing the evaluation of the signal expressions in the respective
494  * @reg: The signal's associated register, offset from base
495  * @idx: The signal's bit index in the register
522 		.signal = #sig, \
529  * Declare a signal expression.
531  * @sig: A macro symbol name for the signal (is subjected to stringification
533  * @func: The function in which the signal is participating
534  * @...: Signal descriptors that define the signal expression
536  * For example, the following declares the ROMD8 signal for the ROM16 function:
540  * And with multiple signal descriptors:
550  * Declare a pointer to a signal expression
552  * @sig: The macro symbol name for the signal (subjected to token pasting)
560  * Declare a signal expression list for reference in a struct aspeed_pin_prio.
562  * @sig: A macro symbol name for the signal (is subjected to token pasting)
563  * @...: Signal expression structure pointers (use SIG_EXPR_PTR())
565  * For example, the 16-bit ROM bus can be enabled by one of two possible signal
582  * Create an expression symbol alias from (signal, group) to (pin, signal).
585  * @sig: The signal name
587  *         associated with the function's signal
590  * the signal for a group multiple times) whilst enabling multiple pin groups
591  * to exist for a signal without intrusive side-effects on defining the list of
603  * @pin: The pin the signal will be routed to
604  * @sig: The signal that will be routed to the pin for the function
608  * For example, signal NCTS6 participates in its own function with one group:
622  * @pin: The pin the signal will be routed to
623  * @sig: The signal that will be routed to the pin for the function
638  * @pin: The pin the signal will be routed to
639  * @sig: The signal that will be routed to the pin for the function
663  * Declare a single signal pin
667  * @sig: Macro name for the signal (subjected to stringification)
681  * Single signal, single function pin declaration
685  * @sig: Macro name for the signal (subjected to stringification)
686  * @...: Signal descriptors that define the function expression
699  * Declare a two-signal pin
703  * @high: Macro name for the highest priority signal functions
704  * @low: Macro name for the low signal functions