33 строки
1.1 KiB
Plaintext
33 строки
1.1 KiB
Plaintext
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Clock framework on SuperH architecture
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The framework on SH extends existing API by the function clk_set_rate_ex,
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which prototype is as follows:
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clk_set_rate_ex (struct clk *clk, unsigned long rate, int algo_id)
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The algo_id parameter is used to specify algorithm used to recalculate clocks,
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adjanced to clock, specified as first argument. It is assumed that algo_id==0
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means no changes to adjanced clock
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Internally, the clk_set_rate_ex forwards request to clk->ops->set_rate method,
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if it is present in ops structure. The method should set the clock rate and adjust
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all needed clocks according to the passed algo_id.
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Exact values for algo_id are machine-dependend. For the sh7722, the following
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values are defined:
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NO_CHANGE = 0,
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IUS_N1_N1, /* I:U = N:1, U:Sh = N:1 */
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IUS_322, /* I:U:Sh = 3:2:2 */
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IUS_522, /* I:U:Sh = 5:2:2 */
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IUS_N11, /* I:U:Sh = N:1:1 */
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SB_N1, /* Sh:B = N:1 */
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SB3_N1, /* Sh:B3 = N:1 */
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SB3_32, /* Sh:B3 = 3:2 */
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SB3_43, /* Sh:B3 = 4:3 */
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SB3_54, /* Sh:B3 = 5:4 */
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BP_N1, /* B:P = N:1 */
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IP_N1 /* I:P = N:1 */
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Each of these constants means relation between clocks that can be set via the FRQCR
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register
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