30 lines
988 B
Plaintext
30 lines
988 B
Plaintext
Altera Passive Serial SPI FPGA Manager
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Altera FPGAs support a method of loading the bitstream over what is
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referred to as "passive serial".
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The passive serial link is not technically SPI, and might require extra
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circuits in order to play nicely with other SPI slaves on the same bus.
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See https://www.altera.com/literature/hb/cyc/cyc_c51013.pdf
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Required properties:
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- compatible: Must be one of the following:
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"altr,fpga-passive-serial",
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"altr,fpga-arria10-passive-serial"
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- reg: SPI chip select of the FPGA
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- nconfig-gpios: config pin (referred to as nCONFIG in the manual)
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- nstat-gpios: status pin (referred to as nSTATUS in the manual)
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Optional properties:
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- confd-gpios: confd pin (referred to as CONF_DONE in the manual)
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Example:
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fpga: fpga@0 {
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compatible = "altr,fpga-passive-serial";
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spi-max-frequency = <20000000>;
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reg = <0>;
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nconfig-gpios = <&gpio4 9 GPIO_ACTIVE_LOW>;
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nstat-gpios = <&gpio4 11 GPIO_ACTIVE_LOW>;
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confd-gpios = <&gpio4 12 GPIO_ACTIVE_LOW>;
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};
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