ra8_mipi_phy_timing.c File Reference

MIPI D-PHY driver – HUM timing tables and table-driven setup. More...

#include <stdint.h>
#include "ra8_attributes.h"
#include "ra8_err.h"
#include "ra8_mipi_phy.h"
#include "ra8_mipi_phy_internal.h"
#include "ra8_mipi_phy_regs.h"

Include dependency graph for ra8_mipi_phy_timing.c:

Go to the source code of this file.

Data Structures
struct	mipi_phy_table_row_t
	One row of HUM Tables 64.2 / 64.3 with the rate ceiling. More...

Enumerations
enum	mipi_pll_frac_t : uint16_t {   k_mipi_pll_percent_scale = 100U ,   k_mipi_nf_x100_33 = 33U ,   k_mipi_nf_x100_66 = 66U ,   k_mipi_nf_x100_50 = 50U }
	PLL fixed-point (hundredths) scale and NF fractional table. More...
enum	ra8_mipi_phy_table_szlim_t : uint8_t {   k_ra8_mipi_phy_table_pclka_125 = 125U ,   k_ra8_mipi_phy_table_pclka_120 = 120U ,   k_ra8_mipi_phy_table_pclka_100 = 100U ,   k_ra8_mipi_phy_table_pclka_80 = 80U ,   k_ra8_mipi_phy_table_pclka_75 = 75U ,   k_ra8_mipi_phy_table_pclka_50 = 50U ,   k_ra8_mipi_phy_table_pclka_40 = 40U }
	Static lookup-table cardinalities. More...

Functions
static const ra8_mipi_phy_timing_t *	internal_mipi_phy_lookup_timing (const mipi_phy_table_row_t *tbl, uint32_t n, uint8_t pclka, uint16_t rate_mbps, uint8_t mode_flag)
	Lookup helper – linear scan picks the first row whose rate_max is >= the requested rate within a matching PCLKA bucket.
uint32_t	priv_mipi_phy_compute_freq (const ra8_mipi_phy_pll_t *pll, uint8_t mosc_mhz)
	Compute the PLL output frequency for a (mosc, pll) tuple.
ra8_err_t	ra8_mipi_phy_select_timing (ra8_mipi_phy_mode_t mode, uint8_t pclka_mhz, uint16_t rate_mbps, ra8_mipi_phy_timing_t *const out_timing)
	Look up an HUM Table 64.2 / 64.3 row and apply the timing.

Variables
static const mipi_phy_table_row_t	s_dsi_table []
	HUM Table 64.2 D-PHY timing setting DSI mode (p 3831-3834).
static const mipi_phy_table_row_t	s_csi_table []
	HUM Table 64.3 D-PHY timing setting CSI mode (p 3835-3836).

Detailed Description

MIPI D-PHY driver – HUM timing tables and table-driven setup.

Tag

[Ring 3 / HAL] {World: NS}

This translation unit holds the bulky portion of the MIPI D-PHY driver that ra8_mipi_phy.c delegates to so that neither file exceeds the scripts/checks/check_file_size.py cap. It owns:

• The flattened representations of HUM Table 64.2 (D-PHY timing setting DSI mode, p 3831-3834) and HUM Table 64.3 (D-PHY timing setting CSI mode, p 3835-3836) as static lookup tables.
• The linear-scan lookup walker that picks the correct row for a requested (mode, pclka, rate) tuple.
• ra8_mipi_phy_select_timing, the public table-driven entry point that selects a row and programs DPHYTIM1..6.
• priv_mipi_phy_compute_freq, the HUM 64.2.2 PLL-frequency arithmetic helper consumed by ra8_mipi_phy_validate_pll_band in ra8_mipi_phy.c.

The register-write path used by ra8_mipi_phy_select_timing lives in ra8_mipi_phy.c (priv_mipi_phy_write_timing) and is reached through ra8_mipi_phy_internal.h.

Copyright

Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since

0.1.0

Definition in file ra8_mipi_phy_timing.c.

Enumeration Type Documentation

mipi_pll_frac_t

enum mipi_pll_frac_t : uint16_t

PLL fixed-point (hundredths) scale and NF fractional table.

Enumerator
k_mipi_pll_percent_scale	Hundredths fixed-point scale.
k_mipi_nf_x100_33	NF = 0.33 (x100).
k_mipi_nf_x100_66	NF = 0.66 (x100).
k_mipi_nf_x100_50	NF = 0.50 (x100).

Definition at line 42 of file ra8_mipi_phy_timing.c.

ra8_mipi_phy_table_szlim_t

enum ra8_mipi_phy_table_szlim_t : uint8_t

Static lookup-table cardinalities.

Enumerator
k_ra8_mipi_phy_table_pclka_125	PCLKA 125 MHz bucket.
k_ra8_mipi_phy_table_pclka_120	PCLKA 120 MHz bucket.
k_ra8_mipi_phy_table_pclka_100	PCLKA 100 MHz bucket.
k_ra8_mipi_phy_table_pclka_80	PCLKA 80 MHz bucket.
k_ra8_mipi_phy_table_pclka_75	PCLKA 75 MHz bucket.
k_ra8_mipi_phy_table_pclka_50	PCLKA 50 MHz bucket.
k_ra8_mipi_phy_table_pclka_40	PCLKA 40 MHz bucket.

Definition at line 79 of file ra8_mipi_phy_timing.c.

Function Documentation

internal_mipi_phy_lookup_timing()

const ra8_mipi_phy_timing_t * internal_mipi_phy_lookup_timing ( const mipi_phy_table_row_t * tbl, uint32_t n, uint8_t pclka, uint16_t rate_mbps, uint8_t mode_flag )

static

Lookup helper – linear scan picks the first row whose rate_max is >= the requested rate within a matching PCLKA bucket.

Definition at line 865 of file ra8_mipi_phy_timing.c.

References mipi_phy_table_row_t::t.

Referenced by ra8_mipi_phy_select_timing().

priv_mipi_phy_compute_freq()

uint32_t priv_mipi_phy_compute_freq	(	const ra8_mipi_phy_pll_t *	pll,
		uint8_t	mosc_mhz )

Compute the PLL output frequency for a (mosc, pll) tuple.

Defined in ra8_mipi_phy_timing.c and shared with ra8_mipi_phy_validate_pll_band in ra8_mipi_phy.c. Implements the HUM Ch 64.2.2 p 3823 relation f = fMAIN * I * (NF + N) * P using hundredths fixed-point arithmetic.

Parameters

[in]	pll	PLL coefficient block (IDIV / NFMUL / PMUL / NMUL).
[in]	mosc_mhz	Main-oscillator frequency in MHz.

Returns

PLL output frequency in MHz, or 0 if the divisor product is 0.

Return values

0	The composed divisor product was zero.
other	Computed PLL output frequency in MHz.

Precondition

pll is a valid, non-NULL ra8_mipi_phy_pll_t.

mosc_mhz is a non-zero main-oscillator frequency.

Postcondition

No register or shared state is modified by this helper.

The return value is a pure function of the two arguments.

Note

Internal helper. Not thread-safe; caller provides synchronisation.

Since

0.1.0

Definition at line 880 of file ra8_mipi_phy_timing.c.

References ra8_mipi_phy_pll_t::idiv, k_mipi_nf_x100_33, k_mipi_nf_x100_50, k_mipi_nf_x100_66, k_mipi_pll_percent_scale, ra8_mipi_phy_pll_t::nfmul, ra8_mipi_phy_pll_t::nmul_int, and ra8_mipi_phy_pll_t::pmul.

Referenced by ra8_mipi_phy_validate_pll_band().

ra8_mipi_phy_select_timing()

ra8_err_t ra8_mipi_phy_select_timing ( ra8_mipi_phy_mode_t mode, uint8_t pclka_mhz, uint16_t rate_mbps, ra8_mipi_phy_timing_t * out_timing )

nodiscard

Look up an HUM Table 64.2 / 64.3 row and apply the timing.

Tables 64.2 (DSI mode, p 3831-3834) and 64.3 (CSI mode, p 3835-3836) map (PCLKA, lane_rate_mbps) to a ready-made set of DPHYTIMx field values. This helper picks the closest row, fills in a ra8_mipi_phy_timing_t, and writes DPHYTIM1..6.

Parameters

[in]	mode	Active mode (DSI vs CSI uses different tables).
[in]	pclka_mhz	PCLKA frequency in MHz.
[in]	rate_mbps	Per-lane line rate in Mbps.
[out]	out_timing	Optional non-NULL pointer to receive the applied timing block (skip with NULL).

Returns

ra8_err_t error code.

Return values

k_ra8_ok	Timing applied.
k_ra8_err_invalid_arg	rate_mbps outside 80..720 or mode outside the enum.
k_ra8_err_not_supported	PCLKA does not match any table row.

Precondition

Module-stop is cleared.

Postcondition

DPHYTIM1..6 hold the looked-up values.

Note

Thread safety: not thread-safe.

Since

0.1.0

Definition at line 900 of file ra8_mipi_phy_timing.c.

References internal_mipi_phy_lookup_timing(), k_ra8_err_invalid_arg, k_ra8_err_not_supported, k_ra8_mipi_phy_line_rate_max_mbps, k_ra8_mipi_phy_line_rate_min_mbps, k_ra8_mipi_phy_mode_csi_device, k_ra8_mipi_phy_mode_dsi_host, k_ra8_ok, priv_mipi_phy_write_timing(), s_csi_table, and s_dsi_table.

Variable Documentation

s_csi_table

const mipi_phy_table_row_t s_csi_table[]

static

HUM Table 64.3 D-PHY timing setting CSI mode (p 3835-3836).

CSI rows only constrain TINIT, TCLKMISS, TCLKSETT, THSSETT, TCLKPREP, THSPREP – the high-speed lane fields are not used in device mode (the host side drives them). The struct fields not listed in the table are left zero-filled.

Definition at line 734 of file ra8_mipi_phy_timing.c.

Referenced by ra8_mipi_phy_select_timing().

s_dsi_table

const mipi_phy_table_row_t s_dsi_table[]

static

HUM Table 64.2 D-PHY timing setting DSI mode (p 3831-3834).

Rows are ordered by (PCLKA descending, rate ascending). Lookup picks the row with matching PCLKA whose rate_max is the smallest value >= the requested rate.

Definition at line 98 of file ra8_mipi_phy_timing.c.

Referenced by ra8_mipi_phy_select_timing().