drivers/gpu/drm/renesas/rcar-du/rcar_du_group.c
Source file repositories/reference/linux-study-clean/drivers/gpu/drm/renesas/rcar-du/rcar_du_group.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/gpu/drm/renesas/rcar-du/rcar_du_group.c- Extension
.c- Size
- 11760 bytes
- Lines
- 390
- Domain
- Driver Families
- Bucket
- drivers/gpu
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/clk.hlinux/io.hrcar_du_drv.hrcar_du_group.hrcar_du_regs.h
Detected Declarations
function Copyrightfunction rcar_du_group_writefunction rcar_du_group_setup_pinsfunction rcar_du_group_setup_defr8function rcar_du_group_setup_didsrfunction rcar_du_group_setupfunction rcar_du_group_getfunction rcar_du_group_putfunction __rcar_du_group_start_stopfunction rcar_du_crtc_dsysr_clr_setfunction rcar_du_group_start_stopfunction rcar_du_group_restartfunction rcar_du_set_dpad0_vsp1_routingfunction rcar_du_group_set_dpad_levelsfunction rcar_du_group_set_routing
Annotated Snippet
if (rgrp->index == 0) {
defr8 |= DEFR8_DRGBS_DU(rcdu->dpad0_source);
if (rgrp->dev->vspd1_sink == 2)
defr8 |= DEFR8_VSCS;
}
} else {
/*
* On Gen3 VSPD routing can't be configured, and DPAD routing
* is set in the group corresponding to the DPAD output (no Gen3
* SoC has multiple DPAD sources belonging to separate groups).
*/
if (rgrp->index == rcdu->dpad0_source / 2)
defr8 |= DEFR8_DRGBS_DU(rcdu->dpad0_source);
}
rcar_du_group_write(rgrp, DEFR8, defr8);
}
static void rcar_du_group_setup_didsr(struct rcar_du_group *rgrp)
{
struct rcar_du_device *rcdu = rgrp->dev;
struct rcar_du_crtc *rcrtc;
unsigned int num_crtcs = 0;
unsigned int i;
u32 didsr;
/*
* Configure input dot clock routing with a hardcoded configuration. If
* the DU channel can use the LVDS encoder output clock as the dot
* clock, do so. Otherwise route DU_DOTCLKINn signal to DUn.
*
* Each channel can then select between the dot clock configured here
* and the clock provided by the CPG through the ESCR register.
*/
if (rcdu->info->gen < 3 && rgrp->index == 0) {
/*
* On Gen2 a single register in the first group controls dot
* clock selection for all channels.
*/
rcrtc = rcdu->crtcs;
num_crtcs = rcdu->num_crtcs;
} else if ((rcdu->info->gen == 3 && rgrp->num_crtcs > 1) ||
rcdu->info->gen == 4) {
/*
* On Gen3 dot clocks are setup through per-group registers,
* only available when the group has two channels.
* On Gen4 the registers are there for single channel too.
*/
rcrtc = &rcdu->crtcs[rgrp->index * 2];
num_crtcs = rgrp->num_crtcs;
}
if (!num_crtcs)
return;
didsr = DIDSR_CODE;
for (i = 0; i < num_crtcs; ++i, ++rcrtc) {
if (rcdu->info->lvds_clk_mask & BIT(rcrtc->index))
didsr |= DIDSR_LDCS_LVDS0(i)
| DIDSR_PDCS_CLK(i, 0);
else if (rcdu->info->dsi_clk_mask & BIT(rcrtc->index))
didsr |= DIDSR_LDCS_DSI(i);
else
didsr |= DIDSR_LDCS_DCLKIN(i)
| DIDSR_PDCS_CLK(i, 0);
}
rcar_du_group_write(rgrp, DIDSR, didsr);
}
static void rcar_du_group_setup(struct rcar_du_group *rgrp)
{
struct rcar_du_device *rcdu = rgrp->dev;
u32 defr7 = DEFR7_CODE;
u32 dorcr;
/* Enable extended features */
rcar_du_group_write(rgrp, DEFR, DEFR_CODE | DEFR_DEFE);
if (rcdu->info->gen < 3) {
rcar_du_group_write(rgrp, DEFR2, DEFR2_CODE | DEFR2_DEFE2G);
rcar_du_group_write(rgrp, DEFR3, DEFR3_CODE | DEFR3_DEFE3);
rcar_du_group_write(rgrp, DEFR4, DEFR4_CODE);
}
rcar_du_group_write(rgrp, DEFR5, DEFR5_CODE | DEFR5_DEFE5);
if (rcdu->info->gen < 4)
rcar_du_group_setup_pins(rgrp);
if (rcdu->info->gen < 4) {
/*
Annotation
- Immediate include surface: `linux/clk.h`, `linux/io.h`, `rcar_du_drv.h`, `rcar_du_group.h`, `rcar_du_regs.h`.
- Detected declarations: `function Copyright`, `function rcar_du_group_write`, `function rcar_du_group_setup_pins`, `function rcar_du_group_setup_defr8`, `function rcar_du_group_setup_didsr`, `function rcar_du_group_setup`, `function rcar_du_group_get`, `function rcar_du_group_put`, `function __rcar_du_group_start_stop`, `function rcar_du_crtc_dsysr_clr_set`.
- Atlas domain: Driver Families / drivers/gpu.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.