Re: [PATCH v2 11/18] media: rzg2l-cru: Add register mapping support

Tommaso Merciai
2025-02-25T11:22:17Z

On Mon, Feb 24, 2025 at 08:44:16PM +0200, Laurent Pinchart wrote:
> On Mon, Feb 24, 2025 at 02:46:24PM +0100, Tommaso Merciai wrote:
> > On Sun, Feb 23, 2025 at 09:52:32PM +0200, Laurent Pinchart wrote:
> > > On Fri, Feb 21, 2025 at 04:55:25PM +0100, Tommaso Merciai wrote:
> > > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > >
> > > > Prepare for adding support for RZ/G3E and RZ/V2HP SoCs, which have a
> > > > CRU-IP that is mostly identical to RZ/G2L but with different register
> > > > offsets and additional registers. Introduce a flexible register mapping
> > > > mechanism to handle these variations.
> > > >
> > > > Define the `rzg2l_cru_info` structure to store register mappings and
> > > > pass it as part of the OF match data. Update the read/write functions
> > > > to use indexed register offsets from `rzg2l_cru_info`, ensuring
> > > > compatibility across different SoC variants.
> > > >
> > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> > > > Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
> > > > ---
> > > > .../platform/renesas/rzg2l-cru/rzg2l-core.c | 46 ++++++++++++-
> > > > .../renesas/rzg2l-cru/rzg2l-cru-regs.h | 65 ++++++++++---------
> > > > .../platform/renesas/rzg2l-cru/rzg2l-cru.h | 4 ++
> > > > .../platform/renesas/rzg2l-cru/rzg2l-video.c | 12 ++--
> > > > 4 files changed, 92 insertions(+), 35 deletions(-)
> > > >
> > > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c
> > > > index eed9d2bd0841..abc2a979833a 100644
> > > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c
> > > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c
> > > > @@ -22,6 +22,7 @@
> > > > #include <media/v4l2-mc.h>
> > > >
> > > > #include "rzg2l-cru.h"
> > > > +#include "rzg2l-cru-regs.h"
> > > >
> > > > static inline struct rzg2l_cru_dev *notifier_to_cru(struct v4l2_async_notifier *n)
> > > > {
> > > > @@ -269,6 +270,9 @@ static int rzg2l_cru_probe(struct platform_device *pdev)
> > > >
> > > > cru->dev = dev;
> > > > cru->info = of_device_get_match_data(dev);
> > > > + if (!cru->info)
> > > > + return dev_err_probe(dev, -EINVAL,
> > > > + "Failed to get OF match data\n");
> > > >
> > > > irq = platform_get_irq(pdev, 0);
> > > > if (irq < 0)
> > > > @@ -317,8 +321,48 @@ static void rzg2l_cru_remove(struct platform_device *pdev)
> > > > rzg2l_cru_dma_unregister(cru);
> > > > }
> > > >
> > > > +static const u16 rzg2l_cru_regs[] = {
> > > > + [CRUnCTRL] = 0x0,
> > > > + [CRUnIE] = 0x4,
> > > > + [CRUnINTS] = 0x8,
> > > > + [CRUnRST] = 0xc,
> > > > + [AMnMB1ADDRL] = 0x100,
> > > > + [AMnMB1ADDRH] = 0x104,
> > > > + [AMnMB2ADDRL] = 0x108,
> > > > + [AMnMB2ADDRH] = 0x10c,
> > > > + [AMnMB3ADDRL] = 0x110,
> > > > + [AMnMB3ADDRH] = 0x114,
> > > > + [AMnMB4ADDRL] = 0x118,
> > > > + [AMnMB4ADDRH] = 0x11c,
> > > > + [AMnMB5ADDRL] = 0x120,
> > > > + [AMnMB5ADDRH] = 0x124,
> > > > + [AMnMB6ADDRL] = 0x128,
> > > > + [AMnMB6ADDRH] = 0x12c,
> > > > + [AMnMB7ADDRL] = 0x130,
> > > > + [AMnMB7ADDRH] = 0x134,
> > > > + [AMnMB8ADDRL] = 0x138,
> > > > + [AMnMB8ADDRH] = 0x13c,
> > > > + [AMnMBVALID] = 0x148,
> > > > + [AMnMBS] = 0x14c,
> > > > + [AMnAXIATTR] = 0x158,
> > > > + [AMnFIFOPNTR] = 0x168,
> > > > + [AMnAXISTP] = 0x174,
> > > > + [AMnAXISTPACK] = 0x178,
> > > > + [ICnEN] = 0x200,
> > > > + [ICnMC] = 0x208,
> > > > + [ICnMS] = 0x254,
> > > > + [ICnDMR] = 0x26c,
> > > > +};
> > > > +
> > > > +static const struct rzg2l_cru_info rzgl2_cru_info = {
> > > > + .regs = rzg2l_cru_regs,
> > > > +};
> > > > +
> > > > static const struct of_device_id rzg2l_cru_of_id_table[] = {
> > > > - { .compatible = "renesas,rzg2l-cru", },
> > > > + {
> > > > + .compatible = "renesas,rzg2l-cru",
> > > > + .data = &rzgl2_cru_info,
> > > > + },
> > > > { /* sentinel */ }
> > > > };
> > > > MODULE_DEVICE_TABLE(of, rzg2l_cru_of_id_table);
> > > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru-regs.h b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru-regs.h
> > > > index 1c9f22118a5d..82920db7134e 100644
> > > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru-regs.h
> > > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru-regs.h
> > > > @@ -10,71 +10,76 @@
> > > >
> > > > /* HW CRU Registers Definition */
> > > >
> > > > -/* CRU Control Register */
> > > > -#define CRUnCTRL 0x0
> > > > #define CRUnCTRL_VINSEL(x) ((x) << 0)
> > > >
> > > > -/* CRU Interrupt Enable Register */
> > > > -#define CRUnIE 0x4
> > > > #define CRUnIE_EFE BIT(17)
> > > >
> > > > -/* CRU Interrupt Status Register */
> > > > -#define CRUnINTS 0x8
> > > > #define CRUnINTS_SFS BIT(16)
> > > >
> > > > -/* CRU Reset Register */
> > > > -#define CRUnRST 0xc
> > > > #define CRUnRST_VRESETN BIT(0)
> > > >
> > > > /* Memory Bank Base Address (Lower) Register for CRU Image Data */
> > > > -#define AMnMBxADDRL(x) (0x100 + ((x) * 8))
> > > > +#define AMnMBxADDRL(base, x) ((base) + (x) * 2)
> > > >
> > > > /* Memory Bank Base Address (Higher) Register for CRU Image Data */
> > > > -#define AMnMBxADDRH(x) (0x104 + ((x) * 8))
> > > > +#define AMnMBxADDRH(base, x) AMnMBxADDRL(base, x)
> > > >
> > > > -/* Memory Bank Enable Register for CRU Image Data */
> > > > -#define AMnMBVALID 0x148
> > > > #define AMnMBVALID_MBVALID(x) GENMASK(x, 0)
> > > >
> > > > -/* Memory Bank Status Register for CRU Image Data */
> > > > -#define AMnMBS 0x14c
> > > > #define AMnMBS_MBSTS 0x7
> > > >
> > > > -/* AXI Master Transfer Setting Register for CRU Image Data */
> > > > -#define AMnAXIATTR 0x158
> > > > #define AMnAXIATTR_AXILEN_MASK GENMASK(3, 0)
> > > > #define AMnAXIATTR_AXILEN (0xf)
> > > >
> > > > -/* AXI Master FIFO Pointer Register for CRU Image Data */
> > > > -#define AMnFIFOPNTR 0x168
> > > > #define AMnFIFOPNTR_FIFOWPNTR GENMASK(7, 0)
> > > > #define AMnFIFOPNTR_FIFORPNTR_Y GENMASK(23, 16)
> > > >
> > > > -/* AXI Master Transfer Stop Register for CRU Image Data */
> > > > -#define AMnAXISTP 0x174
> > > > #define AMnAXISTP_AXI_STOP BIT(0)
> > > >
> > > > -/* AXI Master Transfer Stop Status Register for CRU Image Data */
> > > > -#define AMnAXISTPACK 0x178
> > > > #define AMnAXISTPACK_AXI_STOP_ACK BIT(0)
> > > >
> > > > -/* CRU Image Processing Enable Register */
> > > > -#define ICnEN 0x200
> > > > #define ICnEN_ICEN BIT(0)
> > > >
> > > > -/* CRU Image Processing Main Control Register */
> > > > -#define ICnMC 0x208
> > > > #define ICnMC_CSCTHR BIT(5)
> > > > #define ICnMC_INF(x) ((x) << 16)
> > > > #define ICnMC_VCSEL(x) ((x) << 22)
> > > > #define ICnMC_INF_MASK GENMASK(21, 16)
> > > >
> > > > -/* CRU Module Status Register */
> > > > -#define ICnMS 0x254
> > > > #define ICnMS_IA BIT(2)
> > > >
> > > > -/* CRU Data Output Mode Register */
> > > > -#define ICnDMR 0x26c
> > > > #define ICnDMR_YCMODE_UYVY (1 << 4)
> > > >
> > > > +enum rzg2l_cru_common_regs {
> > > > + CRUnCTRL, /* CRU Control */
> > > > + CRUnIE, /* CRU Interrupt Enable */
> > > > + CRUnINTS, /* CRU Interrupt Status */
> > > > + CRUnRST, /* CRU Reset */
> > > > + AMnMB1ADDRL, /* Bank 1 Address (Lower) for CRU Image Data */
> > > > + AMnMB1ADDRH, /* Bank 1 Address (Higher) for CRU Image Data */
> > > > + AMnMB2ADDRL, /* Bank 2 Address (Lower) for CRU Image Data */
> > > > + AMnMB2ADDRH, /* Bank 2 Address (Higher) for CRU Image Data */
> > > > + AMnMB3ADDRL, /* Bank 3 Address (Lower) for CRU Image Data */
> > > > + AMnMB3ADDRH, /* Bank 3 Address (Higher) for CRU Image Data */
> > > > + AMnMB4ADDRL, /* Bank 4 Address (Lower) for CRU Image Data */
> > > > + AMnMB4ADDRH, /* Bank 4 Address (Higher) for CRU Image Data */
> > > > + AMnMB5ADDRL, /* Bank 5 Address (Lower) for CRU Image Data */
> > > > + AMnMB5ADDRH, /* Bank 5 Address (Higher) for CRU Image Data */
> > > > + AMnMB6ADDRL, /* Bank 6 Address (Lower) for CRU Image Data */
> > > > + AMnMB6ADDRH, /* Bank 6 Address (Higher) for CRU Image Data */
> > > > + AMnMB7ADDRL, /* Bank 7 Address (Lower) for CRU Image Data */
> > > > + AMnMB7ADDRH, /* Bank 7 Address (Higher) for CRU Image Data */
> > > > + AMnMB8ADDRL, /* Bank 8 Address (Lower) for CRU Image Data */
> > > > + AMnMB8ADDRH, /* Bank 8 Address (Higher) for CRU Image Data */
> > > > + AMnMBVALID, /* Memory Bank Enable for CRU Image Data */
> > > > + AMnMBS, /* Memory Bank Status for CRU Image Data */
> > > > + AMnAXIATTR, /* AXI Master Transfer Setting Register for CRU Image Data */
> > > > + AMnFIFOPNTR, /* AXI Master FIFO Pointer for CRU Image Data */
> > > > + AMnAXISTP, /* AXI Master Transfer Stop for CRU Image Data */
> > > > + AMnAXISTPACK, /* AXI Master Transfer Stop Status for CRU Image Data */
> > > > + ICnEN, /* CRU Image Processing Enable */
> > > > + ICnMC, /* CRU Image Processing Main Control */
> > > > + ICnMS, /* CRU Module Status */
> > > > + ICnDMR, /* CRU Data Output Mode */
> > > > +};
> > > > +
> > > > #endif /* __RZG2L_CRU_REGS_H__ */
> > > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
> > > > index 8b898ce05b84..00c3f7458e20 100644
> > > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
> > > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
> > > > @@ -80,6 +80,10 @@ struct rzg2l_cru_ip_format {
> > > > bool yuv;
> > > > };
> > > >
> > > > +struct rzg2l_cru_info {
> > > > + const u16 *regs;
> > > > +};
> > > > +
> > > > /**
> > > > * struct rzg2l_cru_dev - Renesas CRU device structure
> > > > * @dev: (OF) device
> > > > diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> > > > index cd69c8a686d3..f25fd9b35c55 100644
> > > > --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> > > > +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> > > > @@ -44,12 +44,16 @@ struct rzg2l_cru_buffer {
> > > > */
> > > > static void rzg2l_cru_write(struct rzg2l_cru_dev *cru, u32 offset, u32 value)
> > > > {
> > > > - iowrite32(value, cru->base + offset);
> > > > + const u16 *regs = cru->info->regs;
> > > > +
> > > > + iowrite32(value, cru->base + regs[offset]);
> > >
> > > Should out-of-bound accesses be checked ? Ideally that should be done at
> > > build time, but in some cases that may be hard. Maybe rzg2l_cru_write()
> > > and rzg2l_cru_read() could implement compile-time checks, and
> > > __rzg2l_cru_write() and __rzg2l_cru_read() could be used for the cases
> > > where checks are not possible at compile time (for AMnMBxADDRL and
> > > AMnMBxADDRH as far as I can see).
> >
> > What about using:
> >
> > static void __rzg2l_cru_write(struct rzg2l_cru_dev *cru, u32 offset, u32 value)
> > {
> > const u16 *regs = cru->info->regs;
> >
> > if (WARN_ON(offset >= RZG2L_CRU_MAX_REG) ||
> > WARN_ON(offset != CRUnCTRL && regs[offset] == 0))
> > return;
> >
> > iowrite32(value, cru->base + regs[offset]);
> > }
> >
> > static u32 __rzg2l_cru_read(struct rzg2l_cru_dev *cru, u32 offset)
> > {
> > const u16 *regs = cru->info->regs;
> >
> > if (WARN_ON(offset >= RZG2L_CRU_MAX_REG) ||
> > WARN_ON(offset != CRUnCTRL && regs[offset] == 0))
> > return 0;
> >
> > return ioread32(cru->base + regs[offset]);
> > }
> >
> > static inline void rzg2l_cru_write(struct rzg2l_cru_dev *cru, u32 offset, u32 value)
> > {
> > BUILD_BUG_ON(offset >= RZG2L_CRU_MAX_REG);
> > __rzg2l_cru_write(cru, offset, value);
>
> If there's already a check at compile time, we shouldn't incur a
> performance impact at runtime. I'd do
>
> iowrite32(value, cru->base + cru->info->regs[offset]);
>
> here. Same below.

Got it, thank.
Will update that in v3.

>
> > }
> >
> > static u32 rzg2l_cru_read(struct rzg2l_cru_dev *cru, u32 offset)
> > {
> > BUILD_BUG_ON(offset >= RZG2L_CRU_MAX_REG);
> > return __rzg2l_cru_read(cru, offset);
> > }
> >
> > And use rzg2l_cru_write, rzg2l_cru_read where check can be done at build
> > time, and __read/__write functions where check can be only done at
> > runtime.
>
> Is there a way we could use a common macro (e.g. rzg2l_cru_write()) and
> use __builtin_constant_p() to dispatch to __rzg2l_cru_write_constant()
> or __rzg2l_cru_write() ?

As you suggested I'm going to use:

#define rzg2l_cru_write(cru, offset, value) \
(__builtin_constant_p(offset) ? \
__rzg2l_cru_write_constant(cru, offset, value) : \
__rzg2l_cru_write(cru, offset, value))

#define rzg2l_cru_read(cru, offset) \
(__builtin_constant_p(offset) ? \
__rzg2l_cru_read_constant(cru, offset) : \
__rzg2l_cru_read(cru, offset))

In v3, thanks.

>
> > > > }
> > > >
> > > > static u32 rzg2l_cru_read(struct rzg2l_cru_dev *cru, u32 offset)
> > > > {
> > > > - return ioread32(cru->base + offset);
> > > > + const u16 *regs = cru->info->regs;
> > > > +
> > > > + return ioread32(cru->base + regs[offset]);
> > > > }
> > > >
> > > > /* Need to hold qlock before calling */
> > > > @@ -132,8 +136,8 @@ static void rzg2l_cru_set_slot_addr(struct rzg2l_cru_dev *cru,
> > > > return;
> > > >
> > > > /* Currently, we just use the buffer in 32 bits address */
> > > > - rzg2l_cru_write(cru, AMnMBxADDRL(slot), addr);
> > > > - rzg2l_cru_write(cru, AMnMBxADDRH(slot), 0);
> > > > + rzg2l_cru_write(cru, AMnMBxADDRL(AMnMB1ADDRL, slot), addr);
> > > > + rzg2l_cru_write(cru, AMnMBxADDRH(AMnMB1ADDRH, slot), 0);
> > >
> > > This seems fairly error-prone. The first argument doesn't seem to be
> > > needed.
> >
> > Sorry I don't completely got this.
> > Please correct me if I'm wrong.
> >
> > I think cru argument is needed here has AMnMBxADDRH macro is returning an
> > index of rzg2l_cru_regs[] and not the real address.
>
> I meant the first argument to the AMnMBxADDRL() and AMnMBxADDRH(),
> sorry. Can it ever be something else than AMnMB1ADDRL or AMnMB1ADDRH
> respectively ?

Agree we can just use:

#define AMnMBxADDRL(x) (AMnMB1ADDRL + (x) * 2)
#define AMnMBxADDRH(x) (AMnMB1ADDRH + (x) * 2)

Will use this in v3.
Thanks.

>
> > Btw with the changes above here we can use:
> >
> > __rzg2l_cru_write(cru, AMnMBxADDRL(AMnMB1ADDRL, slot), addr);
> > __rzg2l_cru_write(cru, AMnMBxADDRH(AMnMB1ADDRH, slot), 0);
> >
> > That is checking for out-of-bound accesses at runtime.
> >
> > What do you think?
> > Thanks in advance.
> >
> > > > }
> > > >
> > > > /*
>
> --
> Regards,
>
> Laurent Pinchart

Regards,
Tommaso