Re: [PATCH 03/20] cxl: Move CXL spec defines to public header

[Jonathan Cameron <jonathan.cameron@huawei.com>]

On Thu, 12 Mar 2026 02:04:23 +0530
mhonap@nvidia.com wrote:

> From: Manish Honap <mhonap@nvidia.com>
> 
> HDM decoder capability structure and component reg block size
> needs to be used by VFIO subsystem. Move the macros from private
> CXL header to public one.
> 
> Signed-off-by: Manish Honap <mhonap@nvidia.com>

Not really related to this patch, but...

Maybe this is the time to think about doing a PCI like
uapi/linux/cxl_regs.h header?

So far we have these duplicated in at least a couple of code
bases and that is less than ideal!

Move seems fine to me otherwise.

> ---
>  drivers/cxl/cxl.h | 30 ------------------------------
>  include/cxl/cxl.h | 30 ++++++++++++++++++++++++++++++
>  2 files changed, 30 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 10ddab3949ee..7146059e0dae 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -24,9 +24,6 @@ extern const struct nvdimm_security_ops *cxl_security_ops;
>   * (port-driver, region-driver, nvdimm object-drivers... etc).
>   */
>  
> -/* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
> -#define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
> -
>  /* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
>  #define CXL_CM_OFFSET 0x1000
>  #define CXL_CM_CAP_HDR_OFFSET 0x0
> @@ -39,33 +36,6 @@ extern const struct nvdimm_security_ops *cxl_security_ops;
>  #define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
>  #define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
>  
> -/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
> -#define CXL_HDM_DECODER_CAP_OFFSET 0x0
> -#define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
> -#define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
> -#define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
> -#define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
> -#define   CXL_HDM_DECODER_INTERLEAVE_3_6_12_WAY BIT(11)
> -#define   CXL_HDM_DECODER_INTERLEAVE_16_WAY BIT(12)
> -#define CXL_HDM_DECODER_CTRL_OFFSET 0x4
> -#define   CXL_HDM_DECODER_ENABLE BIT(1)
> -#define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
> -#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
> -#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
> -#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
> -#define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
> -#define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
> -#define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
> -#define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
> -#define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
> -#define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
> -#define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
> -#define   CXL_HDM_DECODER0_CTRL_HOSTONLY BIT(12)
> -#define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
> -#define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
> -#define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
> -#define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
> -
>  /* HDM decoder control register constants CXL 3.0 8.2.5.19.7 */
>  #define CXL_DECODER_MIN_GRANULARITY 256
>  #define CXL_DECODER_MAX_ENCODED_IG 6
> diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
> index 610711e861d4..27c006fa53c3 100644
> --- a/include/cxl/cxl.h
> +++ b/include/cxl/cxl.h
> @@ -75,6 +75,36 @@ struct cxl_regs {
>  #define   CXL_CM_CAP_CAP_ID_HDM 0x5
>  #define   CXL_CM_CAP_CAP_HDM_VERSION 1
>  
> +/* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
> +#define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
> +
> +/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
> +#define CXL_HDM_DECODER_CAP_OFFSET 0x0
> +#define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
> +#define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
> +#define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
> +#define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
> +#define   CXL_HDM_DECODER_INTERLEAVE_3_6_12_WAY BIT(11)
> +#define   CXL_HDM_DECODER_INTERLEAVE_16_WAY BIT(12)
> +#define CXL_HDM_DECODER_CTRL_OFFSET 0x4
> +#define   CXL_HDM_DECODER_ENABLE BIT(1)
> +#define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
> +#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
> +#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
> +#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
> +#define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
> +#define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
> +#define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
> +#define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
> +#define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
> +#define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
> +#define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
> +#define   CXL_HDM_DECODER0_CTRL_HOSTONLY BIT(12)
> +#define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
> +#define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
> +#define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
> +#define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
> +
>  struct cxl_reg_map {
>  	bool valid;
>  	int id;