On Sun, Nov 30, 2025 at 01:03:41AM +0900, Koichiro Den wrote:
> Add and use new fields in the common control register to convey both
> offset and size for each memory window (MW), so that it can correctly
> handle flexible MW layouts and support partial BAR mappings.
>
> Signed-off-by: Koichiro Den <den@valinux.co.jp>
> ---
> drivers/ntb/hw/epf/ntb_hw_epf.c | 27 ++++++++++++++++-----------
> 1 file changed, 16 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c b/drivers/ntb/hw/epf/ntb_hw_epf.c
> index d3ecf25a5162..91d3f8e05807 100644
> --- a/drivers/ntb/hw/epf/ntb_hw_epf.c
> +++ b/drivers/ntb/hw/epf/ntb_hw_epf.c
> @@ -36,12 +36,13 @@
> #define NTB_EPF_LOWER_SIZE 0x18
> #define NTB_EPF_UPPER_SIZE 0x1C
> #define NTB_EPF_MW_COUNT 0x20
> -#define NTB_EPF_MW1_OFFSET 0x24
> -#define NTB_EPF_SPAD_OFFSET 0x28
> -#define NTB_EPF_SPAD_COUNT 0x2C
> -#define NTB_EPF_DB_ENTRY_SIZE 0x30
> -#define NTB_EPF_DB_DATA(n) (0x34 + (n) * 4)
> -#define NTB_EPF_DB_OFFSET(n) (0xB4 + (n) * 4)
> +#define NTB_EPF_MW_OFFSET(n) (0x24 + (n) * 4)
> +#define NTB_EPF_MW_SIZE(n) (0x34 + (n) * 4)
> +#define NTB_EPF_SPAD_OFFSET 0x44
> +#define NTB_EPF_SPAD_COUNT 0x48
> +#define NTB_EPF_DB_ENTRY_SIZE 0x4C
> +#define NTB_EPF_DB_DATA(n) (0x50 + (n) * 4)
> +#define NTB_EPF_DB_OFFSET(n) (0xD0 + (n) * 4)
You need check difference version for register layout change. EP and RC
side's software are not necessary to run the same kernel. Maybe EP side
running at old version, RC side run at new version.
Frank
>
> #define NTB_EPF_MIN_DB_COUNT 3
> #define NTB_EPF_MAX_DB_COUNT 31
> @@ -451,11 +452,12 @@ static int ntb_epf_peer_mw_get_addr(struct ntb_dev *ntb, int idx,
> phys_addr_t *base, resource_size_t *size)
> {
> struct ntb_epf_dev *ndev = ntb_ndev(ntb);
> - u32 offset = 0;
> + resource_size_t bar_sz;
> + u32 offset, sz;
> int bar;
>
> - if (idx == 0)
> - offset = readl(ndev->ctrl_reg + NTB_EPF_MW1_OFFSET);
> + offset = readl(ndev->ctrl_reg + NTB_EPF_MW_OFFSET(idx));
> + sz = readl(ndev->ctrl_reg + NTB_EPF_MW_SIZE(idx));
>
> bar = ntb_epf_mw_to_bar(ndev, idx);
> if (bar < 0)
> @@ -464,8 +466,11 @@ static int ntb_epf_peer_mw_get_addr(struct ntb_dev *ntb, int idx,
> if (base)
> *base = pci_resource_start(ndev->ntb.pdev, bar) + offset;
>
> - if (size)
> - *size = pci_resource_len(ndev->ntb.pdev, bar) - offset;
> + if (size) {
> + bar_sz = pci_resource_len(ndev->ntb.pdev, bar);
> + *size = sz ? min_t(resource_size_t, sz, bar_sz - offset)
> + : (bar_sz > offset ? bar_sz - offset : 0);
> + }
>
> return 0;
> }
> --
> 2.48.1
>