On Fri, Feb 16, 2024 at 02:45:14PM +0100, Niklas Cassel wrote:
> The hardware description for BARs is scattered in many different variables
> in pci_epc_features. Some of these things are mutually exclusive, so it
> can create confusion over which variable that has precedence over another.
>
> Improve the situation by creating a struct pci_epc_bar_desc, and a new
> enum pci_epc_bar_type, and convert the endpoint controller drivers to use
> this more well defined format.
>
> Additionally, some endpoint controller drivers mark the BAR succeeding a
> "64-bit only BAR" as reserved, while some do not. By definition, a 64-bit
> BAR uses the succeeding BAR for the upper 32-bits, so an EPF driver cannot
> use a BAR succeeding a 64-bit BAR. Ensure that all endpoint controller
> drivers are uniform, and actually describe a reserved BAR as reserved.
>
> Signed-off-by: Niklas Cassel <cas...@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasi...@linaro.org>
- Mani
> Reviewed-by: Kishon Vijay Abraham I <kis...@kernel.org>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 3 +-
> drivers/pci/controller/dwc/pci-keystone.c | 12 +++----
> .../pci/controller/dwc/pci-layerscape-ep.c | 5 ++-
> drivers/pci/controller/dwc/pcie-keembay.c | 8 +++--
> drivers/pci/controller/dwc/pcie-rcar-gen4.c | 4 ++-
> drivers/pci/controller/dwc/pcie-tegra194.c | 10 ++++--
> drivers/pci/controller/dwc/pcie-uniphier-ep.c | 15 ++++++--
> drivers/pci/controller/pcie-rcar-ep.c | 14 +++++---
> drivers/pci/endpoint/functions/pci-epf-ntb.c | 4 +--
> drivers/pci/endpoint/functions/pci-epf-test.c | 8 ++---
> drivers/pci/endpoint/functions/pci-epf-vntb.c | 2 +-
> drivers/pci/endpoint/pci-epc-core.c | 32 +++++++++--------
> drivers/pci/endpoint/pci-epf-core.c | 15 ++++----
> include/linux/pci-epc.h | 34 +++++++++++++++----
> 14 files changed, 108 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> b/drivers/pci/controller/dwc/pci-imx6.c
> index dc2c036ab28c..47a9a96484ed 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1081,7 +1081,8 @@ static const struct pci_epc_features
> imx8m_pcie_epc_features = {
> .linkup_notifier = false,
> .msi_capable = true,
> .msix_capable = false,
> - .reserved_bar = 1 << BAR_1 | 1 << BAR_3,
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> .align = SZ_64K,
> };
>
> diff --git a/drivers/pci/controller/dwc/pci-keystone.c
> b/drivers/pci/controller/dwc/pci-keystone.c
> index c0c62533a3f1..b2b93b4fa82d 100644
> --- a/drivers/pci/controller/dwc/pci-keystone.c
> +++ b/drivers/pci/controller/dwc/pci-keystone.c
> @@ -924,12 +924,12 @@ static const struct pci_epc_features
> ks_pcie_am654_epc_features = {
> .linkup_notifier = false,
> .msi_capable = true,
> .msix_capable = true,
> - .reserved_bar = 1 << BAR_0 | 1 << BAR_1,
> - .bar_fixed_64bit = 1 << BAR_0,
> - .bar_fixed_size[2] = SZ_1M,
> - .bar_fixed_size[3] = SZ_64K,
> - .bar_fixed_size[4] = 256,
> - .bar_fixed_size[5] = SZ_1M,
> + .bar[BAR_0] = { .type = BAR_RESERVED, .only_64bit = true, },
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_2] = { .type = BAR_FIXED, .fixed_size = SZ_1M, },
> + .bar[BAR_3] = { .type = BAR_FIXED, .fixed_size = SZ_64K, },
> + .bar[BAR_4] = { .type = BAR_FIXED, .fixed_size = 256, },
> + .bar[BAR_5] = { .type = BAR_FIXED, .fixed_size = SZ_1M, },
> .align = SZ_1M,
> };
>
> diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> index 2e398494e7c0..1f6ee1460ec2 100644
> --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> @@ -250,7 +250,10 @@ static int __init ls_pcie_ep_probe(struct
> platform_device *pdev)
> pci->dev = dev;
> pci->ops = pcie->drvdata->dw_pcie_ops;
>
> - ls_epc->bar_fixed_64bit = (1 << BAR_2) | (1 << BAR_4);
> + ls_epc->bar[BAR_2].only_64bit = true;
> + ls_epc->bar[BAR_3].type = BAR_RESERVED;
> + ls_epc->bar[BAR_4].only_64bit = true;
> + ls_epc->bar[BAR_5].type = BAR_RESERVED;
> ls_epc->linkup_notifier = true;
>
> pcie->pci = pci;
> diff --git a/drivers/pci/controller/dwc/pcie-keembay.c
> b/drivers/pci/controller/dwc/pcie-keembay.c
> index 208d3b0ba196..5e8e54f597dd 100644
> --- a/drivers/pci/controller/dwc/pcie-keembay.c
> +++ b/drivers/pci/controller/dwc/pcie-keembay.c
> @@ -312,8 +312,12 @@ static const struct pci_epc_features
> keembay_pcie_epc_features = {
> .linkup_notifier = false,
> .msi_capable = true,
> .msix_capable = true,
> - .reserved_bar = BIT(BAR_1) | BIT(BAR_3) | BIT(BAR_5),
> - .bar_fixed_64bit = BIT(BAR_0) | BIT(BAR_2) | BIT(BAR_4),
> + .bar[BAR_0] = { .only_64bit = true, },
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_2] = { .only_64bit = true, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> + .bar[BAR_4] = { .only_64bit = true, },
> + .bar[BAR_5] = { .type = BAR_RESERVED, },
> .align = SZ_16K,
> };
>
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index e9166619b1f9..0be760ed420b 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -383,7 +383,9 @@ static const struct pci_epc_features
> rcar_gen4_pcie_epc_features = {
> .linkup_notifier = false,
> .msi_capable = true,
> .msix_capable = false,
> - .reserved_bar = 1 << BAR_1 | 1 << BAR_3 | 1 << BAR_5,
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> + .bar[BAR_5] = { .type = BAR_RESERVED, },
> .align = SZ_1M,
> };
>
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c
> b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 7afa9e9aabe2..1f7b662cb8e1 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -2007,9 +2007,13 @@ static const struct pci_epc_features
> tegra_pcie_epc_features = {
> .core_init_notifier = true,
> .msi_capable = false,
> .msix_capable = false,
> - .reserved_bar = 1 << BAR_2 | 1 << BAR_3 | 1 << BAR_4 | 1 << BAR_5,
> - .bar_fixed_64bit = 1 << BAR_0,
> - .bar_fixed_size[0] = SZ_1M,
> + .bar[BAR_0] = { .type = BAR_FIXED, .fixed_size = SZ_1M,
> + .only_64bit = true, },
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_2] = { .type = BAR_RESERVED, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> + .bar[BAR_4] = { .type = BAR_RESERVED, },
> + .bar[BAR_5] = { .type = BAR_RESERVED, },
> };
>
> static const struct pci_epc_features*
> diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> index 3fced0d3e851..265f65fc673f 100644
> --- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> @@ -411,8 +411,12 @@ static const struct uniphier_pcie_ep_soc_data
> uniphier_pro5_data = {
> .msi_capable = true,
> .msix_capable = false,
> .align = 1 << 16,
> - .bar_fixed_64bit = BIT(BAR_0) | BIT(BAR_2) | BIT(BAR_4),
> - .reserved_bar = BIT(BAR_4),
> + .bar[BAR_0] = { .only_64bit = true, },
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_2] = { .only_64bit = true, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> + .bar[BAR_4] = { .type = BAR_RESERVED, .only_64bit = true, },
> + .bar[BAR_5] = { .type = BAR_RESERVED, },
> },
> };
>
> @@ -425,7 +429,12 @@ static const struct uniphier_pcie_ep_soc_data
> uniphier_nx1_data = {
> .msi_capable = true,
> .msix_capable = false,
> .align = 1 << 12,
> - .bar_fixed_64bit = BIT(BAR_0) | BIT(BAR_2) | BIT(BAR_4),
> + .bar[BAR_0] = { .only_64bit = true, },
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_2] = { .only_64bit = true, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> + .bar[BAR_4] = { .only_64bit = true, },
> + .bar[BAR_5] = { .type = BAR_RESERVED, },
> },
> };
>
> diff --git a/drivers/pci/controller/pcie-rcar-ep.c
> b/drivers/pci/controller/pcie-rcar-ep.c
> index e6909271def7..05967c6c0b42 100644
> --- a/drivers/pci/controller/pcie-rcar-ep.c
> +++ b/drivers/pci/controller/pcie-rcar-ep.c
> @@ -440,11 +440,15 @@ static const struct pci_epc_features
> rcar_pcie_epc_features = {
> .msi_capable = true,
> .msix_capable = false,
> /* use 64-bit BARs so mark BAR[1,3,5] as reserved */
> - .reserved_bar = 1 << BAR_1 | 1 << BAR_3 | 1 << BAR_5,
> - .bar_fixed_64bit = 1 << BAR_0 | 1 << BAR_2 | 1 << BAR_4,
> - .bar_fixed_size[0] = 128,
> - .bar_fixed_size[2] = 256,
> - .bar_fixed_size[4] = 256,
> + .bar[BAR_0] = { .type = BAR_FIXED, .fixed_size = 128,
> + .only_64bit = true, },
> + .bar[BAR_1] = { .type = BAR_RESERVED, },
> + .bar[BAR_2] = { .type = BAR_FIXED, .fixed_size = 256,
> + .only_64bit = true, },
> + .bar[BAR_3] = { .type = BAR_RESERVED, },
> + .bar[BAR_4] = { .type = BAR_FIXED, .fixed_size = 256,
> + .only_64bit = true, },
> + .bar[BAR_5] = { .type = BAR_RESERVED, },
> };
>
> static const struct pci_epc_features*
> diff --git a/drivers/pci/endpoint/functions/pci-epf-ntb.c
> b/drivers/pci/endpoint/functions/pci-epf-ntb.c
> index 43cd309ce22f..e01a98e74d21 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-ntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-ntb.c
> @@ -1012,13 +1012,13 @@ static int epf_ntb_config_spad_bar_alloc(struct
> epf_ntb *ntb,
>
> epc_features = ntb_epc->epc_features;
> barno = ntb_epc->epf_ntb_bar[BAR_CONFIG];
> - size = epc_features->bar_fixed_size[barno];
> + size = epc_features->bar[barno].fixed_size;
> align = epc_features->align;
>
> peer_ntb_epc = ntb->epc[!type];
> peer_epc_features = peer_ntb_epc->epc_features;
> peer_barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD];
> - peer_size = peer_epc_features->bar_fixed_size[peer_barno];
> + peer_size = peer_epc_features->bar[peer_barno].fixed_size;
>
> /* Check if epc_features is populated incorrectly */
> if ((!IS_ALIGNED(size, align)))
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c
> b/drivers/pci/endpoint/functions/pci-epf-test.c
> index 981894e40681..cd4ffb39dcdc 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -729,7 +729,7 @@ static int pci_epf_test_set_bar(struct pci_epf *epf)
> */
> add = (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ? 2 : 1;
>
> - if (!!(epc_features->reserved_bar & (1 << bar)))
> + if (epc_features->bar[bar].type == BAR_RESERVED)
> continue;
>
> ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no,
> @@ -856,7 +856,7 @@ static int pci_epf_test_alloc_space(struct pci_epf *epf)
> if (bar == test_reg_bar)
> continue;
>
> - if (!!(epc_features->reserved_bar & (1 << bar)))
> + if (epc_features->bar[bar].type == BAR_RESERVED)
> continue;
>
> base = pci_epf_alloc_space(epf, bar_size[bar], bar,
> @@ -874,13 +874,11 @@ static void pci_epf_configure_bar(struct pci_epf *epf,
> const struct pci_epc_features *epc_features)
> {
> struct pci_epf_bar *epf_bar;
> - bool bar_fixed_64bit;
> int i;
>
> for (i = 0; i < PCI_STD_NUM_BARS; i++) {
> epf_bar = &epf->bar[i];
> - bar_fixed_64bit = !!(epc_features->bar_fixed_64bit & (1 << i));
> - if (bar_fixed_64bit)
> + if (epc_features->bar[i].only_64bit)
> epf_bar->flags |= PCI_BASE_ADDRESS_MEM_TYPE_64;
> }
> }
> diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> index 0675929fc529..8e779eecd62d 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
> @@ -422,7 +422,7 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb
> *ntb)
> epf->func_no,
> epf->vfunc_no);
> barno = ntb->epf_ntb_bar[BAR_CONFIG];
> - size = epc_features->bar_fixed_size[barno];
> + size = epc_features->bar[barno].fixed_size;
> align = epc_features->align;
>
> if ((!IS_ALIGNED(size, align)))
> diff --git a/drivers/pci/endpoint/pci-epc-core.c
> b/drivers/pci/endpoint/pci-epc-core.c
> index dcd4e66430c1..7fe8f4336765 100644
> --- a/drivers/pci/endpoint/pci-epc-core.c
> +++ b/drivers/pci/endpoint/pci-epc-core.c
> @@ -87,7 +87,7 @@ EXPORT_SYMBOL_GPL(pci_epc_get);
> * @epc_features: pci_epc_features structure that holds the reserved bar
> bitmap
> *
> * Invoke to get the first unreserved BAR that can be used by the endpoint
> - * function. For any incorrect value in reserved_bar return '0'.
> + * function.
> */
> enum pci_barno
> pci_epc_get_first_free_bar(const struct pci_epc_features *epc_features)
> @@ -102,32 +102,34 @@ EXPORT_SYMBOL_GPL(pci_epc_get_first_free_bar);
> * @bar: the starting BAR number from where unreserved BAR should be searched
> *
> * Invoke to get the next unreserved BAR starting from @bar that can be used
> - * for endpoint function. For any incorrect value in reserved_bar return '0'.
> + * for endpoint function.
> */
> enum pci_barno pci_epc_get_next_free_bar(const struct pci_epc_features
> *epc_features, enum pci_barno bar)
> {
> - unsigned long free_bar;
> + int i;
>
> if (!epc_features)
> return BAR_0;
>
> /* If 'bar - 1' is a 64-bit BAR, move to the next BAR */
> - if ((epc_features->bar_fixed_64bit << 1) & 1 << bar)
> + if (bar > 0 && epc_features->bar[bar - 1].only_64bit)
> bar++;
>
> - /* Find if the reserved BAR is also a 64-bit BAR */
> - free_bar = epc_features->reserved_bar & epc_features->bar_fixed_64bit;
> -
> - /* Set the adjacent bit if the reserved BAR is also a 64-bit BAR */
> - free_bar <<= 1;
> - free_bar |= epc_features->reserved_bar;
> -
> - free_bar = find_next_zero_bit(&free_bar, 6, bar);
> - if (free_bar > 5)
> - return NO_BAR;
> + for (i = bar; i < PCI_STD_NUM_BARS; i++) {
> + /* If the BAR is not reserved, return it. */
> + if (epc_features->bar[i].type != BAR_RESERVED)
> + return i;
> +
> + /*
> + * If the BAR is reserved, and marked as 64-bit only, then the
> + * succeeding BAR is also reserved.
> + */
> + if (epc_features->bar[i].only_64bit)
> + i++;
> + }
>
> - return free_bar;
> + return NO_BAR;
> }
> EXPORT_SYMBOL_GPL(pci_epc_get_next_free_bar);
>
> diff --git a/drivers/pci/endpoint/pci-epf-core.c
> b/drivers/pci/endpoint/pci-epf-core.c
> index f2b4d34454c4..0a28a0b0911b 100644
> --- a/drivers/pci/endpoint/pci-epf-core.c
> +++ b/drivers/pci/endpoint/pci-epf-core.c
> @@ -260,7 +260,7 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t
> size, enum pci_barno bar,
> const struct pci_epc_features *epc_features,
> enum pci_epc_interface_type type)
> {
> - u64 bar_fixed_size = epc_features->bar_fixed_size[bar];
> + u64 bar_fixed_size = epc_features->bar[bar].fixed_size;
> size_t align = epc_features->align;
> struct pci_epf_bar *epf_bar;
> dma_addr_t phys_addr;
> @@ -271,13 +271,14 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t
> size, enum pci_barno bar,
> if (size < 128)
> size = 128;
>
> - if (bar_fixed_size && size > bar_fixed_size) {
> - dev_err(&epf->dev, "requested BAR size is larger than fixed
> size\n");
> - return NULL;
> - }
> -
> - if (bar_fixed_size)
> + if (epc_features->bar[bar].type == BAR_FIXED && bar_fixed_size) {
> + if (size > bar_fixed_size) {
> + dev_err(&epf->dev,
> + "requested BAR size is larger than fixed
> size\n");
> + return NULL;
> + }
> size = bar_fixed_size;
> + }
>
> if (align)
> size = ALIGN(size, align);
> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
> index 40ea18f5aa02..4ccb4f4f3883 100644
> --- a/include/linux/pci-epc.h
> +++ b/include/linux/pci-epc.h
> @@ -145,6 +145,32 @@ struct pci_epc {
> unsigned long function_num_map;
> };
>
> +/**
> + * @BAR_PROGRAMMABLE: The BAR mask can be configured by the EPC.
> + * @BAR_FIXED: The BAR mask is fixed by the hardware.
> + * @BAR_RESERVED: The BAR should not be touched by an EPF driver.
> + */
> +enum pci_epc_bar_type {
> + BAR_PROGRAMMABLE = 0,
> + BAR_FIXED,
> + BAR_RESERVED,
> +};
> +
> +/**
> + * struct pci_epc_bar_desc - hardware description for a BAR
> + * @type: the type of the BAR
> + * @fixed_size: the fixed size, only applicable if type is BAR_FIXED_MASK.
> + * @only_64bit: if true, an EPF driver is not allowed to choose if this BAR
> + * should be configured as 32-bit or 64-bit, the EPF driver must
> + * configure this BAR as 64-bit. Additionally, the BAR succeeding
> + * this BAR must be set to type BAR_RESERVED.
> + */
> +struct pci_epc_bar_desc {
> + enum pci_epc_bar_type type;
> + u64 fixed_size;
> + bool only_64bit;
> +};
> +
> /**
> * struct pci_epc_features - features supported by a EPC device per function
> * @linkup_notifier: indicate if the EPC device can notify EPF driver on
> link up
> @@ -152,9 +178,7 @@ struct pci_epc {
> * for initialization
> * @msi_capable: indicate if the endpoint function has MSI capability
> * @msix_capable: indicate if the endpoint function has MSI-X capability
> - * @reserved_bar: bitmap to indicate reserved BAR unavailable to function
> driver
> - * @bar_fixed_64bit: bitmap to indicate fixed 64bit BARs
> - * @bar_fixed_size: Array specifying the size supported by each BAR
> + * @bar: array specifying the hardware description for each BAR
> * @align: alignment size required for BAR buffer allocation
> */
> struct pci_epc_features {
> @@ -162,9 +186,7 @@ struct pci_epc_features {
> unsigned int core_init_notifier : 1;
> unsigned int msi_capable : 1;
> unsigned int msix_capable : 1;
> - u8 reserved_bar;
> - u8 bar_fixed_64bit;
> - u64 bar_fixed_size[PCI_STD_NUM_BARS];
> + struct pci_epc_bar_desc bar[PCI_STD_NUM_BARS];
> size_t align;
> };
>
> --
> 2.43.1
>
--
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