Re: [PATCH v4 04/10] PCI: dwc: Rework MSI callbacks handler

From: Kishon Vijay Abraham I
Date: Wed Jun 20 2018 - 05:29:20 EST


Hi,

On Monday 18 June 2018 08:30 PM, Gustavo Pimentel wrote:
> Remove duplicate defines located on pcie-designware.h file already
> available on /include/uapi/linux/pci-regs.h file.
>
> Add pci_epc_set_msi() maximum 32 interrupts validation.
>
> Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
> ---
> Change v1->v2:
> - Nothing changed, just to follow the patch set version.
> Change v2->v3:
> - Replaced wrong return value 0 to -EINVAL.
> Change v3->v4:
> - Rebased to Lorenzo's master branch v4.18-rc1.
>
> drivers/pci/controller/dwc/pcie-designware-ep.c | 49 +++++++++++++++++--------
> drivers/pci/controller/dwc/pcie-designware.h | 11 ------
> drivers/pci/endpoint/pci-epc-core.c | 3 +-
> 3 files changed, 35 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index ad25654..89d9e52 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -246,29 +246,38 @@ static int dw_pcie_ep_map_addr(struct pci_epc *epc, u8 func_no,
>
> static int dw_pcie_ep_get_msi(struct pci_epc *epc, u8 func_no)
> {
> - int val;
> struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + u32 val, reg;
> +
> + if (!ep->msi_cap)
> + return -EINVAL;
>
> - val = dw_pcie_readw_dbi(pci, MSI_MESSAGE_CONTROL);
> - if (!(val & MSI_CAP_MSI_EN_MASK))
> + reg = ep->msi_cap + PCI_MSI_FLAGS;
> + val = dw_pcie_readw_dbi(pci, reg);
> + if (!(val & PCI_MSI_FLAGS_ENABLE))
> return -EINVAL;
>
> - val = (val & MSI_CAP_MME_MASK) >> MSI_CAP_MME_SHIFT;
> + val = (val & PCI_MSI_FLAGS_QSIZE) >> 4;
> +
> return val;
> }
>
> -static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 encode_int)
> +static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 func_no, u8 interrupts)
> {
> - int val;
> struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + u32 val, reg;
>
> - val = dw_pcie_readw_dbi(pci, MSI_MESSAGE_CONTROL);
> - val &= ~MSI_CAP_MMC_MASK;
> - val |= (encode_int << MSI_CAP_MMC_SHIFT) & MSI_CAP_MMC_MASK;
> + if (!ep->msi_cap)
> + return -EINVAL;
> +
> + reg = ep->msi_cap + PCI_MSI_FLAGS;
> + val = dw_pcie_readw_dbi(pci, reg);
> + val &= ~PCI_MSI_FLAGS_QMASK;
> + val |= (interrupts << 1) & PCI_MSI_FLAGS_QMASK;
> dw_pcie_dbi_ro_wr_en(pci);
> - dw_pcie_writew_dbi(pci, MSI_MESSAGE_CONTROL, val);
> + dw_pcie_writew_dbi(pci, reg, val);
> dw_pcie_dbi_ro_wr_dis(pci);
>
> return 0;
> @@ -367,21 +376,29 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
> struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> struct pci_epc *epc = ep->epc;
> u16 msg_ctrl, msg_data;
> - u32 msg_addr_lower, msg_addr_upper;
> + u32 msg_addr_lower, msg_addr_upper, reg;
> u64 msg_addr;
> bool has_upper;
> int ret;
>
> + if (!ep->msi_cap)
> + return -EINVAL;
> +
> /* Raise MSI per the PCI Local Bus Specification Revision 3.0, 6.8.1. */
> - msg_ctrl = dw_pcie_readw_dbi(pci, MSI_MESSAGE_CONTROL);
> + reg = ep->msi_cap + PCI_MSI_FLAGS;
> + msg_ctrl = dw_pcie_readw_dbi(pci, reg);
> has_upper = !!(msg_ctrl & PCI_MSI_FLAGS_64BIT);
> - msg_addr_lower = dw_pcie_readl_dbi(pci, MSI_MESSAGE_ADDR_L32);
> + reg = ep->msi_cap + PCI_MSI_ADDRESS_LO;
> + msg_addr_lower = dw_pcie_readl_dbi(pci, reg);
> if (has_upper) {
> - msg_addr_upper = dw_pcie_readl_dbi(pci, MSI_MESSAGE_ADDR_U32);
> - msg_data = dw_pcie_readw_dbi(pci, MSI_MESSAGE_DATA_64);
> + reg = ep->msi_cap + PCI_MSI_ADDRESS_HI;
> + msg_addr_upper = dw_pcie_readl_dbi(pci, reg);
> + reg = ep->msi_cap + PCI_MSI_DATA_64;
> + msg_data = dw_pcie_readw_dbi(pci, reg);
> } else {
> msg_addr_upper = 0;
> - msg_data = dw_pcie_readw_dbi(pci, MSI_MESSAGE_DATA_32);
> + reg = ep->msi_cap + PCI_MSI_DATA_32;
> + msg_data = dw_pcie_readw_dbi(pci, reg);
> }
> msg_addr = ((u64) msg_addr_upper) << 32 | msg_addr_lower;
> ret = dw_pcie_ep_map_addr(epc, func_no, ep->msi_mem_phys, msg_addr,
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index b22c5bb..a0ab12f 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -96,17 +96,6 @@
> #define PCIE_GET_ATU_INB_UNR_REG_OFFSET(region) \
> ((0x3 << 20) | ((region) << 9) | (0x1 << 8))
>
> -#define MSI_MESSAGE_CONTROL 0x52
> -#define MSI_CAP_MMC_SHIFT 1
> -#define MSI_CAP_MMC_MASK (7 << MSI_CAP_MMC_SHIFT)
> -#define MSI_CAP_MME_SHIFT 4
> -#define MSI_CAP_MSI_EN_MASK 0x1
> -#define MSI_CAP_MME_MASK (7 << MSI_CAP_MME_SHIFT)
> -#define MSI_MESSAGE_ADDR_L32 0x54
> -#define MSI_MESSAGE_ADDR_U32 0x58
> -#define MSI_MESSAGE_DATA_32 0x58
> -#define MSI_MESSAGE_DATA_64 0x5C
> -
> #define MAX_MSI_IRQS 256
> #define MAX_MSI_IRQS_PER_CTRL 32
> #define MAX_MSI_CTRLS (MAX_MSI_IRQS / MAX_MSI_IRQS_PER_CTRL)
> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> index c72e656..094dcc3 100644
> --- a/drivers/pci/endpoint/pci-epc-core.c
> +++ b/drivers/pci/endpoint/pci-epc-core.c
> @@ -201,7 +201,8 @@ int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 interrupts)
> u8 encode_int;
> unsigned long flags;
>
> - if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
> + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions ||
> + interrupts > 32)
> return -EINVAL;

This is not related to $patch->subject

Thanks
Kishon