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

[Kishon Vijay Abraham I <kishon@ti.com>]

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@synopsys.com>
> ---
> 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