Subject: Re: [PATCH 01/10] PCI: designware-ep: Add multiple PFs support for DWC

From: Andrew Murray <[email-masked]>
Date: Fri, 16 Aug 2019 10:44:50 +0100

On Fri, Aug 16, 2019 at 02:55:41AM +0000, Xiaowei Bao wrote:
> 
> 
> > -----Original Message-----
> > From: Andrew Murray <[email-masked]>
> > Sent: 2019年8月15日 19:32
> > To: Xiaowei Bao <[email-masked]>
> > Cc: [email-masked]; [email-masked];
> > [email-masked]; [email-masked]; [email-masked];
> > [email-masked]; Leo Li <[email-masked]>; [email-masked];
> > [email-masked]; [email-masked]; [email-masked];
> > M.h. Lian <[email-masked]>; Mingkai Hu <[email-masked]>;
> > Roy Zang <[email-masked]>; [email-masked];
> > [email-masked]; [email-masked];
> > [email-masked]; [email-masked]
> > Subject: Re: [PATCH 01/10] PCI: designware-ep: Add multiple PFs support for
> > DWC
> > 
> > On Thu, Aug 15, 2019 at 04:37:07PM +0800, Xiaowei Bao wrote:
> > > Add multiple PFs support for DWC, different PF have different config
> > > space, we use pf-offset property which get from the DTS to access the
> > > different pF config space.
> > 
> > Thanks for the patch. I haven't seen a cover letter for this series, is there one
> > missing?
> Maybe I miss, I will add you to review next time, thanks a lot for your comments.
> > 
> > 
> > >
> > > Signed-off-by: Xiaowei Bao <[email-masked]>
> > > ---
> > >  drivers/pci/controller/dwc/pcie-designware-ep.c |  97
> > +++++++++++++---------
> > >  drivers/pci/controller/dwc/pcie-designware.c    | 105
> > ++++++++++++++++++++++--
> > >  drivers/pci/controller/dwc/pcie-designware.h    |  10 ++-
> > >  include/linux/pci-epc.h                         |   1 +
> > >  4 files changed, 164 insertions(+), 49 deletions(-)
> > >
> > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > index 2bf5a35..75e2955 100644
> > > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > @@ -19,12 +19,14 @@ void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
> > >  	pci_epc_linkup(epc);
> > >  }
> > >
> > > -static void __dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno
> > bar,
> > > -				   int flags)
> > > +static void __dw_pcie_ep_reset_bar(struct dw_pcie *pci, u8 func_no,
> > > +				   enum pci_barno bar, int flags)
> > >  {
> > >  	u32 reg;
> > > +	struct pci_epc *epc = pci->ep.epc;
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >
> > > -	reg = PCI_BASE_ADDRESS_0 + (4 * bar);
> > > +	reg = pf_base + PCI_BASE_ADDRESS_0 + (4 * bar);
> > 
> > I think I'd rather see this arithmetic (and the one for determining pf_base)
> > inside a macro or inline header function. This would make this code more
> > readable and reduce the chances of an error by avoiding duplication of code.
> > 
> > For example look at cdns_pcie_ep_fn_writeb and
> > ROCKCHIP_PCIE_EP_FUNC_BASE for examples of other EP drivers that do
> > this.
> Agree, this looks fine, thanks a lot for your comments, I will use this way to access
> the registers in next version patch.
> > 
> > 
> > >  	dw_pcie_dbi_ro_wr_en(pci);
> > >  	dw_pcie_writel_dbi2(pci, reg, 0x0);
> > >  	dw_pcie_writel_dbi(pci, reg, 0x0);
> > > @@ -37,7 +39,12 @@ static void __dw_pcie_ep_reset_bar(struct dw_pcie
> > > *pci, enum pci_barno bar,
> > >
> > >  void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)  {
> > > -	__dw_pcie_ep_reset_bar(pci, bar, 0);
> > > +	u8 func_no, funcs;
> > > +
> > > +	funcs = pci->ep.epc->max_functions;
> > > +
> > > +	for (func_no = 0; func_no < funcs; func_no++)
> > > +		__dw_pcie_ep_reset_bar(pci, func_no, bar, 0);
> > >  }
> > >
> > >  static u8 __dw_pcie_ep_find_next_cap(struct dw_pcie *pci, u8 cap_ptr,
> > > @@ -78,28 +85,29 @@ static int dw_pcie_ep_write_header(struct pci_epc
> > > *epc, u8 func_no,  {
> > >  	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >
> > >  	dw_pcie_dbi_ro_wr_en(pci);
> > > -	dw_pcie_writew_dbi(pci, PCI_VENDOR_ID, hdr->vendorid);
> > > -	dw_pcie_writew_dbi(pci, PCI_DEVICE_ID, hdr->deviceid);
> > > -	dw_pcie_writeb_dbi(pci, PCI_REVISION_ID, hdr->revid);
> > > -	dw_pcie_writeb_dbi(pci, PCI_CLASS_PROG, hdr->progif_code);
> > > -	dw_pcie_writew_dbi(pci, PCI_CLASS_DEVICE,
> > > +	dw_pcie_writew_dbi(pci, pf_base + PCI_VENDOR_ID, hdr->vendorid);
> > > +	dw_pcie_writew_dbi(pci, pf_base + PCI_DEVICE_ID, hdr->deviceid);
> > > +	dw_pcie_writeb_dbi(pci, pf_base + PCI_REVISION_ID, hdr->revid);
> > > +	dw_pcie_writeb_dbi(pci, pf_base + PCI_CLASS_PROG, hdr->progif_code);
> > > +	dw_pcie_writew_dbi(pci, pf_base + PCI_CLASS_DEVICE,
> > >  			   hdr->subclass_code | hdr->baseclass_code << 8);
> > > -	dw_pcie_writeb_dbi(pci, PCI_CACHE_LINE_SIZE,
> > > +	dw_pcie_writeb_dbi(pci, pf_base + PCI_CACHE_LINE_SIZE,
> > >  			   hdr->cache_line_size);
> > > -	dw_pcie_writew_dbi(pci, PCI_SUBSYSTEM_VENDOR_ID,
> > > +	dw_pcie_writew_dbi(pci, pf_base + PCI_SUBSYSTEM_VENDOR_ID,
> > >  			   hdr->subsys_vendor_id);
> > > -	dw_pcie_writew_dbi(pci, PCI_SUBSYSTEM_ID, hdr->subsys_id);
> > > -	dw_pcie_writeb_dbi(pci, PCI_INTERRUPT_PIN,
> > > +	dw_pcie_writew_dbi(pci, pf_base + PCI_SUBSYSTEM_ID,
> > hdr->subsys_id);
> > > +	dw_pcie_writeb_dbi(pci, pf_base + PCI_INTERRUPT_PIN,
> > >  			   hdr->interrupt_pin);
> > >  	dw_pcie_dbi_ro_wr_dis(pci);
> > >
> > >  	return 0;
> > >  }
> > >
> > > -static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, enum
> > pci_barno bar,
> > > -				  dma_addr_t cpu_addr,
> > > +static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no,
> > > +				  enum pci_barno bar, dma_addr_t cpu_addr,
> > >  				  enum dw_pcie_as_type as_type)
> > >  {
> > >  	int ret;
> > > @@ -112,7 +120,7 @@ static int dw_pcie_ep_inbound_atu(struct
> > dw_pcie_ep *ep, enum pci_barno bar,
> > >  		return -EINVAL;
> > >  	}
> > >
> > > -	ret = dw_pcie_prog_inbound_atu(pci, free_win, bar, cpu_addr,
> > > +	ret = dw_pcie_prog_inbound_atu(pci, func_no, free_win, bar,
> > > +cpu_addr,
> > >  				       as_type);
> > >  	if (ret < 0) {
> > >  		dev_err(pci->dev, "Failed to program IB window\n"); @@ -125,7
> > > +133,8 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep,
> > enum pci_barno bar,
> > >  	return 0;
> > >  }
> > >
> > > -static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, phys_addr_t
> > > phys_addr,
> > > +static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, u8 func_no,
> > > +				   phys_addr_t phys_addr,
> > >  				   u64 pci_addr, size_t size)
> > >  {
> > >  	u32 free_win;
> > > @@ -137,8 +146,8 @@ static int dw_pcie_ep_outbound_atu(struct
> > dw_pcie_ep *ep, phys_addr_t phys_addr,
> > >  		return -EINVAL;
> > >  	}
> > >
> > > -	dw_pcie_prog_outbound_atu(pci, free_win, PCIE_ATU_TYPE_MEM,
> > > -				  phys_addr, pci_addr, size);
> > > +	dw_pcie_prog_ep_outbound_atu(pci, func_no, free_win,
> > PCIE_ATU_TYPE_MEM,
> > > +				     phys_addr, pci_addr, size);
> > >
> > >  	set_bit(free_win, ep->ob_window_map);
> > >  	ep->outbound_addr[free_win] = phys_addr; @@ -154,7 +163,7 @@
> > static
> > > void dw_pcie_ep_clear_bar(struct pci_epc *epc, u8 func_no,
> > >  	enum pci_barno bar = epf_bar->barno;
> > >  	u32 atu_index = ep->bar_to_atu[bar];
> > >
> > > -	__dw_pcie_ep_reset_bar(pci, bar, epf_bar->flags);
> > > +	__dw_pcie_ep_reset_bar(pci, func_no, bar, epf_bar->flags);
> > >
> > >  	dw_pcie_disable_atu(pci, atu_index, DW_PCIE_REGION_INBOUND);
> > >  	clear_bit(atu_index, ep->ib_window_map); @@ -170,14 +179,16 @@
> > > static int dw_pcie_ep_set_bar(struct pci_epc *epc, u8 func_no,
> > >  	size_t size = epf_bar->size;
> > >  	int flags = epf_bar->flags;
> > >  	enum dw_pcie_as_type as_type;
> > > -	u32 reg = PCI_BASE_ADDRESS_0 + (4 * bar);
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > > +	u32 reg = PCI_BASE_ADDRESS_0 + (4 * bar) + pf_base;
> > >
> > >  	if (!(flags & PCI_BASE_ADDRESS_SPACE))
> > >  		as_type = DW_PCIE_AS_MEM;
> > >  	else
> > >  		as_type = DW_PCIE_AS_IO;
> > >
> > > -	ret = dw_pcie_ep_inbound_atu(ep, bar, epf_bar->phys_addr, as_type);
> > > +	ret = dw_pcie_ep_inbound_atu(ep, func_no, bar,
> > > +				     epf_bar->phys_addr, as_type);
> > >  	if (ret)
> > >  		return ret;
> > >
> > > @@ -235,7 +246,7 @@ static int dw_pcie_ep_map_addr(struct pci_epc
> > *epc, u8 func_no,
> > >  	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > >
> > > -	ret = dw_pcie_ep_outbound_atu(ep, addr, pci_addr, size);
> > > +	ret = dw_pcie_ep_outbound_atu(ep, func_no, addr, pci_addr, size);
> > >  	if (ret) {
> > >  		dev_err(pci->dev, "Failed to enable address\n");
> > >  		return ret;
> > > @@ -248,12 +259,13 @@ static int dw_pcie_ep_get_msi(struct pci_epc
> > > *epc, u8 func_no)  {
> > >  	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >  	u32 val, reg;
> > >
> > >  	if (!ep->msi_cap)
> > >  		return -EINVAL;
> > >
> > > -	reg = ep->msi_cap + PCI_MSI_FLAGS;
> > > +	reg = ep->msi_cap + pf_base + PCI_MSI_FLAGS;
> > >  	val = dw_pcie_readw_dbi(pci, reg);
> > >  	if (!(val & PCI_MSI_FLAGS_ENABLE))
> > >  		return -EINVAL;
> > > @@ -267,12 +279,13 @@ static int dw_pcie_ep_set_msi(struct pci_epc
> > > *epc, u8 func_no, u8 interrupts)  {
> > >  	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >  	u32 val, reg;
> > >
> > >  	if (!ep->msi_cap)
> > >  		return -EINVAL;
> > >
> > > -	reg = ep->msi_cap + PCI_MSI_FLAGS;
> > > +	reg = ep->msi_cap + pf_base + PCI_MSI_FLAGS;
> > >  	val = dw_pcie_readw_dbi(pci, reg);
> > >  	val &= ~PCI_MSI_FLAGS_QMASK;
> > >  	val |= (interrupts << 1) & PCI_MSI_FLAGS_QMASK; @@ -287,12 +300,13
> > > @@ static int dw_pcie_ep_get_msix(struct pci_epc *epc, u8 func_no)  {
> > >  	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >  	u32 val, reg;
> > >
> > >  	if (!ep->msix_cap)
> > >  		return -EINVAL;
> > >
> > > -	reg = ep->msix_cap + PCI_MSIX_FLAGS;
> > > +	reg = ep->msix_cap + pf_base + PCI_MSIX_FLAGS;
> > >  	val = dw_pcie_readw_dbi(pci, reg);
> > >  	if (!(val & PCI_MSIX_FLAGS_ENABLE))
> > >  		return -EINVAL;
> > > @@ -306,12 +320,13 @@ static int dw_pcie_ep_set_msix(struct pci_epc
> > > *epc, u8 func_no, u16 interrupts)  {
> > >  	struct dw_pcie_ep *ep = epc_get_drvdata(epc);
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >  	u32 val, reg;
> > >
> > >  	if (!ep->msix_cap)
> > >  		return -EINVAL;
> > >
> > > -	reg = ep->msix_cap + PCI_MSIX_FLAGS;
> > > +	reg = ep->msix_cap + pf_base + PCI_MSIX_FLAGS;
> > >  	val = dw_pcie_readw_dbi(pci, reg);
> > >  	val &= ~PCI_MSIX_FLAGS_QSIZE;
> > >  	val |= interrupts;
> > > @@ -400,6 +415,7 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep
> > *ep, u8 func_no,
> > >  	unsigned int aligned_offset;
> > >  	u16 msg_ctrl, msg_data;
> > >  	u32 msg_addr_lower, msg_addr_upper, reg;
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >  	u64 msg_addr;
> > >  	bool has_upper;
> > >  	int ret;
> > > @@ -408,19 +424,19 @@ int dw_pcie_ep_raise_msi_irq(struct
> > dw_pcie_ep *ep, u8 func_no,
> > >  		return -EINVAL;
> > >
> > >  	/* Raise MSI per the PCI Local Bus Specification Revision 3.0, 6.8.1. */
> > > -	reg = ep->msi_cap + PCI_MSI_FLAGS;
> > > +	reg = ep->msi_cap + pf_base + PCI_MSI_FLAGS;
> > >  	msg_ctrl = dw_pcie_readw_dbi(pci, reg);
> > >  	has_upper = !!(msg_ctrl & PCI_MSI_FLAGS_64BIT);
> > > -	reg = ep->msi_cap + PCI_MSI_ADDRESS_LO;
> > > +	reg = ep->msi_cap + pf_base + PCI_MSI_ADDRESS_LO;
> > >  	msg_addr_lower = dw_pcie_readl_dbi(pci, reg);
> > >  	if (has_upper) {
> > > -		reg = ep->msi_cap + PCI_MSI_ADDRESS_HI;
> > > +		reg = ep->msi_cap + pf_base + PCI_MSI_ADDRESS_HI;
> > >  		msg_addr_upper = dw_pcie_readl_dbi(pci, reg);
> > > -		reg = ep->msi_cap + PCI_MSI_DATA_64;
> > > +		reg = ep->msi_cap + pf_base + PCI_MSI_DATA_64;
> > >  		msg_data = dw_pcie_readw_dbi(pci, reg);
> > >  	} else {
> > >  		msg_addr_upper = 0;
> > > -		reg = ep->msi_cap + PCI_MSI_DATA_32;
> > > +		reg = ep->msi_cap + pf_base + PCI_MSI_DATA_32;
> > >  		msg_data = dw_pcie_readw_dbi(pci, reg);
> > >  	}
> > >  	aligned_offset = msg_addr_lower & (epc->mem->page_size - 1); @@
> > > -439,7 +455,7 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep,
> > > u8 func_no,  }
> > >
> > >  int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
> > > -			     u16 interrupt_num)
> > > +			      u16 interrupt_num)
> > >  {
> > >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > >  	struct pci_epc *epc = ep->epc;
> > > @@ -447,16 +463,17 @@ int dw_pcie_ep_raise_msix_irq(struct
> > dw_pcie_ep *ep, u8 func_no,
> > >  	u32 bar_addr_upper, bar_addr_lower;
> > >  	u32 msg_addr_upper, msg_addr_lower;
> > >  	u32 reg, msg_data, vec_ctrl;
> > > +	u32 pf_base = func_no * epc->pf_offset;
> > >  	u64 tbl_addr, msg_addr, reg_u64;
> > >  	void __iomem *msix_tbl;
> > >  	int ret;
> > >
> > > -	reg = ep->msix_cap + PCI_MSIX_TABLE;
> > > +	reg = ep->msix_cap + pf_base + PCI_MSIX_TABLE;
> > >  	tbl_offset = dw_pcie_readl_dbi(pci, reg);
> > >  	bir = (tbl_offset & PCI_MSIX_TABLE_BIR);
> > >  	tbl_offset &= PCI_MSIX_TABLE_OFFSET;
> > >
> > > -	reg = PCI_BASE_ADDRESS_0 + (4 * bir);
> > > +	reg = PCI_BASE_ADDRESS_0 + pf_base + (4 * bir);
> > >  	bar_addr_upper = 0;
> > >  	bar_addr_lower = dw_pcie_readl_dbi(pci, reg);
> > >  	reg_u64 = (bar_addr_lower & PCI_BASE_ADDRESS_MEM_TYPE_MASK);
> > @@
> > > -592,13 +609,17 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> > >  	ep->epc = epc;
> > >  	epc_set_drvdata(epc, ep);
> > >
> > > -	if (ep->ops->ep_init)
> > > -		ep->ops->ep_init(ep);
> > > -
> > >  	ret = of_property_read_u8(np, "max-functions", &epc->max_functions);
> > >  	if (ret < 0)
> > >  		epc->max_functions = 1;
> > >
> > > +	ret = of_property_read_u32(np, "pf-offset", &epc->pf_offset);
> > > +	if (ret < 0)
> > > +		epc->pf_offset = 0;
> > 
> > Bad things will likely happen if max_functions > 1 and pf-offset isn't set.
> > I think the driver should bail in this situation. It would be very easy for
> > someone to misconfigure this.
> Yes, you are right, but if the max-functions have defined in DTS, require the pf-offset
> must define in DTS, I am not sure the correct value of pf-offsetfor other platforms, 
> so I think the max-functions and pf-offset should not have the dependence.

Yes you're correct. I hadn't really thought about this beyond layerscape. It's
also possible that other hardware could support multiple PFs without relying on
an offset and perhaps employ some other mechanism to access different
functions. So whilst this property can be optional for the majority of dwc
controllers - it must be set and cannot be zero for layerscape.

Perhaps inside ls_pcie_ep_init, you can set max_functions to 1 if pf_offset is
0 and print a WARN to explain why? (Or ls_pcie_ep_init returns failure and
dw_pcie_ep_init checks it and bails).

The assumption is being made here that future dw controllers may also use
pf_offset (is this likely?) - otherwise why is this in pcie-designware-ep.c and
not pci-layerscape-ep.c and why is this value not just hard-coded for lp?

> even though I didn't define pf-offset when I defined max-functions, the pf-offset is 0, 
> the DWC ep driver can continue run the progress of INIT but not return, of course, 
> thus the PF1 will not work, I don't know which way is better.
> > 
> > 
> > > +
> > > +	if (ep->ops->ep_init)
> > > +		ep->ops->ep_init(ep);
> > > +
> > >  	ret = __pci_epc_mem_init(epc, ep->phys_base, ep->addr_size,
> > >  				 ep->page_size);
> > >  	if (ret < 0) {
> > > diff --git a/drivers/pci/controller/dwc/pcie-designware.c
> > > b/drivers/pci/controller/dwc/pcie-designware.c
> > > index 7d25102..c99cee4 100644
> > > --- a/drivers/pci/controller/dwc/pcie-designware.c
> > > +++ b/drivers/pci/controller/dwc/pcie-designware.c
> > > @@ -158,6 +158,43 @@ static void dw_pcie_writel_ob_unroll(struct
> > dw_pcie *pci, u32 index, u32 reg,
> > >  	dw_pcie_writel_atu(pci, offset + reg, val);  }
> > >
> > > +static void dw_pcie_prog_ep_outbound_atu_unroll(struct dw_pcie *pci, u8
> > func_no,
> > > +						int index, int type,
> > > +						u64 cpu_addr, u64 pci_addr,
> > > +						u32 size)
> > > +{
> > > +	u32 retries, val;
> > > +
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_LOWER_BASE,
> > > +				 lower_32_bits(cpu_addr));
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_BASE,
> > > +				 upper_32_bits(cpu_addr));
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_LIMIT,
> > > +				 lower_32_bits(cpu_addr + size - 1));
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_LOWER_TARGET,
> > > +				 lower_32_bits(pci_addr));
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
> > > +				 upper_32_bits(pci_addr));
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1,
> > > +				 type | PCIE_ATU_FUNC_NUM(func_no));
> > 
> > With the exception of this line, the rest of this function is identical to
> > dw_pcie_prog_outbound_atu_unroll.
> Yes, I can integrate the same code, but I think we'd better use the different outbound 
> window set function between RC and EP, because the RC don't need the func_num parameter.

> > 
> > > +	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL2,
> > > +				 PCIE_ATU_ENABLE);
> > > +
> > > +	/*
> > > +	 * Make sure ATU enable takes effect before any subsequent config
> > > +	 * and I/O accesses.
> > > +	 */
> > > +	for (retries = 0; retries < LINK_WAIT_MAX_IATU_RETRIES; retries++) {
> > > +		val = dw_pcie_readl_ob_unroll(pci, index,
> > > +					      PCIE_ATU_UNR_REGION_CTRL2);
> > > +		if (val & PCIE_ATU_ENABLE)
> > > +			return;
> > > +
> > > +		mdelay(LINK_WAIT_IATU);
> > > +	}
> > > +	dev_err(pci->dev, "Outbound iATU is not being enabled\n"); }
> > > +
> > >  static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, int
> > index,
> > >  					     int type, u64 cpu_addr,
> > >  					     u64 pci_addr, u32 size)
> > > @@ -194,6 +231,51 @@ static void
> > dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, int index,
> > >  	dev_err(pci->dev, "Outbound iATU is not being enabled\n");  }
> > >
> > > +void dw_pcie_prog_ep_outbound_atu(struct dw_pcie *pci, u8 func_no, int
> > index,
> > > +				  int type, u64 cpu_addr, u64 pci_addr,
> > > +				  u32 size)
> > > +{
> > > +	u32 retries, val;
> > > +
> > > +	if (pci->ops->cpu_addr_fixup)
> > > +		cpu_addr = pci->ops->cpu_addr_fixup(pci, cpu_addr);
> > > +
> > > +	if (pci->iatu_unroll_enabled) {
> > > +		dw_pcie_prog_ep_outbound_atu_unroll(pci, func_no, index, type,
> > > +						    cpu_addr, pci_addr, size);
> > > +		return;
> > > +	}
> > > +
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_VIEWPORT,
> > > +			   PCIE_ATU_REGION_OUTBOUND | index);
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_LOWER_BASE,
> > > +			   lower_32_bits(cpu_addr));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_BASE,
> > > +			   upper_32_bits(cpu_addr));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_LIMIT,
> > > +			   lower_32_bits(cpu_addr + size - 1));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_LOWER_TARGET,
> > > +			   lower_32_bits(pci_addr));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_TARGET,
> > > +			   upper_32_bits(pci_addr));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
> > > +			   PCIE_ATU_FUNC_NUM(func_no));
> > 
> > The same here, this is identical to dw_pcie_prog_outbound_atu with the
> > exception of this line.
> > 
> > Is there a way you can avoid all of this duplicated code?
> As above, I can integrate the same code, but I keep to think the different outbound 
> Window set function should be used between RC and EP.

Or, is it possible to keep and use the existing functions, but use them
differently, e.g:

@@ -137,8 +146,8 @@ static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, phys_addr_t phys_addr,
                return -EINVAL;
        }

-       dw_pcie_prog_outbound_atu(pci, free_win, PCIE_ATU_TYPE_MEM,
-                                 phys_addr, pci_addr, size);
+       dw_pcie_prog_outbound_atu(pci, free_win, PCIE_ATU_TYPE_MEM_FUNC(func_no),
+                                    phys_addr, pci_addr, size);

        set_bit(free_win, ep->ob_window_map);
        ep->outbound_addr[free_win] = phys_addr;

Supported with:

#define PCIE_ATU_TYPE_MEM               0x0
#define PCIE_ATU_TYPE_MEM_FUNC(func_no) (PCIE_ATU_TYPE_MEM | PCIE_ATU_FUNC_NUM(func_no))

This is just a suggestion, but I'm keen to avoid code duplication.

> > 
> > Thanks,
> > 
> > Andrew Murray
> > 
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE);
> > > +
> > > +	/*
> > > +	 * Make sure ATU enable takes effect before any subsequent config
> > > +	 * and I/O accesses.
> > > +	 */
> > > +	for (retries = 0; retries < LINK_WAIT_MAX_IATU_RETRIES; retries++) {
> > > +		val = dw_pcie_readl_dbi(pci, PCIE_ATU_CR2);
> > > +		if (val & PCIE_ATU_ENABLE)
> > > +			return;
> > > +
> > > +		mdelay(LINK_WAIT_IATU);
> > > +	}
> > > +	dev_err(pci->dev, "Outbound iATU is not being enabled\n"); }
> > > +
> > >  void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
> > >  			       u64 cpu_addr, u64 pci_addr, u32 size)  { @@ -252,8
> > +334,8
> > > @@ static void dw_pcie_writel_ib_unroll(struct dw_pcie *pci, u32 index,
> > u32 reg,
> > >  	dw_pcie_writel_atu(pci, offset + reg, val);  }
> > >
> > > -static int dw_pcie_prog_inbound_atu_unroll(struct dw_pcie *pci, int index,
> > > -					   int bar, u64 cpu_addr,
> > > +static int dw_pcie_prog_inbound_atu_unroll(struct dw_pcie *pci, u8
> > func_no,
> > > +					   int index, int bar, u64 cpu_addr,
> > >  					   enum dw_pcie_as_type as_type)  {
> > >  	int type;
> > > @@ -275,8 +357,10 @@ static int dw_pcie_prog_inbound_atu_unroll(struct
> > dw_pcie *pci, int index,
> > >  		return -EINVAL;
> > >  	}
> > >
> > > -	dw_pcie_writel_ib_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1,
> > type);
> > > +	dw_pcie_writel_ib_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1,
> > type |
> > > +				 PCIE_ATU_FUNC_NUM(func_no));
> > >  	dw_pcie_writel_ib_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL2,
> > > +				 PCIE_ATU_FUNC_NUM_MATCH_EN |
> > >  				 PCIE_ATU_ENABLE |
> > >  				 PCIE_ATU_BAR_MODE_ENABLE | (bar << 8));
> > >
> > > @@ -297,14 +381,15 @@ static int
> > dw_pcie_prog_inbound_atu_unroll(struct dw_pcie *pci, int index,
> > >  	return -EBUSY;
> > >  }
> > >
> > > -int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int bar,
> > > -			     u64 cpu_addr, enum dw_pcie_as_type as_type)
> > > +int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, u8 func_no, int index,
> > > +			     int bar, u64 cpu_addr,
> > > +			     enum dw_pcie_as_type as_type)
> > >  {
> > >  	int type;
> > >  	u32 retries, val;
> > >
> > >  	if (pci->iatu_unroll_enabled)
> > > -		return dw_pcie_prog_inbound_atu_unroll(pci, index, bar,
> > > +		return dw_pcie_prog_inbound_atu_unroll(pci, func_no, index, bar,
> > >  						       cpu_addr, as_type);
> > >
> > >  	dw_pcie_writel_dbi(pci, PCIE_ATU_VIEWPORT,
> > PCIE_ATU_REGION_INBOUND |
> > > @@ -323,9 +408,11 @@ int dw_pcie_prog_inbound_atu(struct dw_pcie
> > *pci, int index, int bar,
> > >  		return -EINVAL;
> > >  	}
> > >
> > > -	dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type);
> > > -	dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE
> > > -			   | PCIE_ATU_BAR_MODE_ENABLE | (bar << 8));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
> > > +			   PCIE_ATU_FUNC_NUM(func_no));
> > > +	dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE |
> > > +			   PCIE_ATU_FUNC_NUM_MATCH_EN |
> > > +			   PCIE_ATU_BAR_MODE_ENABLE | (bar << 8));
> > >
> > >  	/*
> > >  	 * Make sure ATU enable takes effect before any subsequent config
> > > diff --git a/drivers/pci/controller/dwc/pcie-designware.h
> > > b/drivers/pci/controller/dwc/pcie-designware.h
> > > index ffed084..2b291e8 100644
> > > --- a/drivers/pci/controller/dwc/pcie-designware.h
> > > +++ b/drivers/pci/controller/dwc/pcie-designware.h
> > > @@ -71,9 +71,11 @@
> > >  #define PCIE_ATU_TYPE_IO		0x2
> > >  #define PCIE_ATU_TYPE_CFG0		0x4
> > >  #define PCIE_ATU_TYPE_CFG1		0x5
> > > +#define PCIE_ATU_FUNC_NUM(pf)           (pf << 20)
> > >  #define PCIE_ATU_CR2			0x908
> > >  #define PCIE_ATU_ENABLE			BIT(31)
> > >  #define PCIE_ATU_BAR_MODE_ENABLE	BIT(30)
> > > +#define PCIE_ATU_FUNC_NUM_MATCH_EN      BIT(19)
> > >  #define PCIE_ATU_LOWER_BASE		0x90C
> > >  #define PCIE_ATU_UPPER_BASE		0x910
> > >  #define PCIE_ATU_LIMIT			0x914
> > > @@ -265,8 +267,12 @@ int dw_pcie_wait_for_link(struct dw_pcie *pci);
> > > void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index,
> > >  			       int type, u64 cpu_addr, u64 pci_addr,
> > >  			       u32 size);
> > > -int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int bar,
> > > -			     u64 cpu_addr, enum dw_pcie_as_type as_type);
> > > +void dw_pcie_prog_ep_outbound_atu(struct dw_pcie *pci, u8 func_no, int
> > index,
> > > +				  int type, u64 cpu_addr, u64 pci_addr,
> > > +				  u32 size);
> > > +int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, u8 func_no, int index,
> > > +			     int bar, u64 cpu_addr,
> > > +			     enum dw_pcie_as_type as_type);
> > >  void dw_pcie_disable_atu(struct dw_pcie *pci, int index,
> > >  			 enum dw_pcie_region_type type);
> > >  void dw_pcie_setup(struct dw_pcie *pci); diff --git
> > > a/include/linux/pci-epc.h b/include/linux/pci-epc.h index
> > > f641bad..fc2feee 100644
> > > --- a/include/linux/pci-epc.h
> > > +++ b/include/linux/pci-epc.h
> > > @@ -96,6 +96,7 @@ struct pci_epc {
> > >  	const struct pci_epc_ops	*ops;
> > >  	struct pci_epc_mem		*mem;
> > >  	u8				max_functions;
> > > +	u32				pf_offset;

Also pf_offset is an implementation detail needed only by the driver to
calculate where the PF is - it doesn't seem right that we share this with the
EP controller framework (whereas max_functions is used as a bounds check
for func_no in the framework calls).

I'd suggest that pf_offset is moved to a dwc structure, perhaps dw_pcie_ep?

Thanks,

Andrew Murray

> > >  	struct config_group		*group;
> > >  	/* spinlock to protect against concurrent access of EP controller */
> > >  	spinlock_t			lock;
> > > --
> > > 2.9.5
> > >
> > >
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