Re: [PATCH v2 08/10] PCI: layerscape: Add EP mode support for ls1088a and ls2088a

From: christophe leroy
Date: Sat Aug 24 2019 - 02:46:02 EST




Le 24/08/2019 Ã 02:18, Xiaowei Bao a ÃcritÂ:


-----Original Message-----
From: Andrew Murray <andrew.murray@xxxxxxx>
Sent: 2019å8æ23æ 22:28
To: Xiaowei Bao <xiaowei.bao@xxxxxxx>
Cc: bhelgaas@xxxxxxxxxx; robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx;
shawnguo@xxxxxxxxxx; Leo Li <leoyang.li@xxxxxxx>; kishon@xxxxxx;
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Lian <minghuan.lian@xxxxxxx>; Mingkai Hu <mingkai.hu@xxxxxxx>; Roy
Zang <roy.zang@xxxxxxx>; jingoohan1@xxxxxxxxx;
gustavo.pimentel@xxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx;
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Subject: Re: [PATCH v2 08/10] PCI: layerscape: Add EP mode support for
ls1088a and ls2088a

On Thu, Aug 22, 2019 at 07:22:40PM +0800, Xiaowei Bao wrote:
Add PCIe EP mode support for ls1088a and ls2088a, there are some
difference between LS1 and LS2 platform, so refactor the code of the
EP driver.

Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx>
---
v2:
- New mechanism for layerscape EP driver.

Was there a v1 of this patch?

Yes, but I don't know how to comments, ^_^

As far as I can see, in the previous version of the series (https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=125315&state=*), the 8/10 was something completely different, and I can't find any other patch in the series that could have been the v1 of this patch.

Christophe




drivers/pci/controller/dwc/pci-layerscape-ep.c | 76
++++++++++++++++++++------
1 file changed, 58 insertions(+), 18 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c
b/drivers/pci/controller/dwc/pci-layerscape-ep.c
index 7ca5fe8..2a66f07 100644
--- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
+++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
@@ -20,27 +20,29 @@

#define PCIE_DBI2_OFFSET 0x1000 /* DBI2 base address*/

-struct ls_pcie_ep {
- struct dw_pcie *pci;
- struct pci_epc_features *ls_epc;
+#define to_ls_pcie_ep(x) dev_get_drvdata((x)->dev)
+
+struct ls_pcie_ep_drvdata {
+ u32 func_offset;
+ const struct dw_pcie_ep_ops *ops;
+ const struct dw_pcie_ops *dw_pcie_ops;
};

-#define to_ls_pcie_ep(x) dev_get_drvdata((x)->dev)
+struct ls_pcie_ep {
+ struct dw_pcie *pci;
+ struct pci_epc_features *ls_epc;
+ const struct ls_pcie_ep_drvdata *drvdata; };

static int ls_pcie_establish_link(struct dw_pcie *pci) {
return 0;
}

-static const struct dw_pcie_ops ls_pcie_ep_ops = {
+static const struct dw_pcie_ops dw_ls_pcie_ep_ops = {
.start_link = ls_pcie_establish_link, };

-static const struct of_device_id ls_pcie_ep_of_match[] = {
- { .compatible = "fsl,ls-pcie-ep",},
- { },
-};
-
static const struct pci_epc_features* ls_pcie_ep_get_features(struct
dw_pcie_ep *ep) { @@ -82,10 +84,44 @@ static int
ls_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
}
}

-static const struct dw_pcie_ep_ops pcie_ep_ops = {
+static unsigned int ls_pcie_ep_func_conf_select(struct dw_pcie_ep *ep,
+ u8 func_no)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ struct ls_pcie_ep *pcie = to_ls_pcie_ep(pci);
+ u8 header_type;
+
+ header_type = ioread8(pci->dbi_base + PCI_HEADER_TYPE);
+
+ if (header_type & (1 << 7))
+ return pcie->drvdata->func_offset * func_no;
+ else
+ return 0;

It looks like there isn't a PCI define for multi function, the nearest I could find
was PCI_HEADER_TYPE_MULTIDEVICE in hotplug/ibmphp.h. A comment
above the test might be helpful to explain the test.

Yes, I have not find the PCI_HEADER_TYPE_MULTIDEVICE define. OK, I will add
The comments in next version patch.


As the ls_pcie_ep_drvdata structures are static, the unset .func_offset will be
initialised to 0, so you could just drop the test above.

OK, thanks


However something to the effect of the following may help spot
misconfiguration:

WARN_ON(func_no && !pcie->drvdata->func_offset); return
pcie->drvdata->func_offset * func_no;

Thanks a lot, this looks better.


The WARN is probably quite useful as if you are attempting to use non-zero
functions and func_offset isn't set - then things may appear to work normally
but actually will break horribly.

got it, thanks.


Thanks,

Andrew Murray

+}
+
+static const struct dw_pcie_ep_ops ls_pcie_ep_ops = {
.ep_init = ls_pcie_ep_init,
.raise_irq = ls_pcie_ep_raise_irq,
.get_features = ls_pcie_ep_get_features,
+ .func_conf_select = ls_pcie_ep_func_conf_select, };
+
+static const struct ls_pcie_ep_drvdata ls1_ep_drvdata = {
+ .ops = &ls_pcie_ep_ops,
+ .dw_pcie_ops = &dw_ls_pcie_ep_ops,
+};
+
+static const struct ls_pcie_ep_drvdata ls2_ep_drvdata = {
+ .func_offset = 0x20000,
+ .ops = &ls_pcie_ep_ops,
+ .dw_pcie_ops = &dw_ls_pcie_ep_ops,
+};
+
+static const struct of_device_id ls_pcie_ep_of_match[] = {
+ { .compatible = "fsl,ls1046a-pcie-ep", .data = &ls1_ep_drvdata },
+ { .compatible = "fsl,ls1088a-pcie-ep", .data = &ls2_ep_drvdata },
+ { .compatible = "fsl,ls2088a-pcie-ep", .data = &ls2_ep_drvdata },
+ { },
};

static int __init ls_add_pcie_ep(struct ls_pcie_ep *pcie, @@ -98,7
+134,7 @@ static int __init ls_add_pcie_ep(struct ls_pcie_ep *pcie,
int ret;

ep = &pci->ep;
- ep->ops = &pcie_ep_ops;
+ ep->ops = pcie->drvdata->ops;

res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
"addr_space");
if (!res)
@@ -137,14 +173,11 @@ static int __init ls_pcie_ep_probe(struct
platform_device *pdev)
if (!ls_epc)
return -ENOMEM;

- dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM,
"regs");
- pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base);
- if (IS_ERR(pci->dbi_base))
- return PTR_ERR(pci->dbi_base);
+ pcie->drvdata = of_device_get_match_data(dev);

- pci->dbi_base2 = pci->dbi_base + PCIE_DBI2_OFFSET;
pci->dev = dev;
- pci->ops = &ls_pcie_ep_ops;
+ pci->ops = pcie->drvdata->dw_pcie_ops;
+
pcie->pci = pci;

ls_epc->linkup_notifier = false,
@@ -152,6 +185,13 @@ static int __init ls_pcie_ep_probe(struct
platform_device *pdev)

pcie->ls_epc = ls_epc;

+ dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM,
"regs");
+ pci->dbi_base = devm_pci_remap_cfg_resource(dev, dbi_base);
+ if (IS_ERR(pci->dbi_base))
+ return PTR_ERR(pci->dbi_base);
+
+ pci->dbi_base2 = pci->dbi_base + PCIE_DBI2_OFFSET;
+
platform_set_drvdata(pdev, pcie);

ret = ls_add_pcie_ep(pcie, pdev);
--
2.9.5


---
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