lkml.org 
[lkml]   [2019]   [Feb]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
SubjectRe: [PATCH v5 1/3] PCI: altera: Add Stratix 10 PCIe support
From
Date
On Wed, 2019-02-27 at 17:38 +0000, Lorenzo Pieralisi wrote:
> On Tue, Feb 26, 2019 at 05:15:46PM +0800, Ley Foon Tan wrote:
> >
> > Add PCIe Root Port support for Stratix 10 device.
> >
> > Main differences compare with PCIe Root Port IP on Cyclone V
> > and Arria 10 devices:
> >
> > - HIP interface to access Root Port configuration register.
> > - TLP programming flow:
> >   - One REG0 register
> >   - Don't need to check alignment
> >
> > Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
> > ---
> >  drivers/pci/controller/pcie-altera.c | 266
> > ++++++++++++++++++++++++---
> >  1 file changed, 242 insertions(+), 24 deletions(-)
> >
> > diff --git a/drivers/pci/controller/pcie-altera.c
> > b/drivers/pci/controller/pcie-altera.c
> > index 7d05e51205b3..b3c05f2f309b 100644
> > --- a/drivers/pci/controller/pcie-altera.c
> > +++ b/drivers/pci/controller/pcie-altera.c
> > @@ -11,6 +11,7 @@
> >  #include <linux/irqchip/chained_irq.h>
> >  #include <linux/init.h>
> >  #include <linux/of_address.h>
> > +#include <linux/of_device.h>
> >  #include <linux/of_irq.h>
> >  #include <linux/of_pci.h>
> >  #include <linux/pci.h>
> > @@ -37,7 +38,12 @@
> >  #define RP_LTSSM_MASK 0x1f
> >  #define LTSSM_L0 0xf
> >  
> > -#define PCIE_CAP_OFFSET 0x80
> > +#define S10_RP_TX_CNTRL 0x2004
> > +#define S10_RP_RXCPL_REG 0x2008
> > +#define S10_RP_RXCPL_STATUS 0x200C
> > +#define S10_RP_CFG_ADDR(pcie, reg) \
> > + (((pcie)->hip_base) + (reg) + (1 << 20))
> > +
> >  /* TLP configuration type 0 and 1 */
> >  #define TLP_FMTTYPE_CFGRD0 0x04 /*
> > Configuration Read Type 0 */
> >  #define TLP_FMTTYPE_CFGWR0 0x44 /*
> > Configuration Write Type 0 */
> > @@ -49,18 +55,19 @@
> >  #define RP_DEVFN 0
> >  #define TLP_REQ_ID(bus, devfn) (((bus) << 8) |
> > (devfn))
> >  #define TLP_CFGRD_DW0(pcie, bus)
> > \
> > -    ((((bus == pcie->root_bus_nr) ? TLP_FMTTYPE_CFGRD0
> > \
> > -     : TLP_FMTTYPE_CFGRD1) << 24) |
> > \
> > -     TLP_PAYLOAD_SIZE)
> > + ((((bus == pcie->root_bus_nr) ? pcie->pcie_data->cfgrd0
> > \
> > + : pcie->pcie_data->cfgrd1) << 24)
> > | \
> > + TLP_PAYLOAD_SIZE)
> >  #define TLP_CFGWR_DW0(pcie, bus)
> > \
> > -    ((((bus == pcie->root_bus_nr) ? TLP_FMTTYPE_CFGWR0
> > \
> > -     : TLP_FMTTYPE_CFGWR1) << 24) |
> > \
> > -     TLP_PAYLOAD_SIZE)
> > + ((((bus == pcie->root_bus_nr) ? pcie->pcie_data->cfgwr0
> > \
> > + : pcie->pcie_data->cfgwr1) << 24)
> > | \
> > + TLP_PAYLOAD_SIZE)
> >  #define TLP_CFG_DW1(pcie, tag, be) \
> > -    (((TLP_REQ_ID(pcie->root_bus_nr,  RP_DEVFN)) << 16) | (tag <<
> > 8) | (be))
> > + (((TLP_REQ_ID(pcie->root_bus_nr,  RP_DEVFN)) << 16) | (tag
> > << 8) | (be))
> >  #define TLP_CFG_DW2(bus, devfn, offset) \
> >   (((bus) << 24) | ((devfn) << 16) |
> > (offset))
> >  #define TLP_COMP_STATUS(s) (((s) >> 13) & 7)
> > +#define TLP_BYTE_COUNT(s) (((s) >> 0) & 0xfff)
> >  #define TLP_HDR_SIZE 3
> >  #define TLP_LOOP 500
> >  
> > @@ -69,14 +76,47 @@
> >  
> >  #define DWORD_MASK 3
> >  
> > +#define S10_TLP_FMTTYPE_CFGRD0 0x05
> > +#define S10_TLP_FMTTYPE_CFGRD1 0x04
> > +#define S10_TLP_FMTTYPE_CFGWR0 0x45
> > +#define S10_TLP_FMTTYPE_CFGWR1 0x44
> > +
> > +enum altera_pcie_version {
> > + ALTERA_PCIE_V1 = 0,
> > + ALTERA_PCIE_V2,
> > +};
> > +
> >  struct altera_pcie {
> >   struct platform_device *pdev;
> > - void __iomem *cra_base; /* DT Cra */
> > + void __iomem *cra_base;
> > + void __iomem *hip_base;
> >   int irq;
> >   u8 root_bus_nr;
> >   struct irq_domain *irq_domain;
> >   struct resource bus_range;
> >   struct list_head resources;
> > + const struct altera_pcie_data *pcie_data;
> > +};
> > +
> > +struct altera_pcie_ops {
> > + int (*tlp_read_pkt)(struct altera_pcie *pcie, u32 *value);
> > + void (*tlp_write_pkt)(struct altera_pcie *pcie, u32
> > *headers,
> > +       u32 data, bool align);
> > + bool (*get_link_status)(struct altera_pcie *pcie);
> > + int (*rp_read_cfg)(struct altera_pcie *pcie, int where,
> > +    int size, u32 *value);
> > + int (*rp_write_cfg)(struct altera_pcie *pcie, u8 busno,
> > +     int where, int size, u32 value);
> > +};
> > +
> > +struct altera_pcie_data {
> > + const struct altera_pcie_ops *ops;
> > + enum altera_pcie_version version;
> > + u32 cap_offset; /* PCIe capability
> > structure register offset */
> > + u32 cfgrd0;
> > + u32 cfgrd1;
> > + u32 cfgwr0;
> > + u32 cfgwr1;
> >  };
> >  
> >  struct tlp_rp_regpair_t {
> > @@ -101,6 +141,15 @@ static bool altera_pcie_link_up(struct
> > altera_pcie *pcie)
> >   return !!((cra_readl(pcie, RP_LTSSM) & RP_LTSSM_MASK) ==
> > LTSSM_L0);
> >  }
> >  
> > +static bool s10_altera_pcie_link_up(struct altera_pcie *pcie)
> > +{
> > + void __iomem *addr = S10_RP_CFG_ADDR(pcie,
> > +    pcie->pcie_data->cap_offset +
> > +    PCI_EXP_LNKSTA);
> > +
> > + return !!(readw(addr) & PCI_EXP_LNKSTA_DLLLA);
> > +}
> > +
> >  /*
> >   * Altera PCIe port uses BAR0 of RC's configuration space as the
> > translation
> >   * from PCI bus to native BUS.  Entire DDR region is mapped into
> > PCIe space
> > @@ -128,12 +177,18 @@ static void tlp_write_tx(struct altera_pcie
> > *pcie,
> >   cra_writel(pcie, tlp_rp_regdata->ctrl, RP_TX_CNTRL);
> >  }
> >  
> > +static void s10_tlp_write_tx(struct altera_pcie *pcie, u32 reg0,
> > u32 ctrl)
> > +{
> > + cra_writel(pcie, reg0, RP_TX_REG0);
> > + cra_writel(pcie, ctrl, S10_RP_TX_CNTRL);
> > +}
> > +
> >  static bool altera_pcie_valid_device(struct altera_pcie *pcie,
> >        struct pci_bus *bus, int dev)
> >  {
> >   /* If there is no link, then there is no device */
> >   if (bus->number != pcie->root_bus_nr) {
> > - if (!altera_pcie_link_up(pcie))
> > + if (!pcie->pcie_data->ops->get_link_status(pcie))
> >   return false;
> >   }
> >  
> > @@ -183,6 +238,49 @@ static int tlp_read_packet(struct altera_pcie
> > *pcie, u32 *value)
> >   return PCIBIOS_DEVICE_NOT_FOUND;
> >  }
> >  
> > +static int s10_tlp_read_packet(struct altera_pcie *pcie, u32
> > *value)
> > +{
> > + int i;
> > + u32 ctrl;
> > + u32 comp_status;
> > + u32 dw[4];
> > + u32 count = 0;
> > +
> > + for (i = 0; i < TLP_LOOP; i++) {
> > + ctrl = cra_readl(pcie, S10_RP_RXCPL_STATUS);
> > + if (!(ctrl & RP_RXCPL_SOP))
> > + continue;
> > +
> > + /* Read first DW */
> > + dw[count++] = cra_readl(pcie, S10_RP_RXCPL_REG);
> Maybe I still do not understand it, but why this is not:
>
> dw[0] = cra_readl(pcie, S10_RP_RXCPL_REG);
>
> and
>
> count = 1;
>
> above ?
We can do this way. Will update this.
>
> >
> > +
> > + /* Poll for EOP */
> > + for (i = 0; i < TLP_LOOP; i++) {
> > + if (count >= ARRAY_SIZE(dw))
> Can't this check be part of the loop condition ? And should not
> we get out of this function when this inner loop terminate ?
Yes, we can add this check part of loop condition. Will update this.
>
> >
> > + return PCIBIOS_DEVICE_NOT_FOUND;
> > +
> > + ctrl = cra_readl(pcie,
> > S10_RP_RXCPL_STATUS);
> > + dw[count++] = cra_readl(pcie,
> > S10_RP_RXCPL_REG);
> > + if (ctrl & RP_RXCPL_EOP) {
> > + comp_status =
> > TLP_COMP_STATUS(dw[1]);
> > + if (comp_status)
> > + return
> > PCIBIOS_DEVICE_NOT_FOUND;
> > +
> > + if (value &&
> > +     TLP_BYTE_COUNT(dw[1]) ==
> > sizeof(u32) &&
> > +     count == 4)
> > + *value = dw[3];
> > +
> > + return PCIBIOS_SUCCESSFUL;
> > + }
> > + }
> > +
> > + udelay(5);
> When should this delay be executed ? If we get here should not we
> bail
> out of the loop ?
Good catch. I have some changes on this routine previously and missed
out this. This udelay should move to code above when polling for start
of packet.
if (!(ctrl & RP_RXCPL_SOP)) {
udelay(5);
continue;
}

>
> I would like to try to merge these patches but I need a clarification
> on this code first, I can update the code myself for the sake of
> making
> progress.
>
> Lorenzo
Will send out new revision with changes above for you to merge.

Thanks.

Regards
Ley Foon
>
> >
> > + }
> > +
> > + return PCIBIOS_DEVICE_NOT_FOUND;
> > +}
> > +
> >  static void tlp_write_packet(struct altera_pcie *pcie, u32
> > *headers,
> >        u32 data, bool align)
> >  {
> > @@ -210,6 +308,15 @@ static void tlp_write_packet(struct
> > altera_pcie *pcie, u32 *headers,
> >   tlp_write_tx(pcie, &tlp_rp_regdata);
> >  }
> >  
> > +static void s10_tlp_write_packet(struct altera_pcie *pcie, u32
> > *headers,
> > +  u32 data, bool dummy)
> > +{
> > + s10_tlp_write_tx(pcie, headers[0], RP_TX_SOP);
> > + s10_tlp_write_tx(pcie, headers[1], 0);
> > + s10_tlp_write_tx(pcie, headers[2], 0);
> > + s10_tlp_write_tx(pcie, data, RP_TX_EOP);
> > +}
> > +
> >  static int tlp_cfg_dword_read(struct altera_pcie *pcie, u8 bus,
> > u32 devfn,
> >         int where, u8 byte_en, u32 *value)
> >  {
> > @@ -219,9 +326,9 @@ static int tlp_cfg_dword_read(struct
> > altera_pcie *pcie, u8 bus, u32 devfn,
> >   headers[1] = TLP_CFG_DW1(pcie, TLP_READ_TAG, byte_en);
> >   headers[2] = TLP_CFG_DW2(bus, devfn, where);
> >  
> > - tlp_write_packet(pcie, headers, 0, false);
> > + pcie->pcie_data->ops->tlp_write_pkt(pcie, headers, 0,
> > false);
> >  
> > - return tlp_read_packet(pcie, value);
> > + return pcie->pcie_data->ops->tlp_read_pkt(pcie, value);
> >  }
> >  
> >  static int tlp_cfg_dword_write(struct altera_pcie *pcie, u8 bus,
> > u32 devfn,
> > @@ -236,11 +343,13 @@ static int tlp_cfg_dword_write(struct
> > altera_pcie *pcie, u8 bus, u32 devfn,
> >  
> >   /* check alignment to Qword */
> >   if ((where & 0x7) == 0)
> > - tlp_write_packet(pcie, headers, value, true);
> > + pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
> > +     value, true);
> >   else
> > - tlp_write_packet(pcie, headers, value, false);
> > + pcie->pcie_data->ops->tlp_write_pkt(pcie, headers,
> > +     value, false);
> >  
> > - ret = tlp_read_packet(pcie, NULL);
> > + ret = pcie->pcie_data->ops->tlp_read_pkt(pcie, NULL);
> >   if (ret != PCIBIOS_SUCCESSFUL)
> >   return ret;
> >  
> > @@ -254,6 +363,53 @@ static int tlp_cfg_dword_write(struct
> > altera_pcie *pcie, u8 bus, u32 devfn,
> >   return PCIBIOS_SUCCESSFUL;
> >  }
> >  
> > +static int s10_rp_read_cfg(struct altera_pcie *pcie, int where,
> > +    int size, u32 *value)
> > +{
> > + void *addr = S10_RP_CFG_ADDR(pcie, where);
> > +
> > + switch (size) {
> > + case 1:
> > + *value = readb(addr);
> > + break;
> > + case 2:
> > + *value = readw(addr);
> > + break;
> > + default:
> > + *value = readl(addr);
> > + break;
> > + }
> > +
> > + return PCIBIOS_SUCCESSFUL;
> > +}
> > +
> > +static int s10_rp_write_cfg(struct altera_pcie *pcie, u8 busno,
> > +     int where, int size, u32 value)
> > +{
> > + void *addr = S10_RP_CFG_ADDR(pcie, where);
> > +
> > + switch (size) {
> > + case 1:
> > + writeb(value, addr);
> > + break;
> > + case 2:
> > + writew(value, addr);
> > + break;
> > + default:
> > + writel(value, addr);
> > + break;
> > + }
> > +
> > + /*
> > +  * Monitor changes to PCI_PRIMARY_BUS register on root
> > port
> > +  * and update local copy of root bus number accordingly.
> > +  */
> > + if (busno == pcie->root_bus_nr && where ==
> > PCI_PRIMARY_BUS)
> > + pcie->root_bus_nr = value & 0xff;
> > +
> > + return PCIBIOS_SUCCESSFUL;
> > +}
> > +
> >  static int _altera_pcie_cfg_read(struct altera_pcie *pcie, u8
> > busno,
> >    unsigned int devfn, int where,
> > int size,
> >    u32 *value)
> > @@ -262,6 +418,10 @@ static int _altera_pcie_cfg_read(struct
> > altera_pcie *pcie, u8 busno,
> >   u32 data;
> >   u8 byte_en;
> >  
> > + if (busno == pcie->root_bus_nr && pcie->pcie_data->ops-
> > >rp_read_cfg)
> > + return pcie->pcie_data->ops->rp_read_cfg(pcie,
> > where,
> > +  size,
> > value);
> > +
> >   switch (size) {
> >   case 1:
> >   byte_en = 1 << (where & 3);
> > @@ -302,6 +462,10 @@ static int _altera_pcie_cfg_write(struct
> > altera_pcie *pcie, u8 busno,
> >   u32 shift = 8 * (where & 3);
> >   u8 byte_en;
> >  
> > + if (busno == pcie->root_bus_nr && pcie->pcie_data->ops-
> > >rp_write_cfg)
> > + return pcie->pcie_data->ops->rp_write_cfg(pcie,
> > busno,
> > +      where, size,
> > value);
> > +
> >   switch (size) {
> >   case 1:
> >   data32 = (value & 0xff) << shift;
> > @@ -365,7 +529,8 @@ static int altera_read_cap_word(struct
> > altera_pcie *pcie, u8 busno,
> >   int ret;
> >  
> >   ret = _altera_pcie_cfg_read(pcie, busno, devfn,
> > -     PCIE_CAP_OFFSET + offset,
> > sizeof(*value),
> > +     pcie->pcie_data->cap_offset +
> > offset,
> > +     sizeof(*value),
> >       &data);
> >   *value = data;
> >   return ret;
> > @@ -375,7 +540,8 @@ static int altera_write_cap_word(struct
> > altera_pcie *pcie, u8 busno,
> >    unsigned int devfn, int offset,
> > u16 value)
> >  {
> >   return _altera_pcie_cfg_write(pcie, busno, devfn,
> > -       PCIE_CAP_OFFSET + offset,
> > sizeof(value),
> > +       pcie->pcie_data->cap_offset
> > + offset,
> > +       sizeof(value),
> >         value);
> >  }
> >  
> > @@ -403,7 +569,7 @@ static void altera_wait_link_retrain(struct
> > altera_pcie *pcie)
> >   /* Wait for link is up */
> >   start_jiffies = jiffies;
> >   for (;;) {
> > - if (altera_pcie_link_up(pcie))
> > + if (pcie->pcie_data->ops->get_link_status(pcie))
> >   break;
> >  
> >   if (time_after(jiffies, start_jiffies +
> > LINK_UP_TIMEOUT)) {
> > @@ -418,7 +584,7 @@ static void altera_pcie_retrain(struct
> > altera_pcie *pcie)
> >  {
> >   u16 linkcap, linkstat, linkctl;
> >  
> > - if (!altera_pcie_link_up(pcie))
> > + if (!pcie->pcie_data->ops->get_link_status(pcie))
> >   return;
> >  
> >   /*
> > @@ -540,12 +706,20 @@ static int altera_pcie_parse_dt(struct
> > altera_pcie *pcie)
> >   struct device *dev = &pcie->pdev->dev;
> >   struct platform_device *pdev = pcie->pdev;
> >   struct resource *cra;
> > + struct resource *hip;
> >  
> >   cra = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> > "Cra");
> >   pcie->cra_base = devm_ioremap_resource(dev, cra);
> >   if (IS_ERR(pcie->cra_base))
> >   return PTR_ERR(pcie->cra_base);
> >  
> > + if (pcie->pcie_data->version == ALTERA_PCIE_V2) {
> > + hip = platform_get_resource_byname(pdev,
> > IORESOURCE_MEM, "Hip");
> > + pcie->hip_base = devm_ioremap_resource(&pdev->dev,
> > hip);
> > + if (IS_ERR(pcie->hip_base))
> > + return PTR_ERR(pcie->hip_base);
> > + }
> > +
> >   /* setup IRQ */
> >   pcie->irq = platform_get_irq(pdev, 0);
> >   if (pcie->irq < 0) {
> > @@ -562,6 +736,48 @@ static void altera_pcie_host_init(struct
> > altera_pcie *pcie)
> >   altera_pcie_retrain(pcie);
> >  }
> >  
> > +static const struct altera_pcie_ops altera_pcie_ops_1_0 = {
> > + .tlp_read_pkt = tlp_read_packet,
> > + .tlp_write_pkt = tlp_write_packet,
> > + .get_link_status = altera_pcie_link_up,
> > +};
> > +
> > +static const struct altera_pcie_ops altera_pcie_ops_2_0 = {
> > + .tlp_read_pkt = s10_tlp_read_packet,
> > + .tlp_write_pkt = s10_tlp_write_packet,
> > + .get_link_status = s10_altera_pcie_link_up,
> > + .rp_read_cfg = s10_rp_read_cfg,
> > + .rp_write_cfg = s10_rp_write_cfg,
> > +};
> > +
> > +static const struct altera_pcie_data altera_pcie_1_0_data = {
> > + .ops = &altera_pcie_ops_1_0,
> > + .cap_offset = 0x80,
> > + .version = ALTERA_PCIE_V1,
> > + .cfgrd0 = TLP_FMTTYPE_CFGRD0,
> > + .cfgrd1 = TLP_FMTTYPE_CFGRD1,
> > + .cfgwr0 = TLP_FMTTYPE_CFGWR0,
> > + .cfgwr1 = TLP_FMTTYPE_CFGWR1,
> > +};
> > +
> > +static const struct altera_pcie_data altera_pcie_2_0_data = {
> > + .ops = &altera_pcie_ops_2_0,
> > + .version = ALTERA_PCIE_V2,
> > + .cap_offset = 0x70,
> > + .cfgrd0 = S10_TLP_FMTTYPE_CFGRD0,
> > + .cfgrd1 = S10_TLP_FMTTYPE_CFGRD1,
> > + .cfgwr0 = S10_TLP_FMTTYPE_CFGWR0,
> > + .cfgwr1 = S10_TLP_FMTTYPE_CFGWR1,
> > +};
> > +
> > +static const struct of_device_id altera_pcie_of_match[] = {
> > + {.compatible = "altr,pcie-root-port-1.0",
> > +  .data = &altera_pcie_1_0_data },
> > + {.compatible = "altr,pcie-root-port-2.0",
> > +  .data = &altera_pcie_2_0_data },
> > + {},
> > +};
> > +
> >  static int altera_pcie_probe(struct platform_device *pdev)
> >  {
> >   struct device *dev = &pdev->dev;
> > @@ -570,6 +786,7 @@ static int altera_pcie_probe(struct
> > platform_device *pdev)
> >   struct pci_bus *child;
> >   struct pci_host_bridge *bridge;
> >   int ret;
> > + const struct of_device_id *match;
> >  
> >   bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
> >   if (!bridge)
> > @@ -578,6 +795,12 @@ static int altera_pcie_probe(struct
> > platform_device *pdev)
> >   pcie = pci_host_bridge_priv(bridge);
> >   pcie->pdev = pdev;
> >  
> > + match = of_match_device(altera_pcie_of_match, &pdev->dev);
> > + if (!match)
> > + return -ENODEV;
> > +
> > + pcie->pcie_data = match->data;
> > +
> >   ret = altera_pcie_parse_dt(pcie);
> >   if (ret) {
> >   dev_err(dev, "Parsing DT failed\n");
> > @@ -628,11 +851,6 @@ static int altera_pcie_probe(struct
> > platform_device *pdev)
> >   return ret;
> >  }
> >  
> > -static const struct of_device_id altera_pcie_of_match[] = {
> > - { .compatible = "altr,pcie-root-port-1.0", },
> > - {},
> > -};
> > -
> >  static struct platform_driver altera_pcie_driver = {
> >   .probe = altera_pcie_probe,
> >   .driver = {

\
 
 \ /
  Last update: 2019-02-28 03:15    [W:0.059 / U:11.284 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site