Hi Prabhakar-san,
Thank you for the patch!
I'm sorry I should have mentioned on previous email. But, I have some comments.
> From: Lad Prabhakar, Sent: Sunday, April 19, 2020 10:27 PM
>
> Add support for R-Car PCIe controller to work in endpoint mode.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
<snip>
> +static int rcar_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 interrupts)
> +{
> + struct rcar_pcie_endpoint *ep = epc_get_drvdata(epc);
> + struct rcar_pcie *pcie = &ep->pcie;
> + u32 flags;
> +
> + flags = rcar_pci_read_reg(pcie, MSICAP(fn));
The argument of MSICAP() should be 0. Otherwise, if the fn is 1 or more,
the code reads a wrong register.
> + flags |= interrupts << MSICAP0_MMESCAP_OFFSET;
> + rcar_pci_write_reg(pcie, flags, MSICAP(fn));
Same here about MSICAP().
> +
> + return 0;
> +}
> +
> +static int rcar_pcie_ep_get_msi(struct pci_epc *epc, u8 fn)
> +{
> + struct rcar_pcie_endpoint *ep = epc_get_drvdata(epc);
> + struct rcar_pcie *pcie = &ep->pcie;
> + u32 flags;
> +
> + flags = rcar_pci_read_reg(pcie, MSICAP(fn));
Same here about MSICAP().
> + if (!(flags & MSICAP0_MSIE))
> + return -EINVAL;
> +
> + return ((flags & MSICAP0_MMENUM_MASK) >> MSICAP0_MMENUM_OFFSET);
> +}
> +
> +static int rcar_pcie_ep_map_addr(struct pci_epc *epc, u8 fn,
> + phys_addr_t addr, u64 pci_addr, size_t size)
> +{
> + struct rcar_pcie_endpoint *ep = epc_get_drvdata(epc);
> + struct rcar_pcie *pcie = &ep->pcie;
> + struct resource res;
> + int window;
> + int err;
> +
> + /* check if we have a link. */
> + err = rcar_pcie_wait_for_dl(pcie);
> + if (err) {
> + dev_err(pcie->dev, "link not up\n");
> + return err;
> + }
> +
> + window = rcar_pcie_ep_get_window(ep, addr);
> + if (window < 0) {
> + dev_err(pcie->dev, "failed to get corresponding window\n");
> + return -EINVAL;
> + }
> +
> + memset(&res, 0x0, sizeof(res));
> + res.start = pci_addr;
> + res.end = pci_addr + size - 1;
> + res.flags = IORESOURCE_MEM;
> +
> + rcar_pcie_set_outbound(pcie, window, &res);
> +
> + ep->ob_mapped_addr[window] = addr;
> +
> + return 0;
> +}
> +
> +static void rcar_pcie_ep_unmap_addr(struct pci_epc *epc, u8 fn,
> + phys_addr_t addr)
> +{
> + struct rcar_pcie_endpoint *ep = epc_get_drvdata(epc);
> + struct resource res;
> + int idx;
> +
> + for (idx = 0; idx < ep->num_ob_windows; idx++)
> + if (ep->ob_mapped_addr[idx] == addr)
> + break;
> +
> + if (idx >= ep->num_ob_windows)
> + return;
> +
> + memset(&res, 0x0, sizeof(res));
> + rcar_pcie_set_outbound(&ep->pcie, idx, &res);
> +
> + ep->ob_mapped_addr[idx] = 0;
> +}
> +
> +static int rcar_pcie_ep_assert_intx(struct rcar_pcie_endpoint *ep,
> + u8 fn, u8 intx)
> +{
> + struct rcar_pcie *pcie = &ep->pcie;
> + u32 val;
> +
> + val = rcar_pci_read_reg(pcie, PCIEMSITXR);
> + if ((val & PCI_MSI_FLAGS_ENABLE)) {
> + dev_err(pcie->dev, "MSI is enabled, cannot assert INTx\n");
> + return -EINVAL;
> + }
> +
> + val = rcar_pci_read_reg(pcie, PCICONF(1));
> + if ((val & INTDIS)) {
> + dev_err(pcie->dev, "INTx message transmission is disabled\n");
> + return -EINVAL;
> + }
> +
> + val = rcar_pci_read_reg(pcie, PCIEINTXR);
> + if ((val & ASTINTX)) {
> + dev_err(pcie->dev, "INTx is already asserted\n");
> + return -EINVAL;
> + }
> +
> + val |= ASTINTX;
> + rcar_pci_write_reg(pcie, val, PCIEINTXR);
> + mdelay(1);
Since pci_epc_raise_irq() calls mutex_lock() and then this function,
we can assume this function also can sleep. And, according to
Documentation/timers/timers-howto.rst, we should use
usleep_range(1000, 1000) instead of mdelay(1).
> + val = rcar_pci_read_reg(pcie, PCIEINTXR);
> + val &= ~ASTINTX;
> + rcar_pci_write_reg(pcie, val, PCIEINTXR);
> +
> + return 0;
> +}
> +
> +static int rcar_pcie_ep_assert_msi(struct rcar_pcie *pcie,
> + u8 fn, u8 interrupt_num)
> +{
> + u16 msi_count;
> + u32 val;
> +
> + /* Check MSI enable bit */
> + val = rcar_pci_read_reg(pcie, MSICAP(fn));
Same here about MSICAP().
> + if (!(val & MSICAP0_MSIE))
> + return -EINVAL;
> +
> + /* Get MSI numbers from MME */
> + msi_count = ((val & MSICAP0_MMENUM_MASK) >> MSICAP0_MMENUM_OFFSET);
> + msi_count = 1 << msi_count;
> +
> + if (!interrupt_num || interrupt_num > msi_count)
> + return -EINVAL;
> +
> + val = rcar_pci_read_reg(pcie, PCIEMSITXR);
> + rcar_pci_write_reg(pcie, val | (interrupt_num - 1), PCIEMSITXR);
> +
> + return 0;
> +}
<snip>
> diff --git a/drivers/pci/controller/pcie-rcar.h b/drivers/pci/controller/pcie-rcar.h
> index cec7768b4725..0fbeff3d7b78 100644
> --- a/drivers/pci/controller/pcie-rcar.h
> +++ b/drivers/pci/controller/pcie-rcar.h
> @@ -17,6 +17,7 @@
> #define PCIECDR 0x000020
> #define PCIEMSR 0x000028
> #define PCIEINTXR 0x000400
> +#define ASTINTX BIT(16)
> #define PCIEPHYSR 0x0007f0
> #define PHYRDY BIT(0)
> #define PCIEMSITXR 0x000840
> @@ -55,12 +56,20 @@
>
> /* Configuration */
> #define PCICONF(x) (0x010000 + ((x) * 0x4))
> +#define INTDIS BIT(10)
> #define PMCAP(x) (0x010040 + ((x) * 0x4))
> +#define MSICAP(x) (0x010050 + ((x) * 0x4))
> +#define MSICAP0_MSIE BIT(16)
> +#define MSICAP0_MMESCAP_OFFSET 17
> +#define MSICAP0_MMENUM_OFFSET 20
> +#define MSICAP0_MMENUM_MASK GENMASK(22, 20)
s/MSICAP0_MMENUM/MSICAP0_MMESE/ ?
Best regards,
Yoshihiro Shimoda
> #define EXPCAP(x) (0x010070 + ((x) * 0x4))
> #define VCCAP(x) (0x010100 + ((x) * 0x4))
>
> /* link layer */
> +#define IDSETR0 0x011000
> #define IDSETR1 0x011004
> +#define SUBIDSETR 0x011024
> #define TLCTLR 0x011048
> #define MACSR 0x011054
> #define SPCHGFIN BIT(4)
> --
> 2.17.1
