Hi Rob, Thanks a lot for your comments! > -----Original Message----- > From: Rob Herring <robh@xxxxxxxxxx> > Sent: 2020年9月15日 9:30 > To: Z.q. Hou <zhiqiang.hou@xxxxxxx> > Cc: linux-pci@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx; bhelgaas@xxxxxxxxxx; > shawnguo@xxxxxxxxxx; Leo Li <leoyang.li@xxxxxxx>; > lorenzo.pieralisi@xxxxxxx; gustavo.pimentel@xxxxxxxxxxxx; M.h. Lian > <minghuan.lian@xxxxxxx>; Mingkai Hu <mingkai.hu@xxxxxxx>; Roy Zang > <roy.zang@xxxxxxx> > Subject: Re: [PATCH 7/7] PCI: layerscape: Add power management support > > On Mon, Sep 07, 2020 at 01:38:01PM +0800, Zhiqiang Hou wrote: > > From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx> > > > > Add PME_Turn_Off/PME_TO_Ack handshake sequence, and finally put the > > PCIe controller into D3 state after the L2/L3 ready state transition > > process completion. > > > > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx> > > --- > > drivers/pci/controller/dwc/pci-layerscape.c | 384 > ++++++++++++++++++- > > drivers/pci/controller/dwc/pcie-designware.h | 1 + > > 2 files changed, 383 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/pci/controller/dwc/pci-layerscape.c > > b/drivers/pci/controller/dwc/pci-layerscape.c > > index be404c16bcbe..ca9ea07f77c1 100644 > > --- a/drivers/pci/controller/dwc/pci-layerscape.c > > +++ b/drivers/pci/controller/dwc/pci-layerscape.c > > @@ -3,13 +3,16 @@ > > * PCIe host controller driver for Freescale Layerscape SoCs > > * > > * Copyright (C) 2014 Freescale Semiconductor. > > + * Copyright 2020 NXP > > * > > * Author: Minghuan Lian <Minghuan.Lian@xxxxxxxxxxxxx> > > */ > > > > +#include <linux/delay.h> > > #include <linux/kernel.h> > > #include <linux/interrupt.h> > > #include <linux/init.h> > > +#include <linux/iopoll.h> > > #include <linux/of_pci.h> > > #include <linux/of_platform.h> > > #include <linux/of_irq.h> > > @@ -27,17 +30,66 @@ > > #define PCIE_ABSERR 0x8d0 /* Bridge Slave Error Response > Register */ > > #define PCIE_ABSERR_SETTING 0x9401 /* Forward error of > non-posted request */ > > > > +#define PCIE_PM_SCR 0x44 > > +#define PCIE_PM_SCR_PMEPS_D0 0x0 > > +#define PCIE_PM_SCR_PMEPS_D3 0x3 > > + > > +#define PCIE_LNKCTL 0x80 /* PCIe link ctrl Register */ > > Use the common defines. > OK, will change in next version. > > > + > > +/* PF Message Command Register */ > > +#define LS_PCIE_PF_MCR 0x2c > > +#define PF_MCR_PTOMR BIT(0) > > +#define PF_MCR_EXL2S BIT(1) > > + > > +/* LS1021A PEXn PM Write Control Register */ > > +#define SCFG_PEXPMWRCR(idx) (0x5c + (idx) * 0x64) > > +#define PMXMTTURNOFF BIT(31) > > +#define SCFG_PEXSFTRSTCR 0x190 > > +#define PEXSR(idx) BIT(idx) > > + > > +/* LS1043A PEX PME control register */ > > +#define SCFG_PEXPMECR 0x144 > > +#define PEXPME(idx) BIT(31 - (idx) * 4) > > + > > +/* LS1043A PEX LUT debug register */ > > +#define LS_PCIE_LDBG 0x7fc > > +#define LDBG_SR BIT(30) > > +#define LDBG_WE BIT(31) > > + > > #define PCIE_IATU_NUM 6 > > > > +#define LS_PCIE_IS_L2(v) \ > > + (((v) & PORT_LOGIC_LTSSM_STATE_MASK) == > PORT_LOGIC_LTSSM_STATE_L2) > > + > > +struct ls_pcie; > > + > > +struct ls_pcie_host_pm_ops { > > + int (*pm_init)(struct ls_pcie *pcie); > > + void (*send_turn_off_message)(struct ls_pcie *pcie); > > + void (*exit_from_l2)(struct ls_pcie *pcie); }; > > + > > struct ls_pcie_drvdata { > > + const u32 pf_off; > > + const u32 lut_off; > > const struct dw_pcie_host_ops *ops; > > + const struct ls_pcie_host_pm_ops *pm_ops; > > }; > > > > struct ls_pcie { > > struct dw_pcie *pci; > > const struct ls_pcie_drvdata *drvdata; > > + void __iomem *pf_base; > > + void __iomem *lut_base; > > + bool big_endian; > > + bool ep_presence; > > + bool pm_support; > > + struct regmap *scfg; > > + int index; > > }; > > > > +#define ls_pcie_lut_readl_addr(addr) ls_pcie_lut_readl(pcie, addr) > > +#define ls_pcie_pf_readl_addr(addr) ls_pcie_pf_readl(pcie, addr) > > #define to_ls_pcie(x) dev_get_drvdata((x)->dev) > > > > static bool ls_pcie_is_bridge(struct ls_pcie *pcie) @@ -86,6 +138,208 > > @@ static void ls_pcie_fix_error_response(struct ls_pcie *pcie) > > iowrite32(PCIE_ABSERR_SETTING, pci->dbi_base + PCIE_ABSERR); } > > > > +static u32 ls_pcie_lut_readl(struct ls_pcie *pcie, u32 off) { > > + if (pcie->big_endian) > > + return ioread32be(pcie->lut_base + off); > > + > > + return ioread32(pcie->lut_base + off); } > > + > > +static void ls_pcie_lut_writel(struct ls_pcie *pcie, u32 off, u32 > > +val) { > > + if (pcie->big_endian) > > + return iowrite32be(val, pcie->lut_base + off); > > + > > + return iowrite32(val, pcie->lut_base + off); > > + > > +} > > + > > +static u32 ls_pcie_pf_readl(struct ls_pcie *pcie, u32 off) { > > + if (pcie->big_endian) > > + return ioread32be(pcie->pf_base + off); > > + > > + return ioread32(pcie->pf_base + off); } > > + > > +static void ls_pcie_pf_writel(struct ls_pcie *pcie, u32 off, u32 val) > > +{ > > + if (pcie->big_endian) > > + return iowrite32be(val, pcie->pf_base + off); > > + > > + return iowrite32(val, pcie->pf_base + off); > > + > > +} > > + > > +static void ls_pcie_send_turnoff_msg(struct ls_pcie *pcie) { > > + u32 val; > > + int ret; > > + > > + val = ls_pcie_pf_readl(pcie, LS_PCIE_PF_MCR); > > + val |= PF_MCR_PTOMR; > > + ls_pcie_pf_writel(pcie, LS_PCIE_PF_MCR, val); > > + > > + ret = readx_poll_timeout(ls_pcie_pf_readl_addr, LS_PCIE_PF_MCR, > > + val, !(val & PF_MCR_PTOMR), 100, 10000); > > + if (ret) > > + dev_info(pcie->pci->dev, "poll turn off message timeout\n"); } > > + > > +static void ls1021a_pcie_send_turnoff_msg(struct ls_pcie *pcie) { > > + u32 val; > > + > > + if (!pcie->scfg) { > > + dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n"); > > + return; > > + } > > + > > + /* Send Turn_off message */ > > + regmap_read(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), &val); > > + val |= PMXMTTURNOFF; > > + regmap_write(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), val); > > + > > + mdelay(10); > > + > > + /* Clear Turn_off message */ > > + regmap_read(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), &val); > > + val &= ~PMXMTTURNOFF; > > + regmap_write(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), val); } > > + > > +static void ls1043a_pcie_send_turnoff_msg(struct ls_pcie *pcie) { > > + u32 val; > > + > > + if (!pcie->scfg) { > > + dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n"); > > + return; > > + } > > + > > + /* Send Turn_off message */ > > + regmap_read(pcie->scfg, SCFG_PEXPMECR, &val); > > + val |= PEXPME(pcie->index); > > + regmap_write(pcie->scfg, SCFG_PEXPMECR, val); > > + > > + mdelay(10); > > + > > + /* Clear Turn_off message */ > > + regmap_read(pcie->scfg, SCFG_PEXPMECR, &val); > > + val &= ~PEXPME(pcie->index); > > + regmap_write(pcie->scfg, SCFG_PEXPMECR, val); } > > + > > +static void ls_pcie_exit_from_l2(struct ls_pcie *pcie) { > > + u32 val; > > + int ret; > > + > > + val = ls_pcie_pf_readl(pcie, LS_PCIE_PF_MCR); > > + val |= PF_MCR_EXL2S; > > + ls_pcie_pf_writel(pcie, LS_PCIE_PF_MCR, val); > > + > > + ret = readx_poll_timeout(ls_pcie_pf_readl_addr, LS_PCIE_PF_MCR, > > + val, !(val & PF_MCR_EXL2S), 100, 10000); > > + if (ret) > > + dev_info(pcie->pci->dev, "poll exit L2 state timeout\n"); } > > + > > +static void ls_pcie_retrain_link(struct ls_pcie *pcie) { > > + struct dw_pcie *pci = pcie->pci; > > + u32 val; > > + > > + val = dw_pcie_readw_dbi(pci, PCIE_LNKCTL); > > + val |= PCI_EXP_LNKCTL_RL; > > + dw_pcie_writew_dbi(pci, PCIE_LNKCTL, val); } > > + > > +static void ls1021a_pcie_exit_from_l2(struct ls_pcie *pcie) { > > + u32 val; > > + > > + regmap_read(pcie->scfg, SCFG_PEXSFTRSTCR, &val); > > + val |= PEXSR(pcie->index); > > + regmap_write(pcie->scfg, SCFG_PEXSFTRSTCR, val); > > + > > + regmap_read(pcie->scfg, SCFG_PEXSFTRSTCR, &val); > > + val &= ~PEXSR(pcie->index); > > + regmap_write(pcie->scfg, SCFG_PEXSFTRSTCR, val); > > + > > + mdelay(1); > > + > > + ls_pcie_retrain_link(pcie); > > +} > > +static void ls1043a_pcie_exit_from_l2(struct ls_pcie *pcie) { > > + u32 val; > > + > > + val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG); > > + val |= LDBG_WE; > > + ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val); > > + > > + val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG); > > + val |= LDBG_SR; > > + ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val); > > + > > + val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG); > > + val &= ~LDBG_SR; > > + ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val); > > + > > + val = ls_pcie_lut_readl(pcie, LS_PCIE_LDBG); > > + val &= ~LDBG_WE; > > + ls_pcie_lut_writel(pcie, LS_PCIE_LDBG, val); > > + > > + mdelay(1); > > + > > + ls_pcie_retrain_link(pcie); > > +} > > + > > +static int ls1021a_pcie_pm_init(struct ls_pcie *pcie) { > > + struct device *dev = pcie->pci->dev; > > + u32 index[2]; > > + int ret; > > + > > + pcie->scfg = syscon_regmap_lookup_by_phandle(dev->of_node, > > + "fsl,pcie-scfg"); > > + if (IS_ERR(pcie->scfg)) { > > + ret = PTR_ERR(pcie->scfg); > > + dev_err(dev, "No syscfg phandle specified\n"); > > + pcie->scfg = NULL; > > + return ret; > > + } > > + > > + ret = of_property_read_u32_array(dev->of_node, "fsl,pcie-scfg", > > + index, 2); > > + if (ret) { > > + pcie->scfg = NULL; > > + return ret; > > + } > > + > > + pcie->index = index[1]; > > + > > + return 0; > > +} > > + > > +static int ls_pcie_pm_init(struct ls_pcie *pcie) { > > + return 0; > > +} > > + > > +static void ls_pcie_set_dstate(struct ls_pcie *pcie, u32 dstate) { > > + struct dw_pcie *pci = pcie->pci; > > + u32 val; > > + > > + val = dw_pcie_readw_dbi(pci, PCIE_PM_SCR); > > + val &= ~PCI_PM_CTRL_STATE_MASK; > > + val |= dstate; > > + dw_pcie_writew_dbi(pci, PCIE_PM_SCR, val); } > > + > > static int ls_pcie_host_init(struct pcie_port *pp) { > > struct dw_pcie *pci = to_dw_pcie_from_pp(pp); @@ -133,20 +387,52 > @@ > > static int ls_pcie_msi_host_init(struct pcie_port *pp) > > return 0; > > } > > > > +static struct ls_pcie_host_pm_ops ls1021a_pcie_host_pm_ops = { > > + .pm_init = &ls1021a_pcie_pm_init, > > + .send_turn_off_message = &ls1021a_pcie_send_turnoff_msg, > > + .exit_from_l2 = &ls1021a_pcie_exit_from_l2, }; > > + > > +static struct ls_pcie_host_pm_ops ls1043a_pcie_host_pm_ops = { > > + .pm_init = &ls1021a_pcie_pm_init, > > + .send_turn_off_message = &ls1043a_pcie_send_turnoff_msg, > > + .exit_from_l2 = &ls1043a_pcie_exit_from_l2, }; > > + > > +static struct ls_pcie_host_pm_ops ls_pcie_host_pm_ops = { > > + .pm_init = &ls_pcie_pm_init, > > + .send_turn_off_message = &ls_pcie_send_turnoff_msg, > > + .exit_from_l2 = &ls_pcie_exit_from_l2, }; > > + > > static const struct dw_pcie_host_ops ls_pcie_host_ops = { > > .host_init = ls_pcie_host_init, > > .msi_host_init = ls_pcie_msi_host_init, }; > > > > +static const struct ls_pcie_drvdata ls1021a_drvdata = { > > + .ops = &ls_pcie_host_ops, > > + .pm_ops = &ls1021a_pcie_host_pm_ops, }; > > + > > +static const struct ls_pcie_drvdata ls1043a_drvdata = { > > + .ops = &ls_pcie_host_ops, > > + .lut_off = 0x10000, > > + .pm_ops = &ls1043a_pcie_host_pm_ops, }; > > + > > static const struct ls_pcie_drvdata layerscape_drvdata = { > > .ops = &ls_pcie_host_ops, > > + .lut_off = 0x80000, > > + .pf_off = 0xc0000, > > + .pm_ops = &ls_pcie_host_pm_ops, > > }; > > > > static const struct of_device_id ls_pcie_of_match[] = { > > { .compatible = "fsl,ls1012a-pcie", .data = &layerscape_drvdata }, > > - { .compatible = "fsl,ls1021a-pcie", .data = &layerscape_drvdata }, > > + { .compatible = "fsl,ls1021a-pcie", .data = &ls1021a_drvdata }, > > { .compatible = "fsl,ls1028a-pcie", .data = &layerscape_drvdata }, > > - { .compatible = "fsl,ls1043a-pcie", .data = &layerscape_drvdata }, > > + { .compatible = "fsl,ls1043a-pcie", .data = &ls1043a_drvdata }, > > { .compatible = "fsl,ls1046a-pcie", .data = &layerscape_drvdata }, > > { .compatible = "fsl,ls2080a-pcie", .data = &layerscape_drvdata }, > > { .compatible = "fsl,ls2085a-pcie", .data = &layerscape_drvdata }, > > @@ -170,6 +456,15 @@ static int __init ls_add_pcie_port(struct ls_pcie > *pcie) > > return ret; > > } > > > > + if (dw_pcie_link_up(pci)) { > > + dev_dbg(pci->dev, "Endpoint is present\n"); > > + pcie->ep_presence = true; > > + } > > + > > + if (pcie->drvdata->pm_ops && pcie->drvdata->pm_ops->pm_init && > > + !pcie->drvdata->pm_ops->pm_init(pcie)) > > + pcie->pm_support = true; > > + > > return 0; > > } > > > > @@ -200,6 +495,14 @@ static int __init ls_pcie_probe(struct > platform_device *pdev) > > if (IS_ERR(pci->dbi_base)) > > return PTR_ERR(pci->dbi_base); > > > > + pcie->big_endian = of_property_read_bool(dev->of_node, > > +"big-endian"); > > + > > + if (pcie->drvdata->lut_off) > > + pcie->lut_base = pci->dbi_base + pcie->drvdata->lut_off; > > + > > + if (pcie->drvdata->pf_off) > > + pcie->pf_base = pci->dbi_base + pcie->drvdata->pf_off; > > + > > if (!ls_pcie_is_bridge(pcie)) > > return -ENODEV; > > > > @@ -212,11 +515,88 @@ static int __init ls_pcie_probe(struct > platform_device *pdev) > > return 0; > > } > > > > +static bool ls_pcie_pm_check(struct ls_pcie *pcie) { > > + if (!pcie->ep_presence) { > > + dev_dbg(pcie->pci->dev, "Endpoint isn't present\n"); > > + return false; > > + } > > + > > + if (!pcie->pm_support) > > + return false; > > + > > + return true; > > +} > > + > > +#ifdef CONFIG_PM_SLEEP > > +static int ls_pcie_suspend_noirq(struct device *dev) > > Why is noirq variant needed? Most drivers don't need this. Actually all PCIe RC drivers use the noirq variant, the reason is the pci_pm_suspend_noirq() will call the pci_save_state(). Regards, Zhiqiang > > > +{ > > + struct ls_pcie *pcie = dev_get_drvdata(dev); > > + struct dw_pcie *pci = pcie->pci; > > + u32 val; > > + int ret; > > + > > + if (!ls_pcie_pm_check(pcie)) > > + return 0; > > + > > + pcie->drvdata->pm_ops->send_turn_off_message(pcie); > > + > > + /* 10ms timeout to check L2 ready */ > > + ret = readl_poll_timeout(pci->dbi_base + PCIE_PORT_DEBUG0, > > + val, LS_PCIE_IS_L2(val), 100, 10000); > > + if (ret) { > > + dev_err(dev, "PCIe link enter L2 timeout! ltssm = 0x%x\n", val); > > + return ret; > > + } > > + > > + ls_pcie_set_dstate(pcie, PCIE_PM_SCR_PMEPS_D3); > > + > > + return 0; > > +} > > + > > +static int ls_pcie_resume_noirq(struct device *dev) { > > + struct ls_pcie *pcie = dev_get_drvdata(dev); > > + struct dw_pcie *pci = pcie->pci; > > + int ret; > > + > > + if (!ls_pcie_pm_check(pcie)) > > + return 0; > > + > > + ls_pcie_set_dstate(pcie, PCIE_PM_SCR_PMEPS_D0); > > + > > + pcie->drvdata->pm_ops->exit_from_l2(pcie); > > + > > + /* delay 10ms to access EP */ > > + mdelay(10); > > + > > + ret = ls_pcie_host_init(&pci->pp); > > + if (ret) { > > + dev_err(dev, "ls_pcie_host_init failed! ret = 0x%x\n", ret); > > + return ret; > > + } > > + > > + ret = dw_pcie_wait_for_link(pci); > > + if (ret) { > > + dev_err(dev, "wait link up timeout! ret = 0x%x\n", ret); > > + return ret; > > + } > > + > > + return 0; > > +} > > +#endif /* CONFIG_PM_SLEEP */ > > + > > +static const struct dev_pm_ops ls_pcie_pm_ops = { > > + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(ls_pcie_suspend_noirq, > > + ls_pcie_resume_noirq) > > +}; > > + > > static struct platform_driver ls_pcie_driver = { > > .driver = { > > .name = "layerscape-pcie", > > .of_match_table = ls_pcie_of_match, > > .suppress_bind_attrs = true, > > + .pm = &ls_pcie_pm_ops, > > }, > > }; > > builtin_platform_driver_probe(ls_pcie_driver, ls_pcie_probe); diff > > --git a/drivers/pci/controller/dwc/pcie-designware.h > > b/drivers/pci/controller/dwc/pcie-designware.h > > index f911760dcc69..1f2fd03d1eba 100644 > > --- a/drivers/pci/controller/dwc/pcie-designware.h > > +++ b/drivers/pci/controller/dwc/pcie-designware.h > > @@ -46,6 +46,7 @@ > > #define PCIE_PORT_DEBUG0 0x728 > > #define PORT_LOGIC_LTSSM_STATE_MASK 0x1f > > #define PORT_LOGIC_LTSSM_STATE_L0 0x11 > > +#define PORT_LOGIC_LTSSM_STATE_L2 0x15 > > #define PCIE_PORT_DEBUG1 0x72C > > #define PCIE_PORT_DEBUG1_LINK_UP BIT(4) > > #define PCIE_PORT_DEBUG1_LINK_IN_TRAINING BIT(29) > > -- > > 2.17.1 > >