Re: [PATCH v7 20/20] PCI: dwc: Add Baikal-T1 PCIe controller support
From: Manivannan Sadhasivam
Date: Mon Nov 14 2022 - 02:31:57 EST
On Sun, Nov 13, 2022 at 10:13:01PM +0300, Serge Semin wrote:
> Baikal-T1 SoC is equipped with DWC PCIe v4.60a host controller. It can be
> trained to work up to Gen.3 speed over up to x4 lanes. The host controller
> is attached to the DW PCIe 3.0 PCS via the PIPE-4 interface, which in its
> turn is connected to the DWC 10G PHY. The whole system is supposed to be
> fed up with four clock sources: DBI peripheral clock, AXI application
> clocks and external PHY/core reference clock generating the 100MHz signal.
> In addition to that the platform provide a way to reset each part of the
> controller: sticky/non-sticky bits, host controller core, PIPE interface,
> PCS/PHY and Hot/Power reset signal. The driver also provides a way to
> handle the GPIO-based PERST# signal.
>
> Note due to the Baikal-T1 MMIO peculiarity we have to implement the DBI
> interface accessors which make sure the IO operations are dword-aligned.
>
> Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
>
> ---
>
> Changelog v2:
> - Rename 'syscon' property to 'baikal,bt1-syscon'.
>
> Changelog v3:
> - Use the clocks/resets handlers defined in the DW PCIe core descriptor.
> (@Rob)
> - Redefine PCI host bridge config space accessors with the generic
> pci_generic_config_read32() and pci_generic_config_write32() methods.
> (@Rob)
>
> Changelog v4:
> - Drop PCIBIOS_* macros usage. (@Rob)
> - Add "static const" to the dw_pcie_ops and dw_pcie_host_ops structure
> instances. (@Bjorn)
> - Rename bt1_pcie_dw_ops to bt1_pcie_ops. (@Bjorn)
> - Rename bt1_pcie_ops to bt1_pci_ops. (@Bjorn)
> - Use start_link/stop_link suffixes in the corresponding callbacks.
> (@Bjorn)
> - Change the get_res() method suffix to being get_resources(). (@Bjorn)
> - Change *_{add,del}_dw_port() method to *_{add,del}_port(). (@Bjorn)
> - Drop dma_coerce_mask_and_coherent() applied to the PCI host bridge
> kernel device instance. (@Bjorn)
> - Add the comment above the dma_set_mask_and_coherent() method usage
> regarding the controller eDMA feature. (@Bjorn)
> - Fix the comment above the core reset controls assertion. (@Bjorn)
> - Replace delays and timeout numeric literals with macros. (@Bjorn)
>
> Changelog v6:
> - Move the DMA-mask setup to the eDMA driver. (@Robin)
>
> Changelog v7:
> - Replace if-then-dev_err_probe-return statement with just
> return-dev_err_probe one.
> ---
> drivers/pci/controller/dwc/Kconfig | 9 +
> drivers/pci/controller/dwc/Makefile | 1 +
> drivers/pci/controller/dwc/pcie-bt1.c | 643 ++++++++++++++++++++++++++
> 3 files changed, 653 insertions(+)
> create mode 100644 drivers/pci/controller/dwc/pcie-bt1.c
>
> diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
> index 62ce3abf0f19..771b8b146623 100644
> --- a/drivers/pci/controller/dwc/Kconfig
> +++ b/drivers/pci/controller/dwc/Kconfig
> @@ -222,6 +222,15 @@ config PCIE_ARTPEC6_EP
> Enables support for the PCIe controller in the ARTPEC-6 SoC to work in
> endpoint mode. This uses the DesignWare core.
>
> +config PCIE_BT1
> + tristate "Baikal-T1 PCIe controller"
Wondering why cannot this be "PCIE_BAIKAL"? Are you sure that this same driver
cannot be reused for other Baikal SoCs in future?
> + depends on MIPS_BAIKAL_T1 || COMPILE_TEST
> + depends on PCI_MSI_IRQ_DOMAIN
> + select PCIE_DW_HOST
> + help
> + Enables support for the PCIe controller in the Baikal-T1 SoC to work
> + in host mode. It's based on the Synopsys DWC PCIe v4.60a IP-core.
> +
> config PCIE_ROCKCHIP_DW_HOST
> bool "Rockchip DesignWare PCIe controller"
> select PCIE_DW
> diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
> index 8ba7b67f5e50..bf5c311875a1 100644
> --- a/drivers/pci/controller/dwc/Makefile
> +++ b/drivers/pci/controller/dwc/Makefile
> @@ -3,6 +3,7 @@ obj-$(CONFIG_PCIE_DW) += pcie-designware.o
> obj-$(CONFIG_PCIE_DW_HOST) += pcie-designware-host.o
> obj-$(CONFIG_PCIE_DW_EP) += pcie-designware-ep.o
> obj-$(CONFIG_PCIE_DW_PLAT) += pcie-designware-plat.o
> +obj-$(CONFIG_PCIE_BT1) += pcie-bt1.o
> obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o
> obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
> obj-$(CONFIG_PCIE_FU740) += pcie-fu740.o
> diff --git a/drivers/pci/controller/dwc/pcie-bt1.c b/drivers/pci/controller/dwc/pcie-bt1.c
> new file mode 100644
> index 000000000000..3346770e6654
> --- /dev/null
> +++ b/drivers/pci/controller/dwc/pcie-bt1.c
> @@ -0,0 +1,643 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2021 BAIKAL ELECTRONICS, JSC
2022?
> + *
> + * Authors:
> + * Vadim Vlasov <Vadim.Vlasov@xxxxxxxxxxxxxxxxxxxx>
> + * Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> + *
> + * Baikal-T1 PCIe controller driver
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/types.h>
> +
> +#include "pcie-designware.h"
> +
> +/* Baikal-T1 System CCU control registers */
> +#define BT1_CCU_PCIE_CLKC 0x140
> +#define BT1_CCU_PCIE_REQ_PCS_CLK BIT(16)
> +#define BT1_CCU_PCIE_REQ_MAC_CLK BIT(17)
> +#define BT1_CCU_PCIE_REQ_PIPE_CLK BIT(18)
> +
> +#define BT1_CCU_PCIE_RSTC 0x144
> +#define BT1_CCU_PCIE_REQ_LINK_RST BIT(13)
> +#define BT1_CCU_PCIE_REQ_SMLH_RST BIT(14)
> +#define BT1_CCU_PCIE_REQ_PHY_RST BIT(16)
> +#define BT1_CCU_PCIE_REQ_CORE_RST BIT(24)
> +#define BT1_CCU_PCIE_REQ_STICKY_RST BIT(26)
> +#define BT1_CCU_PCIE_REQ_NSTICKY_RST BIT(27)
> +
> +#define BT1_CCU_PCIE_PMSC 0x148
> +#define BT1_CCU_PCIE_LTSSM_STATE_MASK GENMASK(5, 0)
> +#define BT1_CCU_PCIE_LTSSM_DET_QUIET 0x00
> +#define BT1_CCU_PCIE_LTSSM_DET_ACT 0x01
> +#define BT1_CCU_PCIE_LTSSM_POLL_ACT 0x02
> +#define BT1_CCU_PCIE_LTSSM_POLL_COMP 0x03
> +#define BT1_CCU_PCIE_LTSSM_POLL_CONF 0x04
> +#define BT1_CCU_PCIE_LTSSM_PRE_DET_QUIET 0x05
> +#define BT1_CCU_PCIE_LTSSM_DET_WAIT 0x06
> +#define BT1_CCU_PCIE_LTSSM_CFG_LNKWD_START 0x07
> +#define BT1_CCU_PCIE_LTSSM_CFG_LNKWD_ACEPT 0x08
> +#define BT1_CCU_PCIE_LTSSM_CFG_LNNUM_WAIT 0x09
> +#define BT1_CCU_PCIE_LTSSM_CFG_LNNUM_ACEPT 0x0a
> +#define BT1_CCU_PCIE_LTSSM_CFG_COMPLETE 0x0b
> +#define BT1_CCU_PCIE_LTSSM_CFG_IDLE 0x0c
> +#define BT1_CCU_PCIE_LTSSM_RCVR_LOCK 0x0d
> +#define BT1_CCU_PCIE_LTSSM_RCVR_SPEED 0x0e
> +#define BT1_CCU_PCIE_LTSSM_RCVR_RCVRCFG 0x0f
> +#define BT1_CCU_PCIE_LTSSM_RCVR_IDLE 0x10
> +#define BT1_CCU_PCIE_LTSSM_L0 0x11
> +#define BT1_CCU_PCIE_LTSSM_L0S 0x12
> +#define BT1_CCU_PCIE_LTSSM_L123_SEND_IDLE 0x13
> +#define BT1_CCU_PCIE_LTSSM_L1_IDLE 0x14
> +#define BT1_CCU_PCIE_LTSSM_L2_IDLE 0x15
> +#define BT1_CCU_PCIE_LTSSM_L2_WAKE 0x16
> +#define BT1_CCU_PCIE_LTSSM_DIS_ENTRY 0x17
> +#define BT1_CCU_PCIE_LTSSM_DIS_IDLE 0x18
> +#define BT1_CCU_PCIE_LTSSM_DISABLE 0x19
> +#define BT1_CCU_PCIE_LTSSM_LPBK_ENTRY 0x1a
> +#define BT1_CCU_PCIE_LTSSM_LPBK_ACTIVE 0x1b
> +#define BT1_CCU_PCIE_LTSSM_LPBK_EXIT 0x1c
> +#define BT1_CCU_PCIE_LTSSM_LPBK_EXIT_TOUT 0x1d
> +#define BT1_CCU_PCIE_LTSSM_HOT_RST_ENTRY 0x1e
> +#define BT1_CCU_PCIE_LTSSM_HOT_RST 0x1f
> +#define BT1_CCU_PCIE_LTSSM_RCVR_EQ0 0x20
> +#define BT1_CCU_PCIE_LTSSM_RCVR_EQ1 0x21
> +#define BT1_CCU_PCIE_LTSSM_RCVR_EQ2 0x22
> +#define BT1_CCU_PCIE_LTSSM_RCVR_EQ3 0x23
> +#define BT1_CCU_PCIE_SMLH_LINKUP BIT(6)
> +#define BT1_CCU_PCIE_RDLH_LINKUP BIT(7)
> +#define BT1_CCU_PCIE_PM_LINKSTATE_L0S BIT(8)
> +#define BT1_CCU_PCIE_PM_LINKSTATE_L1 BIT(9)
> +#define BT1_CCU_PCIE_PM_LINKSTATE_L2 BIT(10)
> +#define BT1_CCU_PCIE_L1_PENDING BIT(12)
> +#define BT1_CCU_PCIE_REQ_EXIT_L1 BIT(14)
> +#define BT1_CCU_PCIE_LTSSM_RCVR_EQ BIT(15)
> +#define BT1_CCU_PCIE_PM_DSTAT_MASK GENMASK(18, 16)
> +#define BT1_CCU_PCIE_PM_PME_EN BIT(20)
> +#define BT1_CCU_PCIE_PM_PME_STATUS BIT(21)
> +#define BT1_CCU_PCIE_AUX_PM_EN BIT(22)
> +#define BT1_CCU_PCIE_AUX_PWR_DET BIT(23)
> +#define BT1_CCU_PCIE_WAKE_DET BIT(24)
> +#define BT1_CCU_PCIE_TURNOFF_REQ BIT(30)
> +#define BT1_CCU_PCIE_TURNOFF_ACK BIT(31)
> +
> +#define BT1_CCU_PCIE_GENC 0x14c
> +#define BT1_CCU_PCIE_LTSSM_EN BIT(1)
> +#define BT1_CCU_PCIE_DBI2_MODE BIT(2)
> +#define BT1_CCU_PCIE_MGMT_EN BIT(3)
> +#define BT1_CCU_PCIE_RXLANE_FLIP_EN BIT(16)
> +#define BT1_CCU_PCIE_TXLANE_FLIP_EN BIT(17)
> +#define BT1_CCU_PCIE_SLV_XFER_PEND BIT(24)
> +#define BT1_CCU_PCIE_RCV_XFER_PEND BIT(25)
> +#define BT1_CCU_PCIE_DBI_XFER_PEND BIT(26)
> +#define BT1_CCU_PCIE_DMA_XFER_PEND BIT(27)
> +
> +#define BT1_CCU_PCIE_LTSSM_LINKUP(_pmsc) \
> +({ \
> + int __state = FIELD_GET(BT1_CCU_PCIE_LTSSM_STATE_MASK, _pmsc); \
> + __state >= BT1_CCU_PCIE_LTSSM_L0 && __state <= BT1_CCU_PCIE_LTSSM_L2_WAKE; \
> +})
> +
> +/* Baikal-T1 PCIe specific control registers */
> +#define BT1_PCIE_AXI2MGM_LANENUM 0xd04
> +#define BT1_PCIE_AXI2MGM_LANESEL_MASK GENMASK(3, 0)
> +
> +#define BT1_PCIE_AXI2MGM_ADDRCTL 0xd08
> +#define BT1_PCIE_AXI2MGM_PHYREG_ADDR_MASK GENMASK(20, 0)
> +#define BT1_PCIE_AXI2MGM_READ_FLAG BIT(29)
> +#define BT1_PCIE_AXI2MGM_DONE BIT(30)
> +#define BT1_PCIE_AXI2MGM_BUSY BIT(31)
> +
> +#define BT1_PCIE_AXI2MGM_WRITEDATA 0xd0c
> +#define BT1_PCIE_AXI2MGM_WDATA GENMASK(15, 0)
> +
> +#define BT1_PCIE_AXI2MGM_READDATA 0xd10
> +#define BT1_PCIE_AXI2MGM_RDATA GENMASK(15, 0)
> +
> +/* Generic Baikal-T1 PCIe interface resources */
> +#define BT1_PCIE_NUM_APP_CLKS ARRAY_SIZE(bt1_pcie_app_clks)
> +#define BT1_PCIE_NUM_CORE_CLKS ARRAY_SIZE(bt1_pcie_core_clks)
> +#define BT1_PCIE_NUM_APP_RSTS ARRAY_SIZE(bt1_pcie_app_rsts)
> +#define BT1_PCIE_NUM_CORE_RSTS ARRAY_SIZE(bt1_pcie_core_rsts)
> +
> +/* PCIe bus setup delays and timeouts */
> +#define BT1_PCIE_RST_DELAY_MS 100
> +#define BT1_PCIE_RUN_DELAY_US 100
> +#define BT1_PCIE_REQ_DELAY_US 1
> +#define BT1_PCIE_REQ_TIMEOUT_US 1000
> +#define BT1_PCIE_LNK_DELAY_US 1000
> +#define BT1_PCIE_LNK_TIMEOUT_US 1000000
> +
> +static const enum dw_pcie_app_clk bt1_pcie_app_clks[] = {
> + DW_PCIE_DBI_CLK, DW_PCIE_MSTR_CLK, DW_PCIE_SLV_CLK,
> +};
> +
> +static const enum dw_pcie_core_clk bt1_pcie_core_clks[] = {
> + DW_PCIE_REF_CLK,
> +};
> +
> +static const enum dw_pcie_app_rst bt1_pcie_app_rsts[] = {
> + DW_PCIE_MSTR_RST, DW_PCIE_SLV_RST,
> +};
> +
> +static const enum dw_pcie_core_rst bt1_pcie_core_rsts[] = {
> + DW_PCIE_NON_STICKY_RST, DW_PCIE_STICKY_RST, DW_PCIE_CORE_RST,
> + DW_PCIE_PIPE_RST, DW_PCIE_PHY_RST, DW_PCIE_HOT_RST, DW_PCIE_PWR_RST,
> +};
> +
> +struct bt1_pcie {
> + struct dw_pcie dw;
> + struct platform_device *pdev;
> + struct regmap *sys_regs;
> +};
> +#define to_bt1_pcie(_dw) container_of(_dw, struct bt1_pcie, dw)
> +
> +/*
> + * Baikal-T1 MMIO space must be read/written by the dword-aligned
> + * instructions. Note the methods are optimized to have the dword operations
> + * performed with minimum overhead as the most frequently used ones.
> + */
> +static int bt1_pcie_read_mmio(void __iomem *addr, int size, u32 *val)
> +{
> + unsigned int ofs = (uintptr_t)addr & 0x3;
> +
> + if (!IS_ALIGNED((uintptr_t)addr, size))
> + return -EINVAL;
> +
> + *val = readl(addr - ofs) >> ofs * BITS_PER_BYTE;
Why can't you use the _relaxed variants?
> + if (size == 4) {
> + return 0;
> + } else if (size == 2) {
> + *val &= 0xffff;
> + return 0;
> + } else if (size == 1) {
> + *val &= 0xff;
> + return 0;
> + }
> +
> + return -EINVAL;
> +}
> +
[...]
> +/*
> + * Implements the cold reset procedure in accordance with the reference manual
> + * and available PM signals.
> + */
> +static int bt1_pcie_cold_start_bus(struct bt1_pcie *btpci)
> +{
> + struct device *dev = btpci->dw.dev;
> + struct dw_pcie *pci = &btpci->dw;
> + u32 val;
> + int ret;
> +
> + /* First get out of the Power/Hot reset state */
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_PWR_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert PHY reset\n");
> + return ret;
> + }
> +
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_HOT_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert hot reset\n");
> + goto err_assert_pwr_rst;
> + }
> +
> + /* Wait for the PM-core to stop requesting the PHY reset */
What is PM core here? By first look I thought you are referring to Linux PM
core framework.
> + ret = regmap_read_poll_timeout(btpci->sys_regs, BT1_CCU_PCIE_RSTC, val,
> + !(val & BT1_CCU_PCIE_REQ_PHY_RST),
> + BT1_PCIE_REQ_DELAY_US, BT1_PCIE_REQ_TIMEOUT_US);
> + if (ret) {
> + dev_err(dev, "Timed out waiting for PM to stop PHY resetting\n");
With relation to my above comment, this log might be confusing.
> + goto err_assert_hot_rst;
> + }
> +
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_PHY_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert PHY reset\n");
> + goto err_assert_hot_rst;
> + }
> +
> + /* Clocks can be now enabled, but the ref one is crucial at this stage */
> + ret = clk_bulk_prepare_enable(DW_PCIE_NUM_APP_CLKS, pci->app_clks);
> + if (ret) {
> + dev_err(dev, "Failed to enable app clocks\n");
> + goto err_assert_phy_rst;
> + }
> +
> + ret = clk_bulk_prepare_enable(DW_PCIE_NUM_CORE_CLKS, pci->core_clks);
> + if (ret) {
> + dev_err(dev, "Failed to enable ref clocks\n");
> + goto err_disable_app_clk;
> + }
> +
> + /* Wait for the PM to stop requesting the controller core reset */
> + ret = regmap_read_poll_timeout(btpci->sys_regs, BT1_CCU_PCIE_RSTC, val,
> + !(val & BT1_CCU_PCIE_REQ_CORE_RST),
> + BT1_PCIE_REQ_DELAY_US, BT1_PCIE_REQ_TIMEOUT_US);
> + if (ret) {
> + dev_err(dev, "Timed out waiting for PM to stop core resetting\n");
> + goto err_disable_core_clk;
> + }
> +
> + /* PCS-PIPE interface and controller core can be now activated */
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_PIPE_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert PIPE reset\n");
> + goto err_disable_core_clk;
> + }
> +
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_CORE_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert core reset\n");
> + goto err_assert_pipe_rst;
> + }
> +
> + /* It's recommended to reset the core and application logic together */
> + ret = reset_control_bulk_reset(DW_PCIE_NUM_APP_RSTS, pci->app_rsts);
> + if (ret) {
> + dev_err(dev, "Failed to reset app domain\n");
> + goto err_assert_core_rst;
> + }
> +
> + /* Sticky/Non-sticky CSR flags can be now unreset too */
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_STICKY_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert sticky reset\n");
> + goto err_assert_core_rst;
> + }
> +
> + ret = reset_control_deassert(pci->core_rsts[DW_PCIE_NON_STICKY_RST].rstc);
> + if (ret) {
> + dev_err(dev, "Failed to deassert non-sticky reset\n");
> + goto err_assert_sticky_rst;
> + }
> +
> + /* Activate the PCIe bus peripheral devices */
> + gpiod_set_value_cansleep(pci->pe_rst, 0);
> +
> + /* Make sure the state is settled (LTSSM is still disabled though) */
> + usleep_range(BT1_PCIE_RUN_DELAY_US, BT1_PCIE_RUN_DELAY_US + 100);
> +
> + return 0;
> +
> +err_assert_sticky_rst:
> + reset_control_assert(pci->core_rsts[DW_PCIE_STICKY_RST].rstc);
> +
> +err_assert_core_rst:
> + reset_control_assert(pci->core_rsts[DW_PCIE_CORE_RST].rstc);
> +
> +err_assert_pipe_rst:
> + reset_control_assert(pci->core_rsts[DW_PCIE_PIPE_RST].rstc);
> +
> +err_disable_core_clk:
> + clk_bulk_disable_unprepare(DW_PCIE_NUM_CORE_CLKS, pci->core_clks);
> +
> +err_disable_app_clk:
> + clk_bulk_disable_unprepare(DW_PCIE_NUM_APP_CLKS, pci->app_clks);
> +
> +err_assert_phy_rst:
> + reset_control_assert(pci->core_rsts[DW_PCIE_PHY_RST].rstc);
> +
> +err_assert_hot_rst:
> + reset_control_assert(pci->core_rsts[DW_PCIE_HOT_RST].rstc);
> +
> +err_assert_pwr_rst:
> + reset_control_assert(pci->core_rsts[DW_PCIE_PWR_RST].rstc);
> +
> + return ret;
> +}
> +
> +static int bt1_pcie_host_init(struct dw_pcie_rp *pp)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> + struct bt1_pcie *btpci = to_bt1_pcie(pci);
> + int ret;
> +
> + ret = bt1_pcie_get_resources(btpci);
> + if (ret)
> + return ret;
> +
> + bt1_pcie_full_stop_bus(btpci, true);
> +
> + return bt1_pcie_cold_start_bus(btpci);
> +}
> +
> +static void bt1_pcie_host_deinit(struct dw_pcie_rp *pp)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
> + struct bt1_pcie *btpci = to_bt1_pcie(pci);
> +
> + bt1_pcie_full_stop_bus(btpci, false);
> +}
> +
> +static const struct dw_pcie_host_ops bt1_pcie_host_ops = {
> + .host_init = bt1_pcie_host_init,
> + .host_deinit = bt1_pcie_host_deinit,
> +};
> +
> +static struct bt1_pcie *bt1_pcie_create_data(struct platform_device *pdev)
> +{
Since this function is called only from probe, it is better to move it there
itself. It is common for drivers to allocate platform resource in the probe
itself.
> + struct bt1_pcie *btpci;
> +
> + btpci = devm_kzalloc(&pdev->dev, sizeof(*btpci), GFP_KERNEL);
> + if (!btpci)
> + return ERR_PTR(-ENOMEM);
> +
> + btpci->pdev = pdev;
> +
> + platform_set_drvdata(pdev, btpci);
> +
> + return btpci;
> +}
> +
> +static int bt1_pcie_add_port(struct bt1_pcie *btpci)
> +{
This also can be moved to probe.
> + struct device *dev = &btpci->pdev->dev;
> + int ret;
> +
> + btpci->dw.version = DW_PCIE_VER_460A;
> + btpci->dw.dev = dev;
> + btpci->dw.ops = &bt1_pcie_ops;
> +
> + btpci->dw.pp.num_vectors = MAX_MSI_IRQS;
> + btpci->dw.pp.ops = &bt1_pcie_host_ops;
> +
> + dw_pcie_cap_set(&btpci->dw, REQ_RES);
> +
> + ret = dw_pcie_host_init(&btpci->dw.pp);
> +
> + return dev_err_probe(dev, ret, "Failed to initialize DWC PCIe host\n");
> +}
> +
> +static void bt1_pcie_del_port(struct bt1_pcie *btpci)
> +{
> + dw_pcie_host_deinit(&btpci->dw.pp);
> +}
> +
> +static int bt1_pcie_probe(struct platform_device *pdev)
> +{
> + struct bt1_pcie *btpci;
> +
> + btpci = bt1_pcie_create_data(pdev);
> + if (IS_ERR(btpci))
> + return PTR_ERR(btpci);
> +
> + return bt1_pcie_add_port(btpci);
> +}
> +
> +static int bt1_pcie_remove(struct platform_device *pdev)
> +{
> + struct bt1_pcie *btpci = platform_get_drvdata(pdev);
> +
> + bt1_pcie_del_port(btpci);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id bt1_pcie_of_match[] = {
> + { .compatible = "baikal,bt1-pcie" },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, bt1_pcie_of_match);
> +
> +static struct platform_driver bt1_pcie_driver = {
> + .probe = bt1_pcie_probe,
> + .remove = bt1_pcie_remove,
> + .driver = {
> + .name = "bt1-pcie",
> + .of_match_table = bt1_pcie_of_match,
You might also want to add PROBE_ASYNCHRONOUS flag to allow parallel probing of
drivers while the dwc core waits for PHY link to be up in dw_pcie_wait_for_link().
Thanks,
Mani
> + },
> +};
> +module_platform_driver(bt1_pcie_driver);
> +
> +MODULE_AUTHOR("Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Baikal-T1 PCIe driver");
> +MODULE_LICENSE("GPL");
> --
> 2.38.1
>
>
--
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