[PATCH v2 09/10] pci: Add driver for Broadcom STB PCIe controller
Simon Glass
sjg at chromium.org
Wed May 6 16:47:16 CEST 2020
Hi Sylwester,
On Mon, 4 May 2020 at 06:45, Sylwester Nawrocki <s.nawrocki at samsung.com> wrote:
>
> This patch adds basic driver for the Broadcom STB PCIe host controller.
> The code is based on Linux upstream driver (pcie-brcmstb.c) with MSI
> handling removed. The inbound access memory region is not currently
> parsed from dma-ranges DT property and a fixed 4GB region is used.
>
> The patch has been tested on RPI4 board, i.e. on BCM2711 SoC with VL805
> USB Host Controller.
>
> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne at suse.de>
> Signed-off-by: Sylwester Nawrocki <s.nawrocki at samsung.com>
> ---
> Changes since v1:
> - fixed argument in brcm_pcie_set_ssc() function call
> - changed rc_bar2_size assignment to value 0xC0000000, as in upstream
> devicetre
> Changes since RFC:
> - reworked to align with current Linux mainline version and u-boot
> driver by Nicolas Saenz Julienne
>
> brcmstb pcie
> ---
> drivers/pci/Kconfig | 6 +
> drivers/pci/Makefile | 1 +
> drivers/pci/pcie_brcmstb.c | 594 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 601 insertions(+)
> create mode 100644 drivers/pci/pcie_brcmstb.c
A few small comments.
>
> diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> index 437cd9a..056a021 100644
> --- a/drivers/pci/Kconfig
> +++ b/drivers/pci/Kconfig
> @@ -197,4 +197,10 @@ config PCIE_MEDIATEK
> Say Y here if you want to enable Gen2 PCIe controller,
> which could be found on MT7623 SoC family.
>
> +config PCI_BRCMSTB
> + bool "Broadcom STB PCIe controller"
> + depends on DM_PCI
> + depends on ARCH_BCM283X
> + help
> + Say Y here if you want to enable Broadcom STB PCIe controller support.
What is STB? What features does this support? You should get a warning
here to write at least three lines.
> endif
> diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
> index c051ecc..3e53b1f 100644
> --- a/drivers/pci/Makefile
> +++ b/drivers/pci/Makefile
> @@ -43,3 +43,4 @@ obj-$(CONFIG_PCI_PHYTIUM) += pcie_phytium.o
> obj-$(CONFIG_PCIE_INTEL_FPGA) += pcie_intel_fpga.o
> obj-$(CONFIG_PCI_KEYSTONE) += pcie_dw_ti.o
> obj-$(CONFIG_PCIE_MEDIATEK) += pcie_mediatek.o
> +obj-$(CONFIG_PCI_BRCMSTB) += pcie_brcmstb.o
> diff --git a/drivers/pci/pcie_brcmstb.c b/drivers/pci/pcie_brcmstb.c
> new file mode 100644
> index 0000000..c6ddf92
> --- /dev/null
> +++ b/drivers/pci/pcie_brcmstb.c
> @@ -0,0 +1,594 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Broadcom STB PCIe controller driver
> + *
> + * Copyright (C) 2020 Samsung Electronics Co., Ltd.
> + *
> + * Based on upstream Linux kernel driver:
> + * drivers/pci/controller/pcie-brcmstb.c
> + * Copyright (C) 2009 - 2017 Broadcom
> + *
> + * Based driver by Nicolas Saenz Julienne
> + * Copyright (C) 2020 Nicolas Saenz Julienne <nsaenzjulienne at suse.de>
> + */
> +
> +#include <asm/io.h>
> +#include <common.h>
> +#include <dm.h>
> +#include <dm/ofnode.h>
> +#include <errno.h>
> +#include <linux/bitfield.h>
> +#include <linux/log2.h>
> +#include <pci.h>
Check ordering of include files:
https://www.denx.de/wiki/U-Boot/CodingStyle
> +
> +/* BRCM_PCIE_CAP_REGS - Offset for the mandatory capability config regs */
> +#define BRCM_PCIE_CAP_REGS 0x00ac
> +
> +/* Broadcom STB PCIe Register Offsets */
> +#define PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1 0x0188
> +#define PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK 0xc
> +#define PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN 0x0
> +
> +#define PCIE_RC_CFG_PRIV1_ID_VAL3 0x043c
> +#define PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK 0xffffff
> +
> +#define PCIE_RC_DL_MDIO_ADDR 0x1100
> +#define PCIE_RC_DL_MDIO_WR_DATA 0x1104
> +#define PCIE_RC_DL_MDIO_RD_DATA 0x1108
> +
> +#define PCIE_MISC_MISC_CTRL 0x4008
> +#define PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK 0x1000
> +#define PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK 0x2000
> +#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK 0x300000
> +#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128 0x0
> +#define PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK 0xf8000000
If you have a _MASK, don't you need a _SHIFT to allow you to read from
the field?
Can you drop the PCIE_MISC prefix? These are very long and local to this file.
> +
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LO 0x400c
> +#define PCIE_MEM_WIN0_LO(win) \
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LO + ((win) * 4)
> +
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_HI 0x4010
> +#define PCIE_MEM_WIN0_HI(win) \
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_HI + ((win) * 4)
> +
> +#define PCIE_MISC_RC_BAR1_CONFIG_LO 0x402c
> +#define PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK 0x1f
> +
> +#define PCIE_MISC_RC_BAR2_CONFIG_LO 0x4034
> +#define PCIE_MISC_RC_BAR2_CONFIG_LO_SIZE_MASK 0x1f
> +#define PCIE_MISC_RC_BAR2_CONFIG_HI 0x4038
> +
> +#define PCIE_MISC_RC_BAR3_CONFIG_LO 0x403c
> +#define PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK 0x1f
> +
> +#define PCIE_MISC_PCIE_STATUS 0x4068
> +#define PCIE_MISC_PCIE_STATUS_PCIE_PORT_MASK 0x80
> +#define PCIE_MISC_PCIE_STATUS_PCIE_DL_ACTIVE_MASK 0x20
> +#define PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK 0x10
> +#define PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK 0x40
> +
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT 0x4070
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK 0xfff00000
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK 0xfff0
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_HI_SHIFT 12
> +#define PCIE_MEM_WIN0_BASE_LIMIT(win) \
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT + ((win) * 4)
> +
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI 0x4080
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI_BASE_MASK 0xff
> +#define PCIE_MEM_WIN0_BASE_HI(win) \
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI + ((win) * 8)
> +
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI 0x4084
> +#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI_LIMIT_MASK 0xff
> +#define PCIE_MEM_WIN0_LIMIT_HI(win) \
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI + ((win) * 8)
> +
> +#define PCIE_MISC_HARD_PCIE_HARD_DEBUG 0x4204
> +#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK 0x2
> +#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK 0x08000000
> +
> +#define PCIE_MSI_INTR2_CLR 0x4508
> +#define PCIE_MSI_INTR2_MASK_SET 0x4510
> +
> +#define PCIE_EXT_CFG_DATA 0x8000
> +
> +#define PCIE_EXT_CFG_INDEX 0x9000
> +#define PCIE_EXT_BUSNUM_SHIFT 20
> +#define PCIE_EXT_SLOT_SHIFT 15
> +#define PCIE_EXT_FUNC_SHIFT 12
> +
> +#define PCIE_RGR1_SW_INIT_1 0x9210
> +#define PCIE_RGR1_SW_INIT_1_PERST_MASK 0x1
> +#define PCIE_RGR1_SW_INIT_1_INIT_MASK 0x2
> +
> +/* PCIe parameters */
> +#define BRCM_NUM_PCIE_OUT_WINS 0x4
> +
> +/* MDIO registers */
> +#define MDIO_PORT0 0x0
> +#define MDIO_DATA_MASK 0x7fffffff
> +#define MDIO_PORT_MASK 0xf0000
> +#define MDIO_REGAD_MASK 0xffff
> +#define MDIO_CMD_MASK 0xfff00000
> +#define MDIO_CMD_READ 0x1
> +#define MDIO_CMD_WRITE 0x0
> +#define MDIO_DATA_DONE_MASK 0x80000000
> +#define MDIO_RD_DONE(x) (((x) & MDIO_DATA_DONE_MASK) ? 1 : 0)
> +#define MDIO_WT_DONE(x) (((x) & MDIO_DATA_DONE_MASK) ? 0 : 1)
Are these two worth it? You can do this in your code:
if (readl(xxx) & MDIO_DATA_DONE_MASK)
If you must use these, then I think true/false are better than 1/0.
> +#define SSC_REGS_ADDR 0x1100
> +#define SET_ADDR_OFFSET 0x1f
> +#define SSC_CNTL_OFFSET 0x2
> +#define SSC_CNTL_OVRD_EN_MASK 0x8000
> +#define SSC_CNTL_OVRD_VAL_MASK 0x4000
> +#define SSC_STATUS_OFFSET 0x1
> +#define SSC_STATUS_SSC_MASK 0x400
> +#define SSC_STATUS_PLL_LOCK_MASK 0x800
> +
> +struct brcm_pcie {
struct comment
> + void __iomem *base;
> +
> + int gen;
> + bool ssc;
> +};
> +
> +#define msleep(a) udelay((a) * 1000)
This is already defined in U-Boot.
> +
> +/*
> + * This is to convert the size of the inbound "BAR" region to the
> + * non-linear values of PCIE_X_MISC_RC_BAR[123]_CONFIG_LO.SIZE
Please use a proper function comments with args and return value.
> + */
> +static int brcm_pcie_encode_ibar_size(u64 size)
> +{
> + int log2_in = ilog2(size);
> +
> + if (log2_in >= 12 && log2_in <= 15)
> + /* Covers 4KB to 32KB (inclusive) */
> + return (log2_in - 12) + 0x1c;
> + else if (log2_in >= 16 && log2_in <= 37)
> + /* Covers 64KB to 32GB, (inclusive) */
> + return log2_in - 15;
> + /* Something is awry so disable */
blank line always before return at end of function
> + return 0;
> +}
> +
> +/* Configuration space read/write support */
> +static inline int brcm_pcie_cfg_index(pci_dev_t bdf, int reg)
> +{
> + return (PCI_DEV(bdf) << PCIE_EXT_SLOT_SHIFT)
> + | (PCI_FUNC(bdf) << PCIE_EXT_FUNC_SHIFT)
> + | (PCI_BUS(bdf) << PCIE_EXT_BUSNUM_SHIFT)
> + | (reg & ~3);
> +}
> +
> +/* The controller is capable of serving in both RC and EP roles */
> +static bool brcm_pcie_rc_mode(struct brcm_pcie *pcie)
> +{
> + u32 val = readl(pcie->base + PCIE_MISC_PCIE_STATUS);
Consider using a struct for your registers which would reduce the size
of this code.
> +
> + return !!FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_PORT_MASK, val);
What is FIELD_GET? We have this sort of thing rejected in the past.
Here, since you return a bool, the !! should not be necessary.
> +}
> +
> +static bool brcm_pcie_link_up(struct brcm_pcie *pcie)
> +{
> + u32 val = readl(pcie->base + PCIE_MISC_PCIE_STATUS);
> + u32 dla = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_DL_ACTIVE_MASK, val);
> + u32 plu = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK, val);
PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK is way too long.
How about STATUS_PCIE_PHYLINKUP_MASK?
> +
> + return dla && plu;
> +}
> +
> +static int brcm_pcie_config_address(const struct udevice *udev, pci_dev_t bdf,
Please use 'dev' instead of udev for the device.
> + uint offset, void **paddress)
> +{
> + struct brcm_pcie *pcie = dev_get_priv(udev);
> + unsigned int bus = PCI_BUS(bdf);
> + unsigned int dev = PCI_DEV(bdf);
> + int idx;
> +
> + /*
> + * Busses 0 (host PCIe bridge) and 1 (its immediate child)
> + * are limited to a single device each
> + */
> + if ((bus == (udev->seq + 1)) && dev > 0)
> + return -ENODEV;
> +
> + /* Accesses to the RC go right to the RC registers if PCI device == 0 */
> + if (bus == udev->seq) {
> + if (PCI_DEV(bdf))
> + return -ENODEV;
You can't return that as there is a device. Perhaps ENXIO? Does this
indicate an internal error? If so you could add a comment here as to
how to fix it.
> +
> + *paddress = pcie->base + offset;
> + return 0;
> + }
> +
> + /* For devices, write to the config space index register */
> + idx = brcm_pcie_cfg_index(bdf, 0);
> +
> + writel(idx, pcie->base + PCIE_EXT_CFG_INDEX);
> + *paddress = pcie->base + PCIE_EXT_CFG_DATA + offset;
> +
> + return 0;
> +}
> +
> +static int brcm_pcie_read_config(const struct udevice *bus, pci_dev_t bdf,
> + uint offset, ulong *valuep,
> + enum pci_size_t size)
> +{
> + return pci_generic_mmap_read_config(bus, brcm_pcie_config_address,
> + bdf, offset, valuep, size);
> +}
> +
> +static int brcm_pcie_write_config(struct udevice *bus, pci_dev_t bdf,
> + uint offset, ulong value,
> + enum pci_size_t size)
> +{
> + return pci_generic_mmap_write_config(bus, brcm_pcie_config_address,
> + bdf, offset, value, size);
> +}
> +
> +static const char *link_speed_to_str(unsigned int s)
> +{
> + static const char * const speed_str[] = { "??", "2.5", "5.0", "8.0" };
> +
> + if (s >= ARRAY_SIZE(speed_str))
> + s = 0;
> +
> + return speed_str[s];
> +}
> +
> +static inline void brcm_pcie_bridge_sw_init_set(struct brcm_pcie *pcie, u32 val)
> +{
> + u32 tmp;
> +
> + tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1);
> + u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_INIT_MASK);
> + writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1);
See clrsetbits_le32(), etc. Below alos.
> +}
> +
> +static inline void brcm_pcie_perst_set(struct brcm_pcie *pcie, u32 val)
> +{
> + u32 tmp;
> +
> + tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1);
> + u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_PERST_MASK);
> + writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1);
> +}
> +
> +static u32 brcm_pcie_mdio_form_pkt(int port, int regad, int cmd)
> +{
> + u32 pkt = 0;
> +
> + pkt |= FIELD_PREP(MDIO_PORT_MASK, port);
> + pkt |= FIELD_PREP(MDIO_REGAD_MASK, regad);
> + pkt |= FIELD_PREP(MDIO_CMD_MASK, cmd);
> +
> + return pkt;
> +}
> +
> +/* Negative return value indicates error */
This would be incorporated in a full function comment
> +static int brcm_pcie_mdio_read(void __iomem *base, u8 port, u8 regad, u32 *val)
> +{
> + int tries;
> + u32 data;
> +
> + writel(brcm_pcie_mdio_form_pkt(port, regad, MDIO_CMD_READ),
> + base + PCIE_RC_DL_MDIO_ADDR);
> + readl(base + PCIE_RC_DL_MDIO_ADDR);
> +
> + data = readl(base + PCIE_RC_DL_MDIO_RD_DATA);
> + for (tries = 0; !MDIO_RD_DONE(data) && tries < 10; tries++) {
> + udelay(10);
> + data = readl(base + PCIE_RC_DL_MDIO_RD_DATA);
> + }
> +
> + *val = FIELD_GET(MDIO_DATA_MASK, data);
> + return MDIO_RD_DONE(data) ? 0 : -EIO;
> +}
> +
> +/* Negative return value indicates error */
> +static int brcm_pcie_mdio_write(void __iomem *base, u8 port,
> + u8 regad, u16 wrdata)
> +{
> + int tries;
> + u32 data;
> +
> + writel(brcm_pcie_mdio_form_pkt(port, regad, MDIO_CMD_WRITE),
> + base + PCIE_RC_DL_MDIO_ADDR);
> + readl(base + PCIE_RC_DL_MDIO_ADDR);
> + writel(MDIO_DATA_DONE_MASK | wrdata, base + PCIE_RC_DL_MDIO_WR_DATA);
> +
> + data = readl(base + PCIE_RC_DL_MDIO_WR_DATA);
> + for (tries = 0; !MDIO_WT_DONE(data) && tries < 10; tries++) {
> + udelay(10);
> + data = readl(base + PCIE_RC_DL_MDIO_WR_DATA);
> + }
> +
> + return MDIO_WT_DONE(data) ? 0 : -EIO;
> +}
> +
> +/*
> + * Configures device for Spread Spectrum Clocking (SSC) mode; negative
> + * return value indicates error.
> + */
> +static int brcm_pcie_set_ssc(struct brcm_pcie *pcie)
> +{
> + void __iomem *base = pcie->base;
> + int pll, ssc;
> + int ret;
> + u32 tmp;
> +
> + ret = brcm_pcie_mdio_write(base, MDIO_PORT0, SET_ADDR_OFFSET,
> + SSC_REGS_ADDR);
> + if (ret < 0)
> + return ret;
> +
> + ret = brcm_pcie_mdio_read(base, MDIO_PORT0, SSC_CNTL_OFFSET, &tmp);
> + if (ret < 0)
> + return ret;
> +
> + u32p_replace_bits(&tmp, 1, SSC_CNTL_OVRD_EN_MASK);
> + u32p_replace_bits(&tmp, 1, SSC_CNTL_OVRD_VAL_MASK);
> + ret = brcm_pcie_mdio_write(base, MDIO_PORT0, SSC_CNTL_OFFSET, tmp);
> + if (ret < 0)
> + return ret;
> +
> + udelay(1000);
> + ret = brcm_pcie_mdio_read(base, MDIO_PORT0, SSC_STATUS_OFFSET, &tmp);
> + if (ret < 0)
> + return ret;
> +
> + ssc = FIELD_GET(SSC_STATUS_SSC_MASK, tmp);
> + pll = FIELD_GET(SSC_STATUS_PLL_LOCK_MASK, tmp);
> +
> + return ssc && pll ? 0 : -EIO;
> +}
> +
> +/* Limits operation to a specific generation (1, 2, or 3) */
> +static void brcm_pcie_set_gen(struct brcm_pcie *pcie, int gen)
> +{
> + void __iomem *base = pcie->base;
> +
> + u16 lnkctl2 = readw(base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCTL2);
> + u32 lnkcap = readl(base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCAP);
> +
> + lnkcap = (lnkcap & ~PCI_EXP_LNKCAP_SLS) | gen;
> + writel(lnkcap, base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCAP);
> +
> + lnkctl2 = (lnkctl2 & ~0xf) | gen;
> + writew(lnkctl2, base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCTL2);
> +}
> +
> +static void brcm_pcie_set_outbound_win(struct brcm_pcie *pcie,
> + unsigned int win, u64 phys_addr,
> + u64 pcie_addr, u64 size)
> +{
> + void __iomem *base = pcie->base;
> + u32 phys_addr_mb_high, limit_addr_mb_high;
> + phys_addr_t phys_addr_mb, limit_addr_mb;
> + int high_addr_shift;
> + u32 tmp;
> +
> + /* Set the base of the pcie_addr window */
> + writel(lower_32_bits(pcie_addr), base + PCIE_MEM_WIN0_LO(win));
> + writel(upper_32_bits(pcie_addr), base + PCIE_MEM_WIN0_HI(win));
> +
> + /* Write the addr base & limit lower bits (in MBs) */
> + phys_addr_mb = phys_addr / SZ_1M;
> + limit_addr_mb = (phys_addr + size - 1) / SZ_1M;
> +
> + tmp = readl(base + PCIE_MEM_WIN0_BASE_LIMIT(win));
> + u32p_replace_bits(&tmp, phys_addr_mb,
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK);
> + u32p_replace_bits(&tmp, limit_addr_mb,
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK);
> + writel(tmp, base + PCIE_MEM_WIN0_BASE_LIMIT(win));
> +
> + /* Write the cpu & limit addr upper bits */
> + high_addr_shift = PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_HI_SHIFT;
> + phys_addr_mb_high = phys_addr_mb >> high_addr_shift;
> + tmp = readl(base + PCIE_MEM_WIN0_BASE_HI(win));
> + u32p_replace_bits(&tmp, phys_addr_mb_high,
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI_BASE_MASK);
> + writel(tmp, base + PCIE_MEM_WIN0_BASE_HI(win));
> +
> + limit_addr_mb_high = limit_addr_mb >> high_addr_shift;
> + tmp = readl(base + PCIE_MEM_WIN0_LIMIT_HI(win));
> + u32p_replace_bits(&tmp, limit_addr_mb_high,
> + PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI_LIMIT_MASK);
> + writel(tmp, base + PCIE_MEM_WIN0_LIMIT_HI(win));
> +}
> +
> +static int brcm_pcie_probe(struct udevice *dev)
> +{
> + struct udevice *ctlr = pci_get_controller(dev);
> + struct pci_controller *hose = dev_get_uclass_priv(ctlr);
> + struct brcm_pcie *pcie = dev_get_priv(dev);
> + void __iomem *base = pcie->base;
> + bool ssc_good = false;
> + int num_out_wins = 0;
> + u64 rc_bar2_offset, rc_bar2_size;
> + unsigned int scb_size_val;
> + int i, ret;
> + u16 nlw, cls, lnksta;
> + u32 tmp;
> +
> + /* Reset the bridge */
> + brcm_pcie_bridge_sw_init_set(pcie, 1);
> +
> + udelay(150);
Please add a comment as to how you chose the value, and below.
> +
> + /* Take the bridge out of reset */
> + brcm_pcie_bridge_sw_init_set(pcie, 0);
> +
> + tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
> + tmp &= ~PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK;
> + writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
> + /* Wait for SerDes to be stable */
> + udelay(150);
> +
> + /* Set SCB_MAX_BURST_SIZE, CFG_READ_UR_MODE, SCB_ACCESS_EN */
> + u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK);
> + u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK);
> + u32p_replace_bits(&tmp, PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128,
> + PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK);
> + writel(tmp, base + PCIE_MISC_MISC_CTRL);
> +
> + /*
> + * TODO: When support for other SoCs than BCM2711 is added we may
> + * need to use the base address and size(s) provided in the dma-ranges
> + * property.
> + */
> + rc_bar2_offset = 0;
> + rc_bar2_size = 0xc0000000;
> +
> + tmp = lower_32_bits(rc_bar2_offset);
> + u32p_replace_bits(&tmp, brcm_pcie_encode_ibar_size(rc_bar2_size),
> + PCIE_MISC_RC_BAR2_CONFIG_LO_SIZE_MASK);
> + writel(tmp, base + PCIE_MISC_RC_BAR2_CONFIG_LO);
> + writel(upper_32_bits(rc_bar2_offset),
> + base + PCIE_MISC_RC_BAR2_CONFIG_HI);
> +
> + scb_size_val = rc_bar2_size ?
> + ilog2(rc_bar2_size) - 15 : 0xf; /* 0xf is 1GB */
> + tmp = readl(base + PCIE_MISC_MISC_CTRL);
> + u32p_replace_bits(&tmp, scb_size_val,
> + PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK);
> + writel(tmp, base + PCIE_MISC_MISC_CTRL);
> +
> + /* Disable the PCIe->GISB memory window (RC_BAR1) */
> + tmp = readl(base + PCIE_MISC_RC_BAR1_CONFIG_LO);
> + tmp &= ~PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK;
> + writel(tmp, base + PCIE_MISC_RC_BAR1_CONFIG_LO);
> +
> + /* Disable the PCIe->SCB memory window (RC_BAR3) */
> + tmp = readl(base + PCIE_MISC_RC_BAR3_CONFIG_LO);
> + tmp &= ~PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK;
> + writel(tmp, base + PCIE_MISC_RC_BAR3_CONFIG_LO);
> +
> + /* Mask all interrupts since we are not handling any yet */
> + writel(0xffffffff, base + PCIE_MSI_INTR2_MASK_SET);
> +
> + /* Clear any interrupts we find on boot */
> + writel(0xffffffff, base + PCIE_MSI_INTR2_CLR);
> +
> + if (pcie->gen)
> + brcm_pcie_set_gen(pcie, pcie->gen);
> +
> + /* Unassert the fundamental reset */
> + brcm_pcie_perst_set(pcie, 0);
> +
> + /* Give the RC/EP time to wake up, before trying to configure RC.
> + * Intermittently check status for link-up, up to a total of 100ms.
> + */
> + for (i = 0; i < 100 && !brcm_pcie_link_up(pcie); i += 5)
> + msleep(5);
> +
> + if (!brcm_pcie_link_up(pcie)) {
> + printf("PCIe BRCM: link down\n");
> + return -ENODEV;
Again, cannot return that error
> + }
> +
> + if (!brcm_pcie_rc_mode(pcie)) {
> + printf("PCIe misconfigured; is in EP mode\n");
> + return -EINVAL;
> + }
> +
> + for (i = 0; i < hose->region_count; i++) {
> + struct pci_region *reg = &hose->regions[i];
> +
> + if (reg->flags != PCI_REGION_MEM)
> + continue;
> +
> + if (num_out_wins >= BRCM_NUM_PCIE_OUT_WINS)
> + return -EINVAL;
> +
> + brcm_pcie_set_outbound_win(pcie, num_out_wins, reg->phys_start,
> + reg->bus_start, reg->size);
> +
> + num_out_wins++;
> + }
> +
> + /*
> + * For config space accesses on the RC, show the right class for
> + * a PCIe-PCIe bridge (the default setting is to be EP mode).
> + */
> + tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
> + u32p_replace_bits(&tmp, 0x060400,
> + PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
> + writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
> +
> + if (pcie->ssc) {
> + ret = brcm_pcie_set_ssc(pcie);
> + if (ret == 0)
> + ssc_good = true;
> + else
> + printf("PCIe BRCM: failed attempt to enter SSC mode\n");
Should this return an error?
> + }
> +
> + lnksta = readw(base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKSTA);
> + cls = FIELD_GET(PCI_EXP_LNKSTA_CLS, lnksta);
> + nlw = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta);
> +
> + printf("PCIe BRCM: link up, %s Gbps x%u %s\n", link_speed_to_str(cls),
> + nlw, ssc_good ? "(SSC)" : "(!SSC)");
> +
> + /* PCIe->SCB endian mode for BAR */
> + tmp = readl(base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1);
> + u32p_replace_bits(&tmp, PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN,
> + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK);
> + writel(tmp, base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1);
> +
> + /*
> + * Refclk from RC should be gated with CLKREQ# input when ASPM L0s,L1
> + * is enabled => setting the CLKREQ_DEBUG_ENABLE field to 1.
> + */
> + tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
> + tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK;
> + writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
> +
> + return 0;
> +}
> +
> +static int brcm_pcie_ofdata_to_platdata(struct udevice *dev)
> +{
> + struct brcm_pcie *pcie = dev_get_priv(dev);
> + ofnode dn = dev_ofnode(dev);
> + u32 max_link_speed;
> + int ret;
> +
> + /* Get the controller base address */
> + pcie->base = dev_read_addr_ptr(dev);
> + if (!pcie->base)
> + return -EINVAL;
> +
> + pcie->ssc = ofnode_read_bool(dn, "brcm,enable-ssc");
> +
> + ret = ofnode_read_u32(dn, "max-link-speed", &max_link_speed);
> + if (ret < 0 || max_link_speed > 4)
> + pcie->gen = 0;
> + else
> + pcie->gen = max_link_speed;
> +
> + return 0;
> +}
> +
> +static const struct dm_pci_ops brcm_pcie_ops = {
> + .read_config = brcm_pcie_read_config,
> + .write_config = brcm_pcie_write_config,
> +};
> +
> +static const struct udevice_id brcm_pcie_ids[] = {
> + { .compatible = "brcm,bcm2711-pcie" },
> + { }
> +};
> +
> +U_BOOT_DRIVER(pcie_brcm_base) = {
> + .name = "pcie_brcm",
> + .id = UCLASS_PCI,
> + .ops = &brcm_pcie_ops,
> + .of_match = brcm_pcie_ids,
> + .probe = brcm_pcie_probe,
> + .ofdata_to_platdata = brcm_pcie_ofdata_to_platdata,
> + .priv_auto_alloc_size = sizeof(struct brcm_pcie),
> +};
> --
> 2.7.4
>
Regards,
Simon
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