Re: [PATCH v6 07/19] PCI: plda: Move the setup functions to pcie-plda-host.c

From: Emil Renner Berthing
Date: Sun Sep 17 2023 - 18:47:58 EST


Minda Chen wrote:
> Move setup functions to common pcie-plda-host.c.
>
> Signed-off-by: Minda Chen <minda.chen@xxxxxxxxxxxxxxxx>
> Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> ---
> drivers/pci/controller/plda/Kconfig | 4 +
> drivers/pci/controller/plda/Makefile | 1 +
> .../pci/controller/plda/pcie-microchip-host.c | 59 -------------
> drivers/pci/controller/plda/pcie-plda-host.c | 82 +++++++++++++++++++
> drivers/pci/controller/plda/pcie-plda.h | 6 ++
> 5 files changed, 93 insertions(+), 59 deletions(-)
> create mode 100644 drivers/pci/controller/plda/pcie-plda-host.c
>
> diff --git a/drivers/pci/controller/plda/Kconfig b/drivers/pci/controller/plda/Kconfig
> index 5cb3be4fc98c..e54a82ee94f5 100644
> --- a/drivers/pci/controller/plda/Kconfig
> +++ b/drivers/pci/controller/plda/Kconfig
> @@ -3,10 +3,14 @@
> menu "PLDA-based PCIe controllers"
> depends on PCI
>
> +config PCIE_PLDA_HOST
> + bool
> +
> config PCIE_MICROCHIP_HOST
> tristate "Microchip AXI PCIe controller"
> depends on PCI_MSI && OF
> select PCI_HOST_COMMON
> + select PCIE_PLDA_HOST
> help
> Say Y here if you want kernel to support the Microchip AXI PCIe
> Host Bridge driver.
> diff --git a/drivers/pci/controller/plda/Makefile b/drivers/pci/controller/plda/Makefile
> index e1a265cbf91c..4340ab007f44 100644
> --- a/drivers/pci/controller/plda/Makefile
> +++ b/drivers/pci/controller/plda/Makefile
> @@ -1,2 +1,3 @@
> # SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_PCIE_PLDA_HOST) += pcie-plda-host.o
> obj-$(CONFIG_PCIE_MICROCHIP_HOST) += pcie-microchip-host.o
> diff --git a/drivers/pci/controller/plda/pcie-microchip-host.c b/drivers/pci/controller/plda/pcie-microchip-host.c
> index 1d253acd6bc2..ac7126b0bacf 100644
> --- a/drivers/pci/controller/plda/pcie-microchip-host.c
> +++ b/drivers/pci/controller/plda/pcie-microchip-host.c
> @@ -837,65 +837,6 @@ static int mc_pcie_init_irq_domains(struct plda_pcie_rp *port)
> return mc_allocate_msi_domains(port);
> }
>
> -static void plda_pcie_setup_window(void __iomem *bridge_base_addr, u32 index,
> - phys_addr_t axi_addr, phys_addr_t pci_addr,
> - size_t size)
> -{
> - u32 atr_sz = ilog2(size) - 1;
> - u32 val;
> -
> - if (index == 0)
> - val = PCIE_CONFIG_INTERFACE;
> - else
> - val = PCIE_TX_RX_INTERFACE;
> -
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> - ATR0_AXI4_SLV0_TRSL_PARAM);
> -
> - val = lower_32_bits(axi_addr) | (atr_sz << ATR_SIZE_SHIFT) |
> - ATR_IMPL_ENABLE;
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> - ATR0_AXI4_SLV0_SRCADDR_PARAM);
> -
> - val = upper_32_bits(axi_addr);
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> - ATR0_AXI4_SLV0_SRC_ADDR);
> -
> - val = lower_32_bits(pci_addr);
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> - ATR0_AXI4_SLV0_TRSL_ADDR_LSB);
> -
> - val = upper_32_bits(pci_addr);
> - writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> - ATR0_AXI4_SLV0_TRSL_ADDR_UDW);
> -
> - val = readl(bridge_base_addr + ATR0_PCIE_WIN0_SRCADDR_PARAM);
> - val |= (ATR0_PCIE_ATR_SIZE << ATR0_PCIE_ATR_SIZE_SHIFT);
> - writel(val, bridge_base_addr + ATR0_PCIE_WIN0_SRCADDR_PARAM);
> - writel(0, bridge_base_addr + ATR0_PCIE_WIN0_SRC_ADDR);
> -}
> -
> -static int plda_pcie_setup_iomems(struct pci_host_bridge *bridge,
> - struct plda_pcie_rp *port)
> -{
> - void __iomem *bridge_base_addr = port->bridge_addr;
> - struct resource_entry *entry;
> - u64 pci_addr;
> - u32 index = 1;
> -
> - resource_list_for_each_entry(entry, &bridge->windows) {
> - if (resource_type(entry->res) == IORESOURCE_MEM) {
> - pci_addr = entry->res->start - entry->offset;
> - plda_pcie_setup_window(bridge_base_addr, index,
> - entry->res->start, pci_addr,
> - resource_size(entry->res));
> - index++;
> - }
> - }
> -
> - return 0;
> -}
> -
> static inline void mc_clear_secs(struct mc_pcie *port)
> {
> void __iomem *ctrl_base_addr = port->axi_base_addr + MC_PCIE_CTRL_ADDR;
> diff --git a/drivers/pci/controller/plda/pcie-plda-host.c b/drivers/pci/controller/plda/pcie-plda-host.c
> new file mode 100644
> index 000000000000..f0c7636f1f64
> --- /dev/null
> +++ b/drivers/pci/controller/plda/pcie-plda-host.c
> @@ -0,0 +1,82 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * PLDA PCIe XpressRich host controller driver
> + *
> + * Copyright (C) 2023 Microchip Co. Ltd
> + * StarFive Co. Ltd.
> + *
> + * Author: Daire McNamara <daire.mcnamara@xxxxxxxxxxxxx>
> + * Author: Minda Chen <minda.chen@xxxxxxxxxxxxxxxx>
> + */
> +
> +#include <linux/irqchip/chained_irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/msi.h>
> +#include <linux/of_address.h>
> +#include <linux/of_pci.h>
> +#include <linux/pci_regs.h>
> +#include <linux/pci-ecam.h>
> +#include <linux/platform_device.h>
> +
> +#include "pcie-plda.h"
> +
> +void plda_pcie_setup_window(void __iomem *bridge_base_addr, u32 index,
> + phys_addr_t axi_addr, phys_addr_t pci_addr,
> + size_t size)
> +{
> + u32 atr_sz = ilog2(size) - 1;
> + u32 val;
> +
> + if (index == 0)
> + val = PCIE_CONFIG_INTERFACE;
> + else
> + val = PCIE_TX_RX_INTERFACE;
> +
> + writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + ATR0_AXI4_SLV0_TRSL_PARAM);
> +
> + val = lower_32_bits(axi_addr) | (atr_sz << ATR_SIZE_SHIFT) |
> + ATR_IMPL_ENABLE;
> + writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + ATR0_AXI4_SLV0_SRCADDR_PARAM);
> +
> + val = upper_32_bits(axi_addr);
> + writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + ATR0_AXI4_SLV0_SRC_ADDR);
> +
> + val = lower_32_bits(pci_addr);
> + writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + ATR0_AXI4_SLV0_TRSL_ADDR_LSB);
> +
> + val = upper_32_bits(pci_addr);
> + writel(val, bridge_base_addr + (index * ATR_ENTRY_SIZE) +
> + ATR0_AXI4_SLV0_TRSL_ADDR_UDW);
> +
> + val = readl(bridge_base_addr + ATR0_PCIE_WIN0_SRCADDR_PARAM);
> + val |= (ATR0_PCIE_ATR_SIZE << ATR0_PCIE_ATR_SIZE_SHIFT);

I know this code is just a straight copy, but for future cleanups are we
guaranteed that this field is always zero?

Otherwise it looks a little suspicious to do read-modify-write, but just
set the (0x25 << 1) bits without clearing the field first.

> + writel(val, bridge_base_addr + ATR0_PCIE_WIN0_SRCADDR_PARAM);
> + writel(0, bridge_base_addr + ATR0_PCIE_WIN0_SRC_ADDR);
> +}
> +EXPORT_SYMBOL_GPL(plda_pcie_setup_window);
> +
> +int plda_pcie_setup_iomems(struct pci_host_bridge *bridge,
> + struct plda_pcie_rp *port)
> +{
> + void __iomem *bridge_base_addr = port->bridge_addr;
> + struct resource_entry *entry;
> + u64 pci_addr;
> + u32 index = 1;
> +
> + resource_list_for_each_entry(entry, &bridge->windows) {
> + if (resource_type(entry->res) == IORESOURCE_MEM) {
> + pci_addr = entry->res->start - entry->offset;
> + plda_pcie_setup_window(bridge_base_addr, index,
> + entry->res->start, pci_addr,
> + resource_size(entry->res));
> + index++;
> + }
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(plda_pcie_setup_iomems);
> diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
> index d04a571404b9..3deefd35fa5a 100644
> --- a/drivers/pci/controller/plda/pcie-plda.h
> +++ b/drivers/pci/controller/plda/pcie-plda.h
> @@ -119,4 +119,10 @@ struct plda_pcie_rp {
> struct plda_msi msi;
> void __iomem *bridge_addr;
> };
> +
> +void plda_pcie_setup_window(void __iomem *bridge_base_addr, u32 index,
> + phys_addr_t axi_addr, phys_addr_t pci_addr,
> + size_t size);
> +int plda_pcie_setup_iomems(struct pci_host_bridge *bridge,
> + struct plda_pcie_rp *port);
> #endif
> --
> 2.17.1