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

Minda Chen
2023-09-22T10:43:03Z

On 2023/9/18 6:45, Emil Renner Berthing wrote:
> Minda Chen wrote:
>> Move setup functions to common pcie-plda-host.c.
>>
>> Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
>> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
>> ---
>> 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@microchip.com>
>> + * Author: Minda Chen <minda.chen@starfivetech.com>
>> + */
>> +
>> +#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.
>
The reset value is zero. And this is called once.
Maybe I can add a patch to fix this.
>> + 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