[PATCH] pci: Fix configuring io/memory base and limit registers of PCI bridges

[Stefan Roese]

Added Bin to cc.

On 10.09.21 13:33, Pali Rohár wrote:
> Lower 4 bits of PCI_MEMORY_BASE and PCI_MEMORY_LIMIT registers are reserved
> and should be zero. So do not set them to non-zero value.
> 
> Lower 4 bits of PCI_PREF_MEMORY_BASE and PCI_PREF_MEMORY_LIMIT registers
> contain information if 64-bit memory addressing is supported. So preserve
> this information when overwriting these registers.
> 
> Lower 4 bits of PCI_IO_BASE and PCI_IO_LIMIT register contain information
> if 32-bit io addressing is supported. So preserve this information and do
> not try to configure 32-bit io addressing (via PCI_IO_BASE_UPPER16 and
> PCI_IO_LIMIT_UPPER16 registers) when it is unsupported.
> 
> Signed-off-by: Pali Rohár <pali at kernel.org>

Reviewed-by: Stefan Roese <sr at denx.de>

Thanks,
Stefan

> ---
>   drivers/pci/pci_auto.c | 39 +++++++++++++++++++++++++++++----------
>   1 file changed, 29 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c
> index b128a05dd380..7b6e629cae70 100644
> --- a/drivers/pci/pci_auto.c
> +++ b/drivers/pci/pci_auto.c
> @@ -165,6 +165,7 @@ void dm_pciauto_prescan_setup_bridge(struct udevice *dev, int sub_bus)
>   	struct pci_region *pci_prefetch;
>   	struct pci_region *pci_io;
>   	u16 cmdstat, prefechable_64;
> +	u8 io_32;
>   	struct udevice *ctlr = pci_get_controller(dev);
>   	struct pci_controller *ctlr_hose = dev_get_uclass_priv(ctlr);
>   
> @@ -175,6 +176,8 @@ void dm_pciauto_prescan_setup_bridge(struct udevice *dev, int sub_bus)
>   	dm_pci_read_config16(dev, PCI_COMMAND, &cmdstat);
>   	dm_pci_read_config16(dev, PCI_PREF_MEMORY_BASE, &prefechable_64);
>   	prefechable_64 &= PCI_PREF_RANGE_TYPE_MASK;
> +	dm_pci_read_config8(dev, PCI_IO_LIMIT, &io_32);
> +	io_32 &= PCI_IO_RANGE_TYPE_MASK;
>   
>   	/* Configure bus number registers */
>   	dm_pci_write_config8(dev, PCI_PRIMARY_BUS,
> @@ -191,7 +194,8 @@ void dm_pciauto_prescan_setup_bridge(struct udevice *dev, int sub_bus)
>   		 * I/O space
>   		 */
>   		dm_pci_write_config16(dev, PCI_MEMORY_BASE,
> -				      (pci_mem->bus_lower & 0xfff00000) >> 16);
> +				      ((pci_mem->bus_lower & 0xfff00000) >> 16) &
> +				      PCI_MEMORY_RANGE_MASK);
>   
>   		cmdstat |= PCI_COMMAND_MEMORY;
>   	}
> @@ -205,7 +209,8 @@ void dm_pciauto_prescan_setup_bridge(struct udevice *dev, int sub_bus)
>   		 * I/O space
>   		 */
>   		dm_pci_write_config16(dev, PCI_PREF_MEMORY_BASE,
> -				(pci_prefetch->bus_lower & 0xfff00000) >> 16);
> +				(((pci_prefetch->bus_lower & 0xfff00000) >> 16) &
> +				PCI_PREF_RANGE_MASK) | prefechable_64);
>   		if (prefechable_64 == PCI_PREF_RANGE_TYPE_64)
>   #ifdef CONFIG_SYS_PCI_64BIT
>   			dm_pci_write_config32(dev, PCI_PREF_BASE_UPPER32,
> @@ -217,8 +222,10 @@ void dm_pciauto_prescan_setup_bridge(struct udevice *dev, int sub_bus)
>   		cmdstat |= PCI_COMMAND_MEMORY;
>   	} else {
>   		/* We don't support prefetchable memory for now, so disable */
> -		dm_pci_write_config16(dev, PCI_PREF_MEMORY_BASE, 0x1000);
> -		dm_pci_write_config16(dev, PCI_PREF_MEMORY_LIMIT, 0x0);
> +		dm_pci_write_config16(dev, PCI_PREF_MEMORY_BASE, 0x1000 |
> +								prefechable_64);
> +		dm_pci_write_config16(dev, PCI_PREF_MEMORY_LIMIT, 0x0 |
> +								prefechable_64);
>   		if (prefechable_64 == PCI_PREF_RANGE_TYPE_64) {
>   			dm_pci_write_config16(dev, PCI_PREF_BASE_UPPER32, 0x0);
>   			dm_pci_write_config16(dev, PCI_PREF_LIMIT_UPPER32, 0x0);
> @@ -230,8 +237,10 @@ void dm_pciauto_prescan_setup_bridge(struct udevice *dev, int sub_bus)
>   		pciauto_region_align(pci_io, 0x1000);
>   
>   		dm_pci_write_config8(dev, PCI_IO_BASE,
> -				     (pci_io->bus_lower & 0x0000f000) >> 8);
> -		dm_pci_write_config16(dev, PCI_IO_BASE_UPPER16,
> +				     (((pci_io->bus_lower & 0x0000f000) >> 8) &
> +				     PCI_IO_RANGE_MASK) | io_32);
> +		if (io_32 == PCI_IO_RANGE_TYPE_32)
> +			dm_pci_write_config16(dev, PCI_IO_BASE_UPPER16,
>   				      (pci_io->bus_lower & 0xffff0000) >> 16);
>   
>   		cmdstat |= PCI_COMMAND_IO;
> @@ -261,7 +270,8 @@ void dm_pciauto_postscan_setup_bridge(struct udevice *dev, int sub_bus)
>   		pciauto_region_align(pci_mem, 0x100000);
>   
>   		dm_pci_write_config16(dev, PCI_MEMORY_LIMIT,
> -				      (pci_mem->bus_lower - 1) >> 16);
> +				      ((pci_mem->bus_lower - 1) >> 16) &
> +				      PCI_MEMORY_RANGE_MASK);
>   	}
>   
>   	if (pci_prefetch) {
> @@ -275,7 +285,8 @@ void dm_pciauto_postscan_setup_bridge(struct udevice *dev, int sub_bus)
>   		pciauto_region_align(pci_prefetch, 0x100000);
>   
>   		dm_pci_write_config16(dev, PCI_PREF_MEMORY_LIMIT,
> -				      (pci_prefetch->bus_lower - 1) >> 16);
> +				      (((pci_prefetch->bus_lower - 1) >> 16) &
> +				       PCI_PREF_RANGE_MASK) | prefechable_64);
>   		if (prefechable_64 == PCI_PREF_RANGE_TYPE_64)
>   #ifdef CONFIG_SYS_PCI_64BIT
>   			dm_pci_write_config32(dev, PCI_PREF_LIMIT_UPPER32,
> @@ -286,12 +297,20 @@ void dm_pciauto_postscan_setup_bridge(struct udevice *dev, int sub_bus)
>   	}
>   
>   	if (pci_io) {
> +		u8 io_32;
> +
> +		dm_pci_read_config8(dev, PCI_IO_LIMIT,
> +				     &io_32);
> +		io_32 &= PCI_IO_RANGE_TYPE_MASK;
> +
>   		/* Round I/O allocator to 4KB boundary */
>   		pciauto_region_align(pci_io, 0x1000);
>   
>   		dm_pci_write_config8(dev, PCI_IO_LIMIT,
> -				((pci_io->bus_lower - 1) & 0x0000f000) >> 8);
> -		dm_pci_write_config16(dev, PCI_IO_LIMIT_UPPER16,
> +				((((pci_io->bus_lower - 1) & 0x0000f000) >> 8) &
> +				PCI_IO_RANGE_MASK) | io_32);
> +		if (io_32 == PCI_IO_RANGE_TYPE_32)
> +			dm_pci_write_config16(dev, PCI_IO_LIMIT_UPPER16,
>   				((pci_io->bus_lower - 1) & 0xffff0000) >> 16);
>   	}
>   }
> 


Viele Grüße,
Stefan

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