[PATCH] riscv: enable multi-range memory layout

In order to enable PCIe passthrough on qemu riscv, the physical memory range between 3GB and 4GB is reserved. Therefore if guest has 4GB ram, two ranges are created as [2G, 3G) and [4G, 7G), currently u-boot sets ram_top to 4G - 1 if the gd->ram_top is above 4G in board_get_usable_ram_top(), but that address is not backed by ram. This patch selects the lowest range instead.
Signed-off-by: Fei Wu fei2.wu@intel.com --- arch/riscv/cpu/generic/dram.c | 2 +- configs/qemu-riscv64_smode_defconfig | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/cpu/generic/dram.c b/arch/riscv/cpu/generic/dram.c index 44e11bd56c..fb53a57b4e 100644 --- a/arch/riscv/cpu/generic/dram.c +++ b/arch/riscv/cpu/generic/dram.c @@ -13,7 +13,7 @@ DECLARE_GLOBAL_DATA_PTR;
int dram_init(void) { - return fdtdec_setup_mem_size_base(); + return fdtdec_setup_mem_size_base_lowest(); }
int dram_init_banksize(void) diff --git a/configs/qemu-riscv64_smode_defconfig b/configs/qemu-riscv64_smode_defconfig index 1d0f021ade..de08a49dab 100644 --- a/configs/qemu-riscv64_smode_defconfig +++ b/configs/qemu-riscv64_smode_defconfig @@ -1,6 +1,6 @@ CONFIG_RISCV=y CONFIG_SYS_MALLOC_LEN=0x800000 -CONFIG_NR_DRAM_BANKS=1 +CONFIG_NR_DRAM_BANKS=2 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x80200000 CONFIG_ENV_SIZE=0x20000

On 9/5/2023 6:09 PM, Fei Wu wrote:
In order to enable PCIe passthrough on qemu riscv, the physical memory range between 3GB and 4GB is reserved. Therefore if guest has 4GB ram, two ranges are created as [2G, 3G) and [4G, 7G), currently u-boot sets ram_top to 4G - 1 if the gd->ram_top is above 4G in board_get_usable_ram_top(), but that address is not backed by ram. This patch selects the lowest range instead.
I think multi-range memory layout is a common requirement, PCIe passthrough happens to be the first one to require it. Could anyone please take a look at this patch and give your comments?
Thanks, Fei.
Signed-off-by: Fei Wu fei2.wu@intel.com
arch/riscv/cpu/generic/dram.c | 2 +- configs/qemu-riscv64_smode_defconfig | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/cpu/generic/dram.c b/arch/riscv/cpu/generic/dram.c index 44e11bd56c..fb53a57b4e 100644 --- a/arch/riscv/cpu/generic/dram.c +++ b/arch/riscv/cpu/generic/dram.c @@ -13,7 +13,7 @@ DECLARE_GLOBAL_DATA_PTR;
int dram_init(void) {
- return fdtdec_setup_mem_size_base();
- return fdtdec_setup_mem_size_base_lowest();
}
int dram_init_banksize(void) diff --git a/configs/qemu-riscv64_smode_defconfig b/configs/qemu-riscv64_smode_defconfig index 1d0f021ade..de08a49dab 100644 --- a/configs/qemu-riscv64_smode_defconfig +++ b/configs/qemu-riscv64_smode_defconfig @@ -1,6 +1,6 @@ CONFIG_RISCV=y CONFIG_SYS_MALLOC_LEN=0x800000 -CONFIG_NR_DRAM_BANKS=1 +CONFIG_NR_DRAM_BANKS=2 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x80200000 CONFIG_ENV_SIZE=0x20000

Am 13. September 2023 04:23:14 MESZ schrieb "Wu, Fei" fei2.wu@intel.com:
On 9/5/2023 6:09 PM, Fei Wu wrote:
In order to enable PCIe passthrough on qemu riscv, the physical memory range between 3GB and 4GB is reserved. Therefore if guest has 4GB ram, two ranges are created as [2G, 3G) and [4G, 7G), currently u-boot sets ram_top to 4G - 1 if the gd->ram_top is above 4G in board_get_usable_ram_top(), but that address is not backed by ram. This patch selects the lowest range instead.
I think multi-range memory layout is a common requirement, PCIe passthrough happens to be the first one to require it. Could anyone please take a look at this patch and give your comments?
Thanks, Fei.
Signed-off-by: Fei Wu fei2.wu@intel.com
arch/riscv/cpu/generic/dram.c | 2 +- configs/qemu-riscv64_smode_defconfig | 2 +-
We should consider all riscv64 defconfigs.
Best regards
Heinrich
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/cpu/generic/dram.c b/arch/riscv/cpu/generic/dram.c index 44e11bd56c..fb53a57b4e 100644 --- a/arch/riscv/cpu/generic/dram.c +++ b/arch/riscv/cpu/generic/dram.c @@ -13,7 +13,7 @@ DECLARE_GLOBAL_DATA_PTR;
int dram_init(void) {
- return fdtdec_setup_mem_size_base();
- return fdtdec_setup_mem_size_base_lowest();
}
int dram_init_banksize(void) diff --git a/configs/qemu-riscv64_smode_defconfig b/configs/qemu-riscv64_smode_defconfig index 1d0f021ade..de08a49dab 100644 --- a/configs/qemu-riscv64_smode_defconfig +++ b/configs/qemu-riscv64_smode_defconfig @@ -1,6 +1,6 @@ CONFIG_RISCV=y CONFIG_SYS_MALLOC_LEN=0x800000 -CONFIG_NR_DRAM_BANKS=1 +CONFIG_NR_DRAM_BANKS=2 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x80200000 CONFIG_ENV_SIZE=0x20000

On 9/13/2023 1:05 PM, Heinrich Schuchardt wrote:
Am 13. September 2023 04:23:14 MESZ schrieb "Wu, Fei" fei2.wu@intel.com:
On 9/5/2023 6:09 PM, Fei Wu wrote:
In order to enable PCIe passthrough on qemu riscv, the physical memory range between 3GB and 4GB is reserved. Therefore if guest has 4GB ram, two ranges are created as [2G, 3G) and [4G, 7G), currently u-boot sets ram_top to 4G - 1 if the gd->ram_top is above 4G in board_get_usable_ram_top(), but that address is not backed by ram. This patch selects the lowest range instead.
I think multi-range memory layout is a common requirement, PCIe passthrough happens to be the first one to require it. Could anyone please take a look at this patch and give your comments?
Thanks, Fei.
Signed-off-by: Fei Wu fei2.wu@intel.com
arch/riscv/cpu/generic/dram.c | 2 +- configs/qemu-riscv64_smode_defconfig | 2 +-
We should consider all riscv64 defconfigs.
OK. I will update qemu-riscv64_defconfig, qemu-riscv64_smode_defconfig and qemu-riscv64_spl_defconfig.
Thanks, Fei.
Best regards
Heinrich
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/cpu/generic/dram.c b/arch/riscv/cpu/generic/dram.c index 44e11bd56c..fb53a57b4e 100644 --- a/arch/riscv/cpu/generic/dram.c +++ b/arch/riscv/cpu/generic/dram.c @@ -13,7 +13,7 @@ DECLARE_GLOBAL_DATA_PTR;
int dram_init(void) {
- return fdtdec_setup_mem_size_base();
- return fdtdec_setup_mem_size_base_lowest();
}
int dram_init_banksize(void) diff --git a/configs/qemu-riscv64_smode_defconfig b/configs/qemu-riscv64_smode_defconfig index 1d0f021ade..de08a49dab 100644 --- a/configs/qemu-riscv64_smode_defconfig +++ b/configs/qemu-riscv64_smode_defconfig @@ -1,6 +1,6 @@ CONFIG_RISCV=y CONFIG_SYS_MALLOC_LEN=0x800000 -CONFIG_NR_DRAM_BANKS=1 +CONFIG_NR_DRAM_BANKS=2 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x80200000 CONFIG_ENV_SIZE=0x20000
participants (3)
-
Fei Wu
-
Heinrich Schuchardt
-
Wu, Fei