Commit Graph

9 Commits

Author SHA1 Message Date
Sean Anderson
c33efafaf9 riscv: Rework riscv timer driver to only support S-mode
The riscv-timer driver currently serves as a shim for several riscv timer
drivers. This is not too desirable because it bypasses the usual timer
selection via the driver model. There is no easy way to specify an
alternate timing driver, or have the tick rate depend on the cpu's
configured frequency. The timer drivers also do not have device structs,
and so have to rely on storing parameters in gd_t. Lastly, there is no
initialization call, so driver init is done in the same function which
reads the time. This can result in confusing error messages. To a user, it
looks like the driver failed when trying to read the time, whereas it may
have failed while initializing.

This patch removes the shim functionality from the riscv-timer driver, and
has it instead implement the former rdtime.c timer driver. This is because
existing u-boot users who pass in a device tree (e.g. qemu) do not create a
timer device for S-mode u-boot. The existing behavior of creating the
riscv-timer device in the riscv cpu driver must be kept. The actual reading
of the CSRs has been redone in the style of Linux's get_cycles64.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2020-09-30 08:54:45 +08:00
Simon Glass
90526e9fba common: Drop net.h from common header
Move this header out of the common header. Network support is used in
quite a few places but it still does not warrant blanket inclusion.

Note that this net.h header itself has quite a lot in it. It could be
split into the driver-mode support, functions, structures, checksumming,
etc.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 17:33:31 -04:00
Bin Meng
ed1475e2f4 riscv: qemu: Remove the simple-bus driver for the SoC node
Prior to QEMU v3.1.0, QEMU generated the 'virt' SoC node with a
"riscv-virtio-soc" compatible string, and a "simple-bus" driver
was created to accommodate that special case in U-Boot.

Starting from QEMU v3.1.0, the SoC node was set as a "simple-bus",
hence the special simple-bus driver is no longer needed.

Update the doc to mention the latest tested QEMU version 4.2.0.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
2020-04-23 10:14:06 +08:00
Simon Glass
67c4e9f815 common: Move board_get_usable_ram_top() out of common.h
Move this function into init.h which seems to be designed for this sort
of thing. Also update the header to declare struct global_data so that it
can be included without global_data.h being needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:25:04 -05:00
Simon Glass
36bf446b64 common: Move enable/disable_interrupts out of common.h
Move these two functions into the irq_funcs.h header file. Also move
interrupt_handler_t as this is used by the irq_install_handler() function.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:25:01 -05:00
Lukas Auer
8c59f2023c riscv: add SPL support
U-Boot SPL on the generic RISC-V CPU supports two boot flows, directly
jumping to the image and via OpenSBI firmware. In the first case, both
U-Boot SPL and proper must be compiled to run in the same privilege
mode. Using OpenSBI firmware, U-Boot SPL must be compiled for machine
mode and U-Boot proper for supervisor mode.

To be able to use SPL, boards have to provide a supported SPL boot
device.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-08-26 16:07:42 +08:00
Lukas Auer
fbfd92bf9b riscv: add run mode configuration for SPL
U-Boot SPL can be run in a different privilege mode from U-Boot proper.
Add new configuration entries for SPL to allow the run mode to be
configured independently of U-Boot proper.

Extend all uses of the CONFIG_RISCV_SMODE and CONFIG_RISCV_MMODE
configuration symbols to also cover the SPL equivalents. Ensure that
files compatible with only one privilege mode are not included in builds
targeting an incompatible privilege mode.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-08-26 16:07:42 +08:00
Anup Patel
26f4fd1cb4 riscv: generic: Ensure that U-Boot runs within 4GB for 64bit systems
On 64bit systems, the DRAM top can be easily beyond 4GB and U-Boot
DMA mapping APIs will generate DMA addresses beyond 4GB. This
breaks DMA programming in 32bit DMA capable devices (such as
Cadence MACB ethernet). For example, If DRAM is more then 2GB
on QEMU sifive_u machine then Cadence MACB ethernet stops working
for U-Boot because it is a 32bit DMA capable device.

To handle 32bit DMA capable devices on 64bit systems, we provide
custom implementation of board_get_usable_ram_top() which ensures
that usable ram top is not more then 4GB. This in-turn ensures
that U-Boot always runs within 4GB hence DMA addresses generated
by DMA mapping APIs will be within 4GB too.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-02-27 09:12:33 +08:00
Anup Patel
fdff1f96a6 riscv: Rename cpu/qemu to cpu/generic
The QEMU CPU support under arch/riscv is pretty much generic
and works fine for SiFive Unleashed as well. In fact, there
will be quite a few RISC-V SOCs for which QEMU CPU support
will work fine.

This patch renames cpu/qemu to cpu/generic to indicate the
above fact. If there are SOC specific errata workarounds
required in cpu/generic then those can be done at runtime
in cpu/generic based on CPU vendor specific DT compatible
string.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-02-27 09:12:33 +08:00