Commit Graph

4 Commits

Author SHA1 Message Date
Xu Lu
77a44196ab iommu/riscv: Add shutdown function for iommu driver
This commit supplies shutdown callback for iommu driver. The shutdown
callback resets necessary registers so that newly booted kernel can pass
riscv_iommu_init_check() after kexec. Also, the shutdown callback resets
iommu mode to bare instead of off so that new kernel can still use PCIE
devices even when CONFIG_RISCV_IOMMU is not enabled.

Signed-off-by: Xu Lu <luxu.kernel@bytedance.com>
Link: https://lore.kernel.org/r/20250103093220.38106-3-luxu.kernel@bytedance.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-01-06 12:38:11 +01:00
Tomasz Jeznach
856c0cfe5c iommu/riscv: Command and fault queue support
Introduce device command submission and fault reporting queues,
as described in Chapter 3.1 and 3.2 of the RISC-V IOMMU Architecture
Specification.

Command and fault queues are instantiated in contiguous system memory
local to IOMMU device domain, or mapped from fixed I/O space provided
by the hardware implementation. Detection of the location and maximum
allowed size of the queue utilize WARL properties of queue base control
register. Driver implementation will try to allocate up to 128KB of
system memory, while respecting hardware supported maximum queue size.

Interrupts allocation is based on interrupt vectors availability and
distributed to all queues in simple round-robin fashion. For hardware
Implementation with fixed event type to interrupt vector assignment
IVEC WARL property is used to discover such mappings.

Address translation, command and queue fault handling in this change
is limited to simple fault reporting without taking any action.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/c4735fb6829053eff37ce1bcca4906192afd743c.1729059707.git.tjeznach@rivosinc.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-10-29 09:46:29 +01:00
Tomasz Jeznach
1bac10c557 iommu/riscv: Device directory management.
Introduce device context allocation and device directory tree
management including capabilities discovery sequence, as described
in Chapter 2.1 of the RISC-V IOMMU Architecture Specification.

Device directory mode will be auto detected using DDTP WARL property,
using highest mode supported by the driver and hardware. If none
supported can be configured, driver will fall back to global pass-through.

First level DDTP page can be located in I/O (detected using DDTP WARL)
and system memory.

Only simple identity and blocking protection domains are supported by
this implementation.

Co-developed-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/e1c763aeccd2c05fd4ad3a32f6f2ff3b3148d907.1729059707.git.tjeznach@rivosinc.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-10-29 09:46:28 +01:00
Tomasz Jeznach
5c0ebbd3c6 iommu/riscv: Add RISC-V IOMMU platform device driver
Introduce platform device driver for implementation of RISC-V IOMMU
architected hardware.

Hardware interface definition located in file iommu-bits.h is based on
ratified RISC-V IOMMU Architecture Specification version 1.0.0.

This patch implements platform device initialization, early check and
configuration of the IOMMU interfaces and enables global pass-through
address translation mode (iommu_mode == BARE), without registering
hardware instance in the IOMMU subsystem.

Link: https://github.com/riscv-non-isa/riscv-iommu
Co-developed-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Co-developed-by: Sebastien Boeuf <seb@rivosinc.com>
Signed-off-by: Sebastien Boeuf <seb@rivosinc.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Tomasz Jeznach <tjeznach@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/2f2e4530c0ee4a81385efa90f1da932f5179f3fb.1729059707.git.tjeznach@rivosinc.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-10-29 09:46:23 +01:00