358 Commits

Author SHA1 Message Date
Anup Patel
db56341dfa lib: sbi: Allow platforms to provide root domain memory regions
Currently, the root domain memory regions are fixed in generic
code but some of the platforms may want to explicitly define
memory regions for the root domain.

This patch adds optional domains_root_regions() platform callback
which platforms can use to provide platform specific root domain
memory regions. Due to this changes, the root domain should also
undergo all sanity checks (just like regular domain) so we use
sbi_domain_register() to register root domain.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2021-01-12 10:41:11 +05:30
Vijai Kumar K
0d49c3bc18 lib: utils: Fix shakti uart implementation
Fix uart_putc implementation.
Due to a bug in the IP, this went unnoticed.
Use macros instead of magic numbers to make the code
more readable.

Signed-off-by: Vijai Kumar K <vijai@behindbytes.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2021-01-07 10:18:23 +05:30
Anup Patel
12394a269b lib: sbi: Allow custom local TLB flush function
Currently, we have fixed TLB flush types supported by the
remote TLB library. This approach is not flexible and does
not allow custom local TLB flush function. For example,
after updating PMP entries on a set of HARTs at runtime,
we have to flush TLB on these HARTs as well.

To support custom local TLB flush function, we replace the
"type" field of "struct sbi_tlb_info" with a local TLB flush
function pointer. We also provide definitions of standard TLB
flush operations (such as fence_i, sfence.vma, hfence.vvma,
hfence.gvma, etc).

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2021-01-07 09:53:19 +05:30
Anup Patel
b7df5e4392 lib: sbi: Introduce sbi_trap_exit() API
We introduce sbi_trap_exit() API which can help non-firmware
(i.e. generic or platform) code to force exit trap/interrupt
handling and resume execution at context pointed by parameter
"const struct sbi_trap_regs *regs".

This new sbi_trap_exit() API will help Keystone Enclave project
to resume execution of enclave from custom SBI call handler.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2021-01-07 09:53:17 +05:30
Anup Patel
80bc5065bb lib: sbi: Replace args with trap registers in ecall handler
We had added args pointer in ecall handler to ensure that ecall
handler only implements functionality and does not deal with
SBI calling convention. This also helped us to keep SBI calling
convention related code in one place at sbi_ecall_handler().

The Keystone Enclavce project needs access to the trap regsiters
in their ecall handler so that they can context switch enclaves
in custom SBI calls. To help the Keystone Enclave project, we
replace the args pointer in ecall handler parameter with a const
pointer to trap registers.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2021-01-07 09:53:14 +05:30
Anup Patel
7dcb1e1753 lib: sbi: Fix sign-extension in sbi_misaligned_load_handler()
The misaligned load emulation does not sign-extend values correctly
due to missing sign typecast in value passed to the SET_RD() macro.

A very easy way to reproduce this issue is to load 16-bit value
0xff1e from a byte aligned address using LH instruction on hardware
lacking misaligned load/store.

This patch fixes sbi_misaligned_load_handler() for above issue.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-24 16:35:28 +05:30
Anup Patel
a029bd90c6 lib: sbi: Remove domain_get() platform callback function
The domain_get() platform callback function is now redundant
because fdt_domain_populate() register new domain explicitly
using the sbi_domain_register() function.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-16 10:10:28 +05:30
Anup Patel
6fc1986f50 lib: utils: Remove fdt_domain_get() function
The fdt_domain_get() function is now redundant because the
fdt_domains_populate() function can explicitly register new
domains using the sbi_domain_register() function.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-16 10:10:25 +05:30
Anup Patel
7baccfca79 lib: sbi: Add function to register new domain
We add sbi_domain_register() function to help platform code register
a new domain explicitly instead of depending on domain_get() platform
callback. This function will eventually help us completely remove the
domain_get() platform callback.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-16 10:10:22 +05:30
Anup Patel
2179777364 lib: utils: Allow FDT domain iteration functions to fail
We extend fdt_iterate_each_domain() and fdt_iterate_each_memregion()
functions to allow underlying iteration function to fail. This will
help us catch more domain misconfiguration issues at boot time.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-16 10:10:19 +05:30
Dimitri John Ledkov
e7da0b4204 lib: utils/libfdt: Upgrade to v1.6.0 release
Sync with libfdt v1.6.0 release source codes.

Signed-off-by: Dimitri John Ledkov <xnox@ubuntu.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-12-13 09:52:25 +05:30
Anup Patel
ba741ea0ad lib: utils: Add helper routines to populate domains from FDT
We add various helper routines to populate domains, iterate domains,
iterate domain memregions, and parse HART to domain assignment from
the FDT.

These helper routines can be used by platform support code and FDT
fixup code.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 21:10:44 +05:30
Anup Patel
9b65dcaedd include: sbi: Add domains_init() platform operation
We introduce domains_init() platform operation which can be used by
platform support to initialize/populate domains in the coldboot path.

The domains_init() is called late in the coldboot sequence from the
sbi_domain_finalize() so sbi_printf() can be used by platform support
to print errors/warnings at time of populating domains.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 18:01:00 +05:30
Anup Patel
555e73778a lib: sbi: Add error prints in sbi_domain_finalize()
We add error prints in sbi_domain_finalize() and sanitize_domain()
to help debug domain configuration issues.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 18:00:04 +05:30
Anup Patel
62ea4f4e2a lib: sbi: Override domain boot HART when coldboot HART assigned to it
If coldboot HART is assigned to a domain then we should use coldboot
HART as the boot HART of the domain. This allows coldboot HART to
continue boot sequence even when it is assigned to some non-root domain.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 17:58:59 +05:30
Anup Patel
c709d40a67 lib: sbi: Auto start domain only if boot HART within limits
The sbi_domain_finalize() should auto start a domain only if the
boot HART is withing limits (i.e. less than SBI_HARTMASK_MAX_BITS).

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 17:57:46 +05:30
Anup Patel
4e370224df lib: sbi: Fix domain_count check in sbi_domain_finalize()
The domain_count check in sbi_domain_finalize() for newly discovered
domain is incorrect and should be reversed.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 17:57:15 +05:30
Anup Patel
3d921fad0d lib: sbi: Fix typo in sbi_domain_finalize()
There has been typo in automatic domain boot hart startup
for non-root domains so this patch fixes it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 17:56:43 +05:30
Anup Patel
8d2edc4fc9 lib: sbi: Fix sbi_hart_switch_mode() for u-mode
We should check and access N-extension CSRs in sbi_hart_switch_mode()
when next_mode is u-mode because N-extension is optional.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-04 17:56:10 +05:30
Anup Patel
548d03e577 lib: sbi: Implement System Reset (SRST) SBI extension
The SBI SRST extension has been accepted and merged in the latest
SBI v0.3-draft specification.
(Refer, https://github.com/riscv/riscv-sbi-doc)

It allows to S-mode software to request system shutdown, cold reboot,
and warm reboot.

This patch implements SBI SRST extension as a replacement of the
legacy sbi_shutdown() call of SBI v0.1 specification.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-01 17:11:11 +05:30
Anup Patel
5c429ae213 lib: sbi: Improve system reset platform operations
To implement the SBI SRST extension, we need two platform operations
for system reset:
1) system_reset_check() - This operation will check whether given
   reset type and reason are supported by the platform
2) system_reset() - This operation will do the actual platform
   system reset and it will not return if reset type and reason
   are supported by the platform

This patch updates system reset related code everywhere as-per above.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-01 17:10:31 +05:30
Anup Patel
c4acc60a46 include: sbi: Remove opensbi specific reset type defines
We can now use the standard SBI SRST extension reset types instead
of the opensbi specific (SBI_PLATFORM_RESET_xyz) reset types hence
remove related opensbi specific defines. The "platform_" prefix of
the reset type parameter of sbi_system_reset() function should also
be removed.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-01 17:05:12 +05:30
Anup Patel
48616b3de2 lib: sbi: Improve boot prints in cold boot sequence
Currently, we have all boot prints at the end of cold boot sequence
which means if there is any failure in cold boot sequence before
boot prints then we don't get any print.

This patch improves boot prints in cold boot sequence as follows:
1. We divide the boot prints into multiple parts and print it
   from different locations after sbi_console_init()
2. We throw an error print if there is any failure in cold boot
   sequence after sbi_console_init()

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-11-10 10:29:23 +05:30
Atish Patra
a809f406b9 lib: sbi: Improve boot time print with additional PMP information
We know about pmp granularity and number of bits supported by PMP.
Show those information in the boot time info print

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-26 22:59:09 +05:30
Atish Patra
bf21632860 lib: sbi: Detect PMP granularity and number of address bits
As per RISC-V privilege specification, a platform may choose to implement
a coarser granularity scheme for PMP addresses. In that case, we shouldn't
allow any pmp region size smaller than the platform supports. A platform
may not also implement all the bits for a PMP address specified in the priv
specification.

The pmp range granularity and address bits should be detected dynamically
before detecing PMP regions. Any pmp modification request beyond these detected
value must not succeed.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-26 22:44:52 +05:30
Atish Patra
74c0ea1e83 lib: utils: Implement "ranges" property parsing
The "reg" property in a device node may not be the correct address always.
If a parent node defines a "ranges" property, the child address need to be
translated with respect to parents address. If the ranges property is not
present, it will just use 1:1 translation.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-23 17:19:21 +05:30
Anup Patel
c347408a39 lib: sbi: Display domain details in boot prints
We extend boot prints to display details of each domain. In the
process, we remove sbi_hart_pmp_dump() because it shows redundant
information which domain details already show.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-21 12:01:34 +05:30
Anup Patel
c10c30b485 lib: sbi: Configure PMP based on domain memory regions
The PMP configuration on each HART should be only based on the memory
regions of the assigned domain because each domain includes a memory
region to protect the underlying firmware.

This patch updates the sbi_hart_pmp_configure() function accordingly.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:12:54 +05:30
Anup Patel
e856462ac2 lib: sbi: Remove redundant sbi_hart_pmp_xyz() functions
The sbi_hart_pmp_get() and sbi_hart_pmp_check_addr() functions
are not used anymore hence this patch removes these functions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:12:26 +05:30
Anup Patel
5fd99dbdaa lib: utils: Update fdt_cpu_fixup() to use current domain
The fdt_cpu_fixup() should disable a HART in DT if the HART
is not assigned to the current HART domain. This patch updates
fdt_cpu_fixup() accordingly.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:04:51 +05:30
Anup Patel
5edbb7cda1 lib: utils: Update fdt_reserved_memory_fixup() to use current domain
Now that each HART is mapped to a domain having a set of memory
regions, we update fdt_reserved_memory_fixup() to use domain memory
regions for adding reserved memory nodes in device tree.

We also change reserved memory node name prefix from "mmode_pmp"
to "mmode_resv" because domain memory regions can impact other
hardware configurations (such as IOPMP, etc) along with PMP.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:04:43 +05:30
Anup Patel
3e200370ee lib: sbi: Extend sbi_system_reset() for domains
The sbi_system_reset() should issue platform system reset only if
domain of current HART is allowed to do system reset.

This patch extends sbi_system_reset() as-per above.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:03:40 +05:30
Anup Patel
530e95bd63 lib: sbi: Optimize sbi_hsm_hart_started_mask() implementation
Instead of calling sbi_hsm_hart_get_state() in a loop, we can simply
call a new inline __sbi_hsm_hart_get_state() which only takes "hartid"
and enforce domain checks using sbi_domain_assigned_hartmask().

This patch optimizes sbi_hsm_hart_started_mask() as-per above.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 14:00:06 +05:30
Anup Patel
3a30d2c34d lib: sbi: Extend sbi_hsm_hart_start() for domains
The sbi_hsm_hart_start() should consider the domain under which we
are trying to start the HART. This will help ensure that HART A can
start HART B only if both HARTs A and B belong to the same domain.

We also have a special case when we bring-up boot HART of non-root
domains in sbi_domain_finalize() where we should skip domain checks
in sbi_hsm_hart_start(). To achieve this, sbi_hsm_hart_start() should
do domain checks only when domain parameter is non-NULL.

This patch extends sbi_hsm_hart_start() as-per above.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 13:56:36 +05:30
Anup Patel
e73b92d862 lib: sbi: Extend sbi_hsm_hart_started_mask() for domains
The sbi_hsm_hart_started_mask() API should take one more parameter
to allow caller specify domain under which started_mask is being
generated. Further, the sbi_hsm_hart_started_mask() depends on
sbi_hsm_hart_get_state() which also should return HART state under
specified domain.

This patch updates both sbi_hsm_hart_started_mask() and
sbi_hsm_hart_get_state() as-per above.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20 11:32:40 +05:30
Anup Patel
b1678af210 lib: sbi: Add initial domain support
An OpenSBI domain is a logical entity representing a set of HARTs
and a set of memory regions for these HARTs.

The OpenSBI domains support will allow OpenSBI platforms and previous
booting stage (i.e. U-Boot SPL, Coreboot, etc) to partition a system
into multiple domains where each domain will run it's own software.

For inter-domain isolation, OpenSBI will eventually use various HW
features such as PMP, ePMP, IOPMP, SiFive shield, etc but initial
implementation only use HW PMP support.

This patch provides initial implementation of OpenSBI domains where
we have a root/default domain and OpenSBI platforms can provide
non-root/custom domains using domain_get() callback.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20 11:22:15 +05:30
Anup Patel
f81d6f6f43 lib: sbi: Remove redundant hartid parameter from sbi_hart_init()
The hartid parameter of sbi_hart_init() is not used anywhere in
sbi_hart_init() implementation so let's remove it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20 11:18:28 +05:30
Anup Patel
a126886bfa lib: sbi: Configure PMP late in coldboot and warmboot path
We factor-out PMP configuration from sbi_hart_init() as a separate
sbi_hart_pmp_configure() function and do the PMP configuration very
late in coldboot and warmboot path just before platform_final_init().

Eventually, this enable us to configure PMP totally based on OpenSBI
domain where OpenSBI domains can be parsed from device-tree in any of
the platform operations except platform_final_init().

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20 11:18:03 +05:30
Anup Patel
a12d46a5e7 include: sbi: Remove pmp_region callbacks from sbi_platform_operations
The pmp_region_xyz() callbacks are not required in sbi_platform_operations
because we will be using OpenSBI domain memory regions to program the
PMP CSRs.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20 11:17:15 +05:30
Anup Patel
dbeeacb878 include: sbi: Remove redundant includes from sbi_platform.h
The sbi_ecall.h and sbi_trap.h are not required to be included in
sbi_platform.h hence we remove it. This way sources requiring
these headers will have to explicitly include it thereby reducing
implicit includes.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20 11:16:37 +05:30
Pragnesh Patel
7701ea13be lib: sbi: Fix PMP CSR detection
HiFive unleashed currently implements fewer than 56 bits of physical
address so existing PMP CSR detection is broken.

PMP address register encodes bits 55-2 of a 56-bit physical address,
Not all physical address bits may be implemented, So just check
minimum 1 bit.

Fixes: 74d1db7062 ("lib: sbi: Improve PMP CSR detection and
progamming")

Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-09-25 14:22:22 +05:30
Anup Patel
172fa1601c lib: sbi: Ensure coldboot HART supports next privilege mode
The coldboot HART jumps to the next booting stage at the end of
init_coldboot() so it is absolutely necessary for coldboot HART
to support the privilege mode expected by the next booting stage.

We extend the coldboot HART selection in sbi_init() to ensure that
the selected coldboot HART always supports privilege mode specified
in scratch space (i.e. scratch->next_mode). This will further help
us allow E-core (without MMU) on SiFive Unleashed and PolarFire
ICICLE boards to proceed further and wait in HSM STOPPED state.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-16 09:05:29 +05:30
Anup Patel
9f935a4a43 lib: utils: Improve fdt_cpu_fixup() implementation
The fdt_cpu_fixup() should work fine even if HARTs without MMU
are not marked invalid by platform support code.

In future, we plan to treat HARTs without MMU as valid in the
generic platform support so that we can hold these HARTs in
HSM STOPPED state.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-16 09:05:27 +05:30
Anup Patel
7ccf6bf54c lib: sbi: Allow specifying mode in sbi_hart_pmp_check_addr() API
We extend sbi_hart_pmp_check_addr() API so that users can specify
privilege mode of the address for checking PMP access permissions.

To achieve this, we end-up converting "unsigned long *size" parameter
to "unsigned long *log2len" for pmp_get() implementation so that we
can deal with regions of "1UL << __riscv_xlen" size in a special case
in sbi_hart_pmp_check_addr() implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-16 09:05:25 +05:30
Anup Patel
6734304f8c lib: sbi: Allow specifying start mode to sbi_hsm_hart_start() API
The sbi_scratch already has provision to specify the next stage mode
so we can leverage this to specify start mode to sbi_hsm_hart_start().

In future, this will be useful in providing SBI calls to U-mode on
embedded cores where we M-mode and U-mode but no S-mode.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-16 09:05:22 +05:30
Anup Patel
c1c7c3ee9e lib: sbi_trap: Allow M-mode to M-mode ECALLs
We should allow M-mode to M-mode ECALLs because:
1. No other mode can handle M-mode ECALLs
2. In future, we can allow M-mode baremetal application (not
   linked to OpenSBI) running independently and cooperatively
   without corrupting OpenSBI M-mode state (CSRs and memory).

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-09 09:32:04 +05:30
Anup Patel
bef63d6848 include: Rename ECALL defines to match latest RISC-V spec
We rename CAUSE_HYPERVISOR_ECALL to CAUSE_SUPERVISOR_ECALL and
CAUSE_SUPERVISOR_ECALL to CAUSE_VIRTUAL_SUPERVISOR_ECALL so that
it matches latest RISC-V privilege spec.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-09 09:32:02 +05:30
Anup Patel
dcb10c0056 lib: sbi: Don't handle VS-mode ecall in sbi_trap_handler()
The VS-mode ecall is supposed to be handled by HS-mode so
sbi_trap_handler() should fallback to default case for
VS-mode ecall trap.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-09 09:32:00 +05:30
Anup Patel
ebc8ebc0f8 lib: sbi: Improve HPM CSR read/write emulation
We improve HPM CSR read/write emulation as follows:
1. Fail for unimplemented counters so that trap is redirected
   to S-mode which can further help debugging S-mode software.
2. Check permissions in both MCOUNTEREN and SCOUNTEREN for
   HS-mode and U-mode.
3. Don't check permissions for TIME CSR because we emulate
   TIME CSR for both Host (HS/U-mode) and Guest (VS/VU-mode).
   Also, faster TIME CSR read is very helpful for good
   performance of S-mode software.
4. Don't emulate S-mode CSR read/write to M-mode HPM CSRs
   because these should not be accessible to S-mode software.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-01 10:28:35 +05:30
Anup Patel
2c341f7844 lib: sbi: Detect and print MHPM counters at boot-time
A RISC-V platform can leave unimplemented MHPM counters hard-wired
to zero. We extend hart_detect_features() to detect MHPM counters
which are accessible and not hard-wired to zero. We also print
number of available MHPM counters as part of boot prints.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-01 10:28:31 +05:30