u-boot.git/arch/microblaze/cpu, branch v2022.04

microblaze: exception: fix unaligned data access register mask

2022-02-15T12:11:43+00:00

The correct mask for getting the source/destination register from ESR in
the case of an unaligned access exception is 0x3E0. With this change, a
dummy unaligned store produces the expected info:
"""
>> swi r5, r0, 0x111

 ...
 Hardware exception at 0x111 address
 Unaligned data access exception
 Unaligned word access
 Unaligned store access
 Register R5
 Return address from exception 0x7f99dfc
 ### ERROR ### Please RESET the board ###
"""

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20220213080925.1548411-6-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: exception: move unaligned access printfs inside switch case

2022-02-15T12:11:43+00:00

The unaligned access messages are only valid in the case of an unaligned
data access exception. Do not print them for other types of hw exceptions.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20220213080925.1548411-5-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: exception: fix return address for delay slot exceptions

2022-02-15T12:11:43+00:00

According to the MicroBlaze reference manual (xilinx2021.2/ug984/page-37):
"""
If an exception is caused by an instruction in a delay slot (that is,
ESR[DS]=1), the exception handler should return execution to
the address stored in BTR instead of the normal exception return
address stored in R17.
"""

Adjust the code to print the proper return address for delay slot
exceptions.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20220213080925.1548411-4-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: exception: fix delay slot exception handling

2022-02-15T12:11:43+00:00

The switch statement in _hw_exception_handler() only covers the
rightmost 5 bits that encode the exception cause:
switch (state & 0x1f)
{
...
}

For this reason, the "0x1000" case will never be reached, because the 13th
bit was zeroed out. To fix this, move delay slot exception handling before
the switch statement (delay slot (DS) bit in Exception Status Register is
independent of the exception cause (EC)).

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20220213080925.1548411-3-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: exception: migrate MICROBLAZE_V5 to Kconfig

2022-02-15T12:11:43+00:00

Also, rename it to XILINX_MICROBLAZE0_DELAY_SLOT_EXCEP, since it only
covers delay slot exception support.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20220213080925.1548411-2-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: exception: move privileged instruction exception out of v5 ifdef

2022-02-15T12:11:43+00:00

The privileged instruction exception seems to have been introduced in
microblaze v7.00 along with MMU support, so having it wrapped in
MICROBLAZE_v5 ifdefs seems incorrect. Move it out of the ifdef, since all
recent microblaze versions support it.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20220213080925.1548411-1-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: branch to base vector address on reset

2022-01-05T09:22:03+00:00

Current code assumes that the vector base address is always at 0x0.
However, this value is configurable for MicroBlaze using the
CONFIG_XILINX_MICROBLAZE0_VECTOR_BASE_ADDR Kconfig option. Update the
reset routines to branch to this location instead.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20211130163358.2531677-10-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: start.S: add support for configurable vector base address

2022-01-05T09:22:03+00:00

Current code assumes that the vector base address is always at 0x0.
However, this value is configurable for MicroBlaze, so update the
__setup_exceptions routine to work with any vector base address.

The r4 register is reserved for the vector base address inside
__setup_exceptions and the function prologe/epilogue are also updated to
save and restore r4.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20211130163358.2531677-9-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: migrate CONFIG_SYS_USR_EXCEP to Kconfig

2022-01-05T09:22:03+00:00

Migrate CONFIG_SYS_USR_EXCEP to Kconfig. Also, rename it to
XILINX_MICROBLAZE0_USR_EXCEP in order to match the naming convention of
microblaze-generic Kconfig options.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20211130163358.2531677-7-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek

microblaze: drop CONFIG_SYS_RESET_ADDRESS macro

2022-01-05T09:22:03+00:00

Microblaze is one the last two users of the CONFIG_SYS_RESET_ADDRESS
macro (the other is arch/powerpc/cpu/mpc8xx/cpu.c, but the macro is not
defined anywhere in powerpc code, so it should be removed there too).

Replace CONFIG_SYS_RESET_ADDRESS usage in start.S with
CONFIG_SYS_TEXT_BASE. If the reset address should really be
user-configurable, a new Kconfig option could be added.

Signed-off-by: Ovidiu Panait 
Link: https://lore.kernel.org/r/20211130163358.2531677-6-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek