Hello, I wonder how to map a device to the kernel where the first 3 bytes are not 0. Like the UART device which is phyically connected to 0x02530c00. The abort handler in pte_pte_small_new() get called when the first 3 bytes are not 0 (on this SoC are the first 3 bytes for the UART c00). Any advice how to deal with this? Thanks in advance! - Wladi 2017-01-25 22:22 GMT+01:00 Wladislav Wiebe :

Hi Alex,

...

A trick that I use to overcome this problem is to introduce a global variable that reflects the status of the PD. The UART driver then switches between the physical and virtual address of the UART as required.

that's it - seems before kernel activates the PD, Kernel might run into assertion which wants to print. I've changed the UART driver like --- a/src/plat/keystone/machine/io.c +++ b/src/plat/keystone/machine/io.c @@ -18,14 +18,19 @@ #define ULSR 0x14 /* UART Line Status Register */ #define ULSR_THRE BIT(5) /* Transmit Holding Register Empty */

-#define UART_REG(x) ((volatile uint32_t *)(UART0_PPTR + (x))) +#define UART_REG(x,uart_addr) ((volatile uint32_t *)(uart_addr + (x)))

#if defined(CONFIG_PRINTING) || defined(CONFIG_DEBUG_BUILD) void putDebugChar(unsigned char c) { - while ((*UART_REG(ULSR) & ULSR_THRE) == 0); - *UART_REG(UTHR) = c; + if (status_activate_global_pd) { + while ((*UART_REG(ULSR, UART0_PPTR) & ULSR_THRE) == 0); + *UART_REG(UTHR,UART0_PPTR) = c; + } else { + while ((*UART_REG(ULSR, UART0_PADDR) & ULSR_THRE) == 0); + *UART_REG(UTHR,UART0_PADDR) = c; + } } #endif

When running the machine now, I am at least able to see the assertion .. ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 paddr=[90000000..9048841f] ELF-loading image 'kernel' paddr=[80000000..8002ffff] vaddr=[e0000000..e002ffff] virt_entry=e0000000 ELF-loading image 'sel4test-driver' paddr=[80030000..80411fff] vaddr=[10000..3f1fff] virt_entry=1e920 Enabling MMU and paging Jumping to kernel-image entry point...

seL4 failed assertion '(address & ~0xfffff000ul) == ((0 && (address & (1ul << 31))) ? 0x0 : 0)' at ./arch/object/structures_gen.h:2495 in function pte_pte_small_new halting...

Thanks! - Wladi

2017-01-25 1:10 GMT+01:00 :

...

Hi Wladislav,

If the fault occurs before the activation of the kernel PD, this likely means that you are trying to printf before the UART is mapped.

If you are using printf for debugging before the PD is activated, you will need to change your kernel UART driver to use the physical address of the peripheral (the elfloader sets up unity mappings for 0x00000000-0xe0000000).

A trick that I use to overcome this problem is to introduce a global variable that reflects the status of the PD. The UART driver then switches between the physical and virtual address of the UART as required.

- Alex

On Tue, 2017-01-24 at 23:55 +0100, Wladislav Wiebe wrote:

...

Hi Alex,

thanks for pointing that out - I will double check the device mapping.

- Wladislav Wiebe

2017-01-24 23:24 GMT+01:00 :

...

A "Synchronous Data abort" occurs when a virtual memory translation fails on load/store operations. A "Prefetch abort" occurs when a virtual memory translation fails when loading instructions into the CPU pipeline. An "Asynchronous Data abort" occurs when a physical memory translation fails (ie, no RAM or peripheral is mapped to the physical address)

The address of the fault corresponds to a kernel device mapping. My guess is that you are not mapping kernel devices correctly at boot time: https://github.com/seL4/seL4/blob/master/include/plat/exynos5/plat/machine/d... https://github.com/seL4/seL4/blob/master/include/plat/exynos5/plat/machine/h... https://github.com/seL4/seL4/blob/master/src/arch/arm/32/machine/hardware.c#...

- Alex

On Tue, 2017-01-24 at 17:17 +0100, Wladislav Wiebe wrote:

...

could it be an TLB fault? For my understandig, based on http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438g/BABFFDF... it is the DFSR = 0x7 -> b00111 Translation fault, 2nd level.

Thanks! - Wladislav Wiebe

2017-01-24 15:42 GMT+01:00 Wladislav Wiebe :

...

Hello,

has somebody experience with running into arm_data_abort_exception after enabling the MMU/paging and jumping to the kernel image: .. ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 paddr=[90000000..904b041f] ELF-loading image 'kernel' paddr=[80000000..80033fff] vaddr=[f0000000..f0033fff] virt_entry=f0000000 ELF-loading image 'sel4test-driver' paddr=[80034000..8042dfff] vaddr=[10000..409fff] virt_entry=1e924 Enabling MMU and paging Jumping to kernel-image entry point...

check_data_abort_exception() DFAR = 0xfff01014 DFSR = 0x7 ADFSR = 0x0 abort() called.

I've dumped the DFAR/DFSR register --

Relevant config parts about the setup: CONFIG_ARCH_ARM_V7A=y CONFIG_ARCH_ARM=y CONFIG_ARCH_AARCH32=y CONFIG_ARM_CORTEX_A15=y CONFIG_PLAT_KEYSTONE=y

Thanks in advance! -- WBR, Wladislav WIebe

-- WBR, Wladislav WIebe

-- WBR, Wladislav WIebe

Hi Alex, when configuring the device like: devices.h #define UART0_PPTR 0xfff01c00 #define UART0_PADDR 0x02530000 hardware.h UART0_PADDR, UART0_PPTR, io.c putDebugChar(unsigned char c) { if (status_activate_global_pd) { while ((*UART_REG(ULSR, (UART0_PPTR)) & ULSR_THRE) == 0); *UART_REG(UTHR,(UART0_PPTR)) = c; } else { while ((*UART_REG(ULSR, (UART0_PADDR + 0xc00)) & ULSR_THRE) == 0); *UART_REG(UTHR,(UART0_PADDR + 0xc00)) = c; } } I can the the kernel successfully booting, but there is pretty early an crash in the userspace - memset(): seL4test/libs/libmuslc/src/string/memset.c:14 14930: e5431001 strb r1, [r3, #-1] So, I am still not sure if the device is correctly configured? ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 paddr=[c0008000..c049441f] ELF-loading image 'kernel' paddr=[81000000..8102efff] vaddr=[e0000000..e002efff] virt_entry=e0000000 ELF-loading image 'sel4test-driver' paddr=[8102f000..81411fff] vaddr=[10000..3f2fff] virt_entry=1e8d4 Enabling MMU and paging Jumping to kernel-image entry point... Bootstrapping kernel Caught cap fault in send phase at address 0x0 while trying to handle: vm fault on data at address 0xdf7fefff with status 0x805 in thread 0xffdfad00 "sel4test-driver" at address 0x14930 With stack: 0x2f2278: 0x7 0x2f227c: 0x1 0x2f2280: 0x2f22d0 0x2f2284: 0x2f2290 0x2f2288: 0x2d9ea4 0x2f228c: 0xdf7fe000 0x2f2290: 0x1 0x2f2294: 0x443 0x2f2298: 0x2dda68 0x2f229c: 0x5 0x2f22a0: 0xc 0x2f22a4: 0x0 0x2f22a8: 0x2d9ea4 0x2f22ac: 0x4f 0x2f22b0: 0x0 0x2f22b4: 0x1ba40 Thanks in advance! - Wladi 2017-01-27 21:52 GMT+01:00 :

Hi Wladi,

The addresses must be aligned to the size of the frame to be mapped. For a small page, it must be aligned to 0x1000. This is a requirement of the ARM hardware rather than the seL4 kernel.

The simple workaround is to add an additional offset to the mapped address. You can see how the issue was solved for imx6: https://github.com/seL4/seL4/blob/master/include/plat/imx6/plat/machine/devi...

- Alex

On Fri, 2017-01-27 at 16:40 +0100, Wladislav Wiebe wrote:

...

Hello,

I wonder how to map a device to the kernel where the first 3 bytes are not 0. Like the UART device which is phyically connected to 0x02530c00.

The abort handler in pte_pte_small_new() get called when the first 3 bytes are not 0 (on this SoC are the first 3 bytes for the UART c00).

Any advice how to deal with this?

Thanks in advance! - Wladi

2017-01-25 22:22 GMT+01:00 Wladislav Wiebe :

...

Hi Alex,

...

A trick that I use to overcome this problem is to introduce a global variable that reflects the status of the PD. The UART driver then switches between the physical and virtual address of the UART as required.

that's it - seems before kernel activates the PD, Kernel might run into assertion which wants to print. I've changed the UART driver like --- a/src/plat/keystone/machine/io.c +++ b/src/plat/keystone/machine/io.c @@ -18,14 +18,19 @@ #define ULSR 0x14 /* UART Line Status Register */ #define ULSR_THRE BIT(5) /* Transmit Holding Register Empty */

-#define UART_REG(x) ((volatile uint32_t *)(UART0_PPTR + (x))) +#define UART_REG(x,uart_addr) ((volatile uint32_t *)(uart_addr + (x)))

#if defined(CONFIG_PRINTING) || defined(CONFIG_DEBUG_BUILD) void putDebugChar(unsigned char c) { - while ((*UART_REG(ULSR) & ULSR_THRE) == 0); - *UART_REG(UTHR) = c; + if (status_activate_global_pd) { + while ((*UART_REG(ULSR, UART0_PPTR) & ULSR_THRE) == 0); + *UART_REG(UTHR,UART0_PPTR) = c; + } else { + while ((*UART_REG(ULSR, UART0_PADDR) & ULSR_THRE) == 0); + *UART_REG(UTHR,UART0_PADDR) = c; + } } #endif

When running the machine now, I am at least able to see the assertion .. ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 paddr=[90000000..9048841f] ELF-loading image 'kernel' paddr=[80000000..8002ffff] vaddr=[e0000000..e002ffff] virt_entry=e0000000 ELF-loading image 'sel4test-driver' paddr=[80030000..80411fff] vaddr=[10000..3f1fff] virt_entry=1e920 Enabling MMU and paging Jumping to kernel-image entry point...

seL4 failed assertion '(address & ~0xfffff000ul) == ((0 && (address & (1ul << 31))) ? 0x0 : 0)' at ./arch/object/structures_gen.h:2495 in function pte_pte_small_new halting...

Thanks! - Wladi

2017-01-25 1:10 GMT+01:00 :

...

Hi Wladislav,

If the fault occurs before the activation of the kernel PD, this likely means that you are trying to printf before the UART is mapped.

If you are using printf for debugging before the PD is activated, you will need to change your kernel UART driver to use the physical address of the peripheral (the elfloader sets up unity mappings for 0x00000000-0xe0000000).

A trick that I use to overcome this problem is to introduce a global variable that reflects the status of the PD. The UART driver then switches between the physical and virtual address of the UART as required.

- Alex

On Tue, 2017-01-24 at 23:55 +0100, Wladislav Wiebe wrote:

...

Hi Alex,

thanks for pointing that out - I will double check the device mapping.

- Wladislav Wiebe

2017-01-24 23:24 GMT+01:00 :

...

A "Synchronous Data abort" occurs when a virtual memory translation fails on load/store operations. A "Prefetch abort" occurs when a virtual memory translation fails when loading instructions into the CPU pipeline. An "Asynchronous Data abort" occurs when a physical memory translation fails (ie, no RAM or peripheral is mapped to the physical address)

The address of the fault corresponds to a kernel device mapping. My guess is that you are not mapping kernel devices correctly at boot time: https://github.com/seL4/seL4/blob/master/include/plat/exynos5/plat/machine/d... https://github.com/seL4/seL4/blob/master/include/plat/exynos5/plat/machine/h... https://github.com/seL4/seL4/blob/master/src/arch/arm/32/machine/hardware.c#...

- Alex

On Tue, 2017-01-24 at 17:17 +0100, Wladislav Wiebe wrote: > could it be an TLB fault? For my understandig, based on > http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438g/BABFFDF... > it is the DFSR = 0x7 -> b00111 > Translation fault, 2nd level. > > > Thanks! > - Wladislav Wiebe > > 2017-01-24 15:42 GMT+01:00 Wladislav Wiebe : > > Hello, > > > > has somebody experience with running into arm_data_abort_exception > > after enabling the MMU/paging and jumping to the kernel image: > > .. > > ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 > > paddr=[90000000..904b041f] > > ELF-loading image 'kernel' > > paddr=[80000000..80033fff] > > vaddr=[f0000000..f0033fff] > > virt_entry=f0000000 > > ELF-loading image 'sel4test-driver' > > paddr=[80034000..8042dfff] > > vaddr=[10000..409fff] > > virt_entry=1e924 > > Enabling MMU and paging > > Jumping to kernel-image entry point... > > > > check_data_abort_exception() > > DFAR = 0xfff01014 > > DFSR = 0x7 > > ADFSR = 0x0 > > abort() called. > > > > I've dumped the DFAR/DFSR register -- > > > > Relevant config parts about the setup: > > CONFIG_ARCH_ARM_V7A=y > > CONFIG_ARCH_ARM=y > > CONFIG_ARCH_AARCH32=y > > CONFIG_ARM_CORTEX_A15=y > > CONFIG_PLAT_KEYSTONE=y > > > > > > Thanks in advance! > > -- > > WBR, Wladislav WIebe > > >

-- WBR, Wladislav WIebe

-- WBR, Wladislav WIebe

Hi Alex, you are right - it was the UART PADDR driver. I had to WA it like I did in the kernel. But it only works when I disabling L1 data cache. Now it looks like: .. Test BIND0001 passed Test suite passed. 202 tests passed. 202/202 tests passed. All is well in the universe. :-) So, some starting point for this board is made -- Thanks a lot for the support! - Wladi 2017-01-29 23:09 GMT+01:00 :

Hi Wladi,

seL4test is the foundation of our regression tests. If you have made it this far in the boot process, the issue is likely to reside in your platform dependent user space timer or UART driver.

0x805 corresponds with a level 1 translation fault. This means that there is no virtual address mapping for that address.

The question is, why is sel4test calling memset on address 0xdf7fefff? You may need to follow the call stack further to find out.

Another possible problem may be a creative platform-dependent cache configuration. If the address does have a mapping, perhaps it is not observable by the translation hardware. A quick way to rule this problem out is to disable caches. This can be done via a configuration parameter that can be changed with `make menuconfig`.

- Alex Kroh

On Sun, 2017-01-29 at 21:22 +0100, Wladislav Wiebe wrote:

...

Hi Alex,

when configuring the device like: devices.h #define UART0_PPTR 0xfff01c00 #define UART0_PADDR 0x02530000

hardware.h UART0_PADDR, UART0_PPTR,

io.c putDebugChar(unsigned char c) { if (status_activate_global_pd) { while ((*UART_REG(ULSR, (UART0_PPTR)) & ULSR_THRE) == 0); *UART_REG(UTHR,(UART0_PPTR)) Wladi= c; } else { while ((*UART_REG(ULSR, (UART0_PADDR + 0xc00)) & ULSR_THRE) == 0); *UART_REG(UTHR,(UART0_PADDR + 0xc00)) = c; } }

I can the the kernel successfully booting, but there is pretty early an crash in the userspace - memset(): seL4test/libs/libmuslc/src/string/memset.c:14 14930: e5431001 strb r1, [r3, #-1]

So, I am still not sure if the device is correctly configured?

ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 paddr=[c0008000..c049441f] ELF-loading image 'kernel' paddr=[81000000..8102efff] vaddr=[e0000000..e002efff] virt_entry=e0000000 ELF-loading image 'sel4test-driver' paddr=[8102f000..81411fff] vaddr=[10000..3f2fff] virt_entry=1e8d4 Enabling MMU and paging Jumping to kernel-image entry point...

Bootstrapping kernel

Caught cap fault in send phase at address 0x0 while trying to handle: vm fault on data at address 0xdf7fefff with status 0x805 in thread 0xffdfad00 "sel4test-driver" at address 0x14930 With stack: 0x2f2278: 0x7 0x2f227c: 0x1 0x2f2280: 0x2f22d0 0x2f2284: 0x2f2290 0x2f2288: 0x2d9ea4 0x2f228c: 0xdf7fe000 0x2f2290: 0x1 0x2f2294: 0x443 0x2f2298: 0x2dda68 0x2f229c: 0x5 0x2f22a0: 0xc 0x2f22a4: 0x0 0x2f22a8: 0x2d9ea4 0x2f22ac: 0x4f 0x2f22b0: 0x0 0x2f22b4: 0x1ba40

Thanks in advance! - Wladi

2017-01-27 21:52 GMT+01:00 :

...

Hi Wladi,

The addresses must be aligned to the size of the frame to be mapped. For a small page, it must be aligned to 0x1000. This is a requirement of the ARM hardware rather than the seL4 kernel.

The simple workaround is to add an additional offset to the mapped address. You can see how the issue was solved for imx6: https://github.com/seL4/seL4/blob/master/include/plat/imx6/plat/machine/devi...

- Alex

On Fri, 2017-01-27 at 16:40 +0100, Wladislav Wiebe wrote:

...

Hello,

I wonder how to map a device to the kernel where the first 3 bytes are not 0. Like the UART device which is phyically connected to 0x02530c00.

The abort handler in pte_pte_small_new() get called when the first 3 bytes are not 0 (on this SoC are the first 3 bytes for the UART c00).

Any advice how to deal with this?

Thanks in advance! - Wladi

2017-01-25 22:22 GMT+01:00 Wladislav Wiebe :

...

Hi Alex,

...

A trick that I use to overcome this problem is to introduce a global variable that reflects the status of the PD. The UART driver then switches between the physical and virtual address of the UART as required.

that's it - seems before kernel activates the PD, Kernel might run into assertion which wants to print. I've changed the UART driver like --- a/src/plat/keystone/machine/io.c +++ b/src/plat/keystone/machine/io.c @@ -18,14 +18,19 @@ #define ULSR 0x14 /* UART Line Status Register */ #define ULSR_THRE BIT(5) /* Transmit Holding Register Empty */

-#define UART_REG(x) ((volatile uint32_t *)(UART0_PPTR + (x))) +#define UART_REG(x,uart_addr) ((volatile uint32_t *)(uart_addr + (x)))

#if defined(CONFIG_PRINTING) || defined(CONFIG_DEBUG_BUILD) void putDebugChar(unsigned char c) { - while ((*UART_REG(ULSR) & ULSR_THRE) == 0); - *UART_REG(UTHR) = c; + if (status_activate_global_pd) { + while ((*UART_REG(ULSR, UART0_PPTR) & ULSR_THRE) == 0); + *UART_REG(UTHR,UART0_PPTR) = c; + } else { + while ((*UART_REG(ULSR, UART0_PADDR) & ULSR_THRE) == 0); + *UART_REG(UTHR,UART0_PADDR) = c; + } } #endif

When running the machine now, I am at least able to see the assertion .. ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 paddr=[90000000..9048841f] ELF-loading image 'kernel' paddr=[80000000..8002ffff] vaddr=[e0000000..e002ffff] virt_entry=e0000000 ELF-loading image 'sel4test-driver' paddr=[80030000..80411fff] vaddr=[10000..3f1fff] virt_entry=1e920 Enabling MMU and paging Jumping to kernel-image entry point...

seL4 failed assertion '(address & ~0xfffff000ul) == ((0 && (address & (1ul << 31))) ? 0x0 : 0)' at ./arch/object/structures_gen.h:2495 in function pte_pte_small_new halting...

Thanks! - Wladi

2017-01-25 1:10 GMT+01:00 :

...

Hi Wladislav,

If the fault occurs before the activation of the kernel PD, this likely means that you are trying to printf before the UART is mapped.

If you are using printf for debugging before the PD is activated, you will need to change your kernel UART driver to use the physical address of the peripheral (the elfloader sets up unity mappings for 0x00000000-0xe0000000).

A trick that I use to overcome this problem is to introduce a global variable that reflects the status of the PD. The UART driver then switches between the physical and virtual address of the UART as required.

- Alex

On Tue, 2017-01-24 at 23:55 +0100, Wladislav Wiebe wrote: > Hi Alex, > > thanks for pointing that out - I will double check the device mapping. > > - Wladislav Wiebe > > 2017-01-24 23:24 GMT+01:00 : > > A "Synchronous Data abort" occurs when a virtual memory translation > > fails on load/store operations. > > A "Prefetch abort" occurs when a virtual memory translation fails when > > loading instructions into the CPU pipeline. > > An "Asynchronous Data abort" occurs when a physical memory translation > > fails (ie, no RAM or peripheral is mapped to the physical address) > > > > The address of the fault corresponds to a kernel device mapping. My > > guess is that you are not mapping kernel devices correctly at boot time: > > https://github.com/seL4/seL4/blob/master/include/plat/exynos5/plat/machine/d... > > https://github.com/seL4/seL4/blob/master/include/plat/exynos5/plat/machine/h... > > https://github.com/seL4/seL4/blob/master/src/arch/arm/32/machine/hardware.c#... > > > > > > - Alex > > > > On Tue, 2017-01-24 at 17:17 +0100, Wladislav Wiebe wrote: > >> could it be an TLB fault? For my understandig, based on > >> http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438g/BABFFDF... > >> it is the DFSR = 0x7 -> b00111 > >> Translation fault, 2nd level. > >> > >> > >> Thanks! > >> - Wladislav Wiebe > >> > >> 2017-01-24 15:42 GMT+01:00 Wladislav Wiebe : > >> > Hello, > >> > > >> > has somebody experience with running into arm_data_abort_exception > >> > after enabling the MMU/paging and jumping to the kernel image: > >> > .. > >> > ELF-loader started on CPU: ARM Ltd. Cortex-A15 r2p4 > >> > paddr=[90000000..904b041f] > >> > ELF-loading image 'kernel' > >> > paddr=[80000000..80033fff] > >> > vaddr=[f0000000..f0033fff] > >> > virt_entry=f0000000 > >> > ELF-loading image 'sel4test-driver' > >> > paddr=[80034000..8042dfff] > >> > vaddr=[10000..409fff] > >> > virt_entry=1e924 > >> > Enabling MMU and paging > >> > Jumping to kernel-image entry point... > >> > > >> > check_data_abort_exception() > >> > DFAR = 0xfff01014 > >> > DFSR = 0x7 > >> > ADFSR = 0x0 > >> > abort() called. > >> > > >> > I've dumped the DFAR/DFSR register -- > >> > > >> > Relevant config parts about the setup: > >> > CONFIG_ARCH_ARM_V7A=y > >> > CONFIG_ARCH_ARM=y > >> > CONFIG_ARCH_AARCH32=y > >> > CONFIG_ARM_CORTEX_A15=y > >> > CONFIG_PLAT_KEYSTONE=y > >> > > >> > > >> > Thanks in advance! > >> > -- > >> > WBR, Wladislav WIebe > >> > >> > >> > > > > >

-- WBR, Wladislav WIebe

-- WBR, Wladislav WIebe