| Message ID | 1358436119-30808-3-git-send-email-shawn.guo@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Russell, On Thu, Jan 17, 2013 at 11:21:59PM +0800, Shawn Guo wrote: > arch/arm/boot/compressed/Makefile | 3 +++ > arch/arm/boot/compressed/debug.S | 3 +++ > arch/arm/include/debug/highbank.S | 3 +++ > arch/arm/include/debug/imx.S | 3 +++ > arch/arm/include/debug/mvebu.S | 3 +++ > arch/arm/include/debug/picoxcell.S | 3 +++ > arch/arm/include/debug/socfpga.S | 3 +++ > arch/arm/include/debug/sunxi.S | 3 +++ > arch/arm/include/debug/tegra.S | 3 +++ > arch/arm/include/debug/uncompress.h | 8 +++++++- > arch/arm/include/debug/vexpress.S | 3 +++ > arch/arm/include/debug/zynq.S | 3 +++ > 12 files changed, 40 insertions(+), 1 deletion(-) > create mode 100644 arch/arm/boot/compressed/debug.S > ... > diff --git a/arch/arm/boot/compressed/debug.S b/arch/arm/boot/compressed/debug.S > new file mode 100644 > index 0000000..7283d5c > --- /dev/null > +++ b/arch/arm/boot/compressed/debug.S > @@ -0,0 +1,3 @@ > +#define UNCOMPRESS_DEBUG > + > +#include "../../kernel/debug.S" > diff --git a/arch/arm/include/debug/highbank.S b/arch/arm/include/debug/highbank.S > index 8cad432..13056cf 100644 > --- a/arch/arm/include/debug/highbank.S > +++ b/arch/arm/include/debug/highbank.S > @@ -12,6 +12,9 @@ > .macro addruart,rp,rv,tmp > ldr \rv, =0xfee36000 > ldr \rp, =0xfff36000 > +#ifdef UNCOMPRESS_DEBUG > + mov \rv, \rp > +#endif > .endm > Are you fine with patching arch/arm/kernel/debug.S to have UNCOMPRESS_DEBUG checked, so that we can avoid patching addruart for all those platforms? Shawn
On Thursday 17 January 2013, Shawn Guo wrote: > However, there is a problem with above approach. DEBUG_LL routines > will check MMU enable bit to decide whether physical or virtual address > should be used to access debug port. In case virtual address needs > to be used, the address returned by addruart will not work for > decompressor who uses a different mapping from what kernel uses. > Fortunately, decompressor uses a flat mapping (same physical and virtual > addresses). So we can easily work it around by asking platform addruart > return physical address as virtual address when it runs in decompressor. > The macro UNCOMPRESS_DEBUG is defined for this use. Can't you just create a new copy of kernel/debug.S in boot/compressed/ that provides only a putc() function and uses the physical address unconditionally? For all I can tell, that should be little more than just #include CONFIG_DEBUG_LL_INCLUDE ENTRY(putc) addruart r1, r2, r3 waituart r3, r1 senduart r0, r1 busyuart r3, r1 mov pc,lr ENDPROC(putc) (I'm not sure about the actual semantics of the above, take that as an approximation) Arnd
On Thu, Jan 17, 2013 at 04:25:42PM +0000, Arnd Bergmann wrote: > On Thursday 17 January 2013, Shawn Guo wrote: > > However, there is a problem with above approach. DEBUG_LL routines > > will check MMU enable bit to decide whether physical or virtual address > > should be used to access debug port. In case virtual address needs > > to be used, the address returned by addruart will not work for > > decompressor who uses a different mapping from what kernel uses. > > Fortunately, decompressor uses a flat mapping (same physical and virtual > > addresses). So we can easily work it around by asking platform addruart > > return physical address as virtual address when it runs in decompressor. > > The macro UNCOMPRESS_DEBUG is defined for this use. > > Can't you just create a new copy of kernel/debug.S in boot/compressed/ > that provides only a putc() function and uses the physical address > unconditionally? > Why did I not think of this? The approach is obviously simpler. Please check the updated version I just sent out. Thanks. Shawn
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 5cad8a6..c9865f6 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -24,6 +24,9 @@ endif AFLAGS_head.o += -DTEXT_OFFSET=$(TEXT_OFFSET) HEAD = head.o OBJS += misc.o decompress.o +ifeq ($(CONFIG_DEBUG_LL),y) +OBJS += debug.o +endif FONTC = $(srctree)/drivers/video/console/font_acorn_8x8.c # string library code (-Os is enforced to keep it much smaller) diff --git a/arch/arm/boot/compressed/debug.S b/arch/arm/boot/compressed/debug.S new file mode 100644 index 0000000..7283d5c --- /dev/null +++ b/arch/arm/boot/compressed/debug.S @@ -0,0 +1,3 @@ +#define UNCOMPRESS_DEBUG + +#include "../../kernel/debug.S" diff --git a/arch/arm/include/debug/highbank.S b/arch/arm/include/debug/highbank.S index 8cad432..13056cf 100644 --- a/arch/arm/include/debug/highbank.S +++ b/arch/arm/include/debug/highbank.S @@ -12,6 +12,9 @@ .macro addruart,rp,rv,tmp ldr \rv, =0xfee36000 ldr \rp, =0xfff36000 +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm #include <asm/hardware/debug-pl01x.S> diff --git a/arch/arm/include/debug/imx.S b/arch/arm/include/debug/imx.S index 619d8cc..257f160 100644 --- a/arch/arm/include/debug/imx.S +++ b/arch/arm/include/debug/imx.S @@ -31,6 +31,9 @@ .macro addruart, rp, rv, tmp ldr \rp, =UART_PADDR @ physical ldr \rv, =UART_VADDR @ virtual +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm .macro senduart,rd,rx diff --git a/arch/arm/include/debug/mvebu.S b/arch/arm/include/debug/mvebu.S index 865c6d0..2024c1c 100644 --- a/arch/arm/include/debug/mvebu.S +++ b/arch/arm/include/debug/mvebu.S @@ -19,6 +19,9 @@ ldr \rv, =ARMADA_370_XP_REGS_VIRT_BASE orr \rp, \rp, #0x00012000 orr \rv, \rv, #0x00012000 +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm #define UART_SHIFT 2 diff --git a/arch/arm/include/debug/picoxcell.S b/arch/arm/include/debug/picoxcell.S index bc1f07c..0869efc 100644 --- a/arch/arm/include/debug/picoxcell.S +++ b/arch/arm/include/debug/picoxcell.S @@ -14,6 +14,9 @@ .macro addruart, rp, rv, tmp ldr \rv, =PHYS_TO_IO(PICOXCELL_UART1_BASE) ldr \rp, =PICOXCELL_UART1_BASE +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm #include "8250_32.S" diff --git a/arch/arm/include/debug/socfpga.S b/arch/arm/include/debug/socfpga.S index 966b2f9..0298e12 100644 --- a/arch/arm/include/debug/socfpga.S +++ b/arch/arm/include/debug/socfpga.S @@ -15,6 +15,9 @@ orr \rp, \rp, #0x00c00000 orr \rv, \rp, #0xfe000000 @ virtual base orr \rp, \rp, #0xff000000 @ physical base +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm #include "8250_32.S" diff --git a/arch/arm/include/debug/sunxi.S b/arch/arm/include/debug/sunxi.S index 04eb56d..5c40a3a 100644 --- a/arch/arm/include/debug/sunxi.S +++ b/arch/arm/include/debug/sunxi.S @@ -21,6 +21,9 @@ .macro addruart, rp, rv, tmp ldr \rp, =SUNXI_UART_DEBUG_PHYS_BASE ldr \rv, =SUNXI_UART_DEBUG_VIRT_BASE +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm #define UART_SHIFT 2 diff --git a/arch/arm/include/debug/tegra.S b/arch/arm/include/debug/tegra.S index 883d7c2..789fcb4 100644 --- a/arch/arm/include/debug/tegra.S +++ b/arch/arm/include/debug/tegra.S @@ -188,6 +188,9 @@ /* Load previously selected UART address */ 100: ldr \rp, [\tmp, #4] @ Load tegra_uart_phys ldr \rv, [\tmp, #8] @ Load tegra_uart_virt +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm /* diff --git a/arch/arm/include/debug/uncompress.h b/arch/arm/include/debug/uncompress.h index e19955d..b142a84 100644 --- a/arch/arm/include/debug/uncompress.h +++ b/arch/arm/include/debug/uncompress.h @@ -1,3 +1,9 @@ -static inline void putc(int c) {} +#ifdef CONFIG_DEBUG_LL +extern void printch(int c); +#else +static inline void printch(int c) {} +#endif + +static inline void putc(int c) { printch(c); } static inline void flush(void) {} static inline void arch_decomp_setup(void) {} diff --git a/arch/arm/include/debug/vexpress.S b/arch/arm/include/debug/vexpress.S index dc8e882..5015a01 100644 --- a/arch/arm/include/debug/vexpress.S +++ b/arch/arm/include/debug/vexpress.S @@ -43,6 +43,9 @@ orrne \rv, \rp, #DEBUG_LL_VIRT_BASE orrne \rp, \rp, #DEBUG_LL_PHYS_BASE_RS1 +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm #include <asm/hardware/debug-pl01x.S> diff --git a/arch/arm/include/debug/zynq.S b/arch/arm/include/debug/zynq.S index f9aa974..2795a64 100644 --- a/arch/arm/include/debug/zynq.S +++ b/arch/arm/include/debug/zynq.S @@ -35,6 +35,9 @@ .macro addruart, rp, rv, tmp ldr \rp, =LL_UART_PADDR @ physical ldr \rv, =LL_UART_VADDR @ virtual +#ifdef UNCOMPRESS_DEBUG + mov \rv, \rp +#endif .endm .macro senduart,rd,rx
Instead of providing a dummy uncompress.h and losing the uncompress debug capability completely for multiplatform build, the patch turns the uncompress debug into part of DEBUG_LL support. Thus, when DEBUG_LL is turned on for a particular platform, uncompress debug works too for that platform. To have the uncompress debug work, what most platforms need is only a putc() implementation. Meanwhile, DEBUG_LL infrastructural already has printch() there. We direct putc() call to printch() by creating arch/arm/boot/compressed/debug.S which simply includes arch/arm/kernel/debug.S. However, there is a problem with above approach. DEBUG_LL routines will check MMU enable bit to decide whether physical or virtual address should be used to access debug port. In case virtual address needs to be used, the address returned by addruart will not work for decompressor who uses a different mapping from what kernel uses. Fortunately, decompressor uses a flat mapping (same physical and virtual addresses). So we can easily work it around by asking platform addruart return physical address as virtual address when it runs in decompressor. The macro UNCOMPRESS_DEBUG is defined for this use. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> --- arch/arm/boot/compressed/Makefile | 3 +++ arch/arm/boot/compressed/debug.S | 3 +++ arch/arm/include/debug/highbank.S | 3 +++ arch/arm/include/debug/imx.S | 3 +++ arch/arm/include/debug/mvebu.S | 3 +++ arch/arm/include/debug/picoxcell.S | 3 +++ arch/arm/include/debug/socfpga.S | 3 +++ arch/arm/include/debug/sunxi.S | 3 +++ arch/arm/include/debug/tegra.S | 3 +++ arch/arm/include/debug/uncompress.h | 8 +++++++- arch/arm/include/debug/vexpress.S | 3 +++ arch/arm/include/debug/zynq.S | 3 +++ 12 files changed, 40 insertions(+), 1 deletion(-) create mode 100644 arch/arm/boot/compressed/debug.S