On 08/11/2016 11:31 AM, Aleksey Makarov wrote: > 'ARM Server Base Boot Requirements' [1] mentions SPCR (Serial Port Console > Redirection Table) [2] as a mandatory ACPI table that specifies the > configuration of serial console. > > Move "earlycon" early_param handling to earlycon.c to parse this option once > > Parse SPCR table, setup earlycon and register specified console. > > Enable parsing this table on ARM64. Earlycon should be set up as early as > possible. ACPI boot tables are mapped in > arch/arm64/kernel/acpi.c:acpi_boot_table_init() called from setup_arch() and > that's where we parse spcr. So it has to be opted-in per-arch. When > ACPI_SPCR_TABLE is defined initialization of DT earlycon is deferred until the > DT/ACPI decision is done. > > Implement console_match() for pl011. > > Based on the work by Leif Lindholm [3] > Thanks to Peter Hurley for explaining how this should work. > > Should be applied to v4.8-rc1 > Tested on QEMU and ThunderX. > SPCR support is included in QEMU's ARM64 mach-virt since 2.4 release.
Tested-by: Christopher Covington <c...@codeaurora.org> on the QDF2432 Thanks, Cov > v9: > - rebase to v4.8-rc1 > - fix compilation for !CONFIG_SERIAL_EARLYCON case > - add Acked-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com> for ACPI part > - move constant check out of loop (Yury Norov) > - add '\n' to info message > > v8: > - rebase to next-20160520 > - remove the patch "ACPICA: Headers: Add new constants for the DBG2 ACPI > table" > as it have got to linux-next > - add Acked-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>, Reviewed-by: > Peter Hurley <pe...@hurleysoftware.com> (but see below) > - fix the patch "serial: pl011: add console matching function". The patch by > Christopher Covington [4] specifies that SBSA uart does 32-bit access to > registers and this breaks the match function. In this series the function > was changed to match when SPCR specifies both mmio32 and mmio access. > I removed Acked-by: Greg from this patch because of these changes. > > v7: > https://lkml.kernel.org/g/1459431629-27934-1-git-send-email-aleksey.maka...@linaro.org > - add Acked-by: Rob Herring for "of/serial: move earlycon early_param handling > to serial" > - call DT earlycon initialization from the arch ACPI code, not from > parse_spcr() > (Rafael J. Wysocki) > - fix a few minor issues (Rafael J. Wysocki) > > v6: > https://lkml.kernel.org/g/1458823925-19560-1-git-send-email-aleksey.maka...@linaro.org > - add documentation for parse_spcr() functioin (Yury Norov) > - don't initialize err variable (Yury Norov) > - add __initdata for the earlycon_init_is_deferred flag variable > - rename the function exported in "of/serial: move earlycon early_param > handling > to serial" to avoid clash with the function from > arch/microblaze/kernel/prom.c > - defer initialization of DT earlycon until DT/ACPI decision is made > (Rob Herring, Peter Hurley) > - use snprintf instead of sprintf (Andy Shevchenko) > - drop patch that adds EARLYCON_DECLARE for pl011 as EARLYCON_DECLARE is > equivalent to OF_EARLYCON_DECLARE for 4.6+ (Peter Hurley). This means that > SPCR earlycon will not work on the kernels before 4.6 > > v5: > https://lkml.kernel.org/g/1458643595-14719-1-git-send-email-aleksey.maka...@linaro.org > - drop patch "serial: pl011: use ACPI SPCR to setup 32-bit access" because > it is ugly. Also because Christopher Covington came with a better solution > [4] > - remove error message when the table is not provided by ACPI (Andy > Shevchenko) > - rewrite spcr.c following the suggestions by Peter Hurley > - add console_match() for pl011 in a separate patch > - add EARLYCON_DECLARE for pl011 in a separate patch > - add patch "of/serial: move earlycon early_param handling to serial" from > the GDB2 series > > v4: > https://lkml.kernel.org/g/1456747355-15692-1-git-send-email-aleksey.maka...@linaro.org > - drop patch "ACPI: change __init to __ref for early_acpi_os_unmap_memory()" > ACPI developers work on a new API and asked not to do that. > Instead, use acpi_get_table_with_size()/early_acpi_os_unmap_memory() once > and cache the result. (Lv Zheng) > - fix some style issues (Yury Norov) > > v3: > https://lkml.kernel.org/g/1455559532-8305-1-git-send-email-aleksey.maka...@linaro.org > > Greg Kroah-Hartman did not like v2 so I have rewritten this patchset: > > - drop acpi_match() member of struct console > - drop implementations of this member for pl011 and 8250 > - drop the patch that renames some vars in printk.c as it is not needed > anymore > - drop patch that introduces system wide acpi_table_parse2(). > Instead introduce a custom acpi_table_parse_spcr() in spcr.c > > Instead of introducing a new match_acpi() member of struct console, > this patchset introduces a new function acpi_console_check(). > This function is called when a new uart is registered at serial_core.c > the same way OF code checks for console. If the registered uart is the > console specified by SPCR table, this function calls add_preferred_console() > > The restrictions of this approach are: > > - only serial consoles can be set up > - only consoles specified by the memory/io address can be set up > (SPCR can specify devices by PCI id/PCI address) > > v2: > https://lkml.kernel.org/g/1455299022-11641-1-git-send-email-aleksey.maka...@linaro.org > - don't use SPCR if user specified console in command line > - fix initialization order of newcon->index = 0 > - rename some variables at printk.c (Joe Perches, Peter Hurley) > - enable ACPI_SPCR_TABLE in a separate patch (Andy Shevchenko) > - remove the retry loop for console registering (Peter Hurley). > Instead, obtain SPCR with acpi_get_table(). That works after > call to acpi_early_init() i. e. in any *_initcall() > - describe design decision behind introducing acpi_match() (Peter Hurley) > - fix compilation for x86 + ACPI (Graeme Gregory) > - introduce DBG2 constants in a separate patch (Andy Shevchenko) > - fix a typo in DBG2 constants (Andy Shevchenko) > - add ACPI_DBG2_ARM_SBSA_32BIT constant (Christopher Covington) > - add support for ACPI_DBG2_ARM_SBSA_* consoles (Christopher Covington) > - add documentation for functions > - add a patch that uses SPCR to find if SBSA serial driver should use 32-bit > accessor functions (Christopher Covington) > - change __init to __ref for early_acpi_os_unmap_memory() in a separate patch > - introduce acpi_table_parse2() in a separate patch > - fix fetching the SPCR table early (Mark Salter) > - add a patch from Mark Salter that introduces support for matching 8250-based > consoles > > v1: > https://lkml.kernel.org/g/1453722324-22407-1-git-send-email-aleksey.maka...@linaro.org > > [1] > http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0044a/index.html > [2] > https://msdn.microsoft.com/en-us/library/windows/hardware/dn639132(v=vs.85).aspx > [3] > https://lkml.kernel.org/g/1441716217-23786-1-git-send-email-leif.lindh...@linaro.org > [4] > https://lkml.kernel.org/g/1457415800-8799-1-git-send-email-...@codeaurora.org > > Aleksey Makarov (3): > ACPI: parse SPCR and enable matching console > ARM64: ACPI: enable ACPI_SPCR_TABLE > serial: pl011: add console matching function > > Leif Lindholm (1): > of/serial: move earlycon early_param handling to serial > > arch/arm64/Kconfig | 1 + > arch/arm64/kernel/acpi.c | 11 +++- > drivers/acpi/Kconfig | 3 ++ > drivers/acpi/Makefile | 1 + > drivers/acpi/spcr.c | 111 > ++++++++++++++++++++++++++++++++++++++++ > drivers/of/fdt.c | 11 +--- > drivers/tty/serial/amba-pl011.c | 56 ++++++++++++++++++++ > drivers/tty/serial/earlycon.c | 19 ++++++- > include/linux/acpi.h | 6 +++ > include/linux/of_fdt.h | 2 + > include/linux/serial_core.h | 9 +++- > 11 files changed, 216 insertions(+), 14 deletions(-) > create mode 100644 drivers/acpi/spcr.c > -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. 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