[U-Boot] [PATCH 09/10] x86: Generate a valid MultiProcessor (MP) table
Bin Meng
bmeng.cn at gmail.com
Wed Jun 17 09:49:22 CEST 2015
Hi Simon,
On Tue, Jun 16, 2015 at 10:46 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi Bin,
>
> On 15 June 2015 at 02:00, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Implement a weak write_mp_table() to create a minimal working MP
>> table. This includes an MP floating table, a configuration table
>> header and all of the 5 base configuration table entries. The I/O
>> interrupt assignment table entry is created based on the same
>> information used in the creation of PIRQ routing table from device
>> tree. A check duplicated entry logic is applied to prevent writing
>> multiple I/O interrupt entries with the same information.
>>
>> Use a Kconfig option GENERATE_MP_TABLE to tell U-Boot whether we
>> need actually write the MP table at the F seg, just like we did for
>> PIRQ routing and SFI tables. With MP table existence, linux kernel
>> will switch to I/O APIC and local APIC to process all the peripheral
>> interrupts instead of 8259 PICs. This takes full advantage of the
>> multicore hardware and the SMP kernel.
>>
>> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
>> ---
>>
>> arch/x86/Kconfig | 8 +++
>> arch/x86/include/asm/mpspec.h | 10 +++
>> arch/x86/lib/mpspec.c | 147 ++++++++++++++++++++++++++++++++++++++++++
>> arch/x86/lib/tables.c | 5 ++
>> 4 files changed, 170 insertions(+)
>>
>> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
>> index 1aeae9d..d4b2772 100644
>> --- a/arch/x86/Kconfig
>> +++ b/arch/x86/Kconfig
>> @@ -319,6 +319,14 @@ config GENERATE_SFI_TABLE
>>
>> For more information, see http://simplefirmware.org
>>
>> +config GENERATE_MP_TABLE
>> + bool "Generate an MP (Multi-Processor) table"
>> + help
>> + Generate an MP (Multi-Processor) table for this board. The MP table
>> + provides a way for the operating system to support for symmetric
>> + multiprocessing as well as symmetric I/O interrupt handling with
>> + the local APIC and I/O APIC.
>> +
>> endmenu
>>
>> config MAX_PIRQ_LINKS
>> diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
>> index c489a58..e9e1a2a 100644
>> --- a/arch/x86/include/asm/mpspec.h
>> +++ b/arch/x86/include/asm/mpspec.h
>> @@ -431,4 +431,14 @@ void mp_write_compat_address_space(struct mp_config_table *mc, u8 busid,
>> */
>> u32 mptable_finalize(struct mp_config_table *mc);
>>
>> +/**
>> + * write_mp_table() - Write MP table
>> + *
>> + * This writes MP table at a given address.
>> + *
>> + * @addr: start address to write MP table
>> + * @return: end address of MP table
>> + */
>> +u32 write_mp_table(u32 addr);
>> +
>> #endif /* __ASM_MPSPEC_H */
>> diff --git a/arch/x86/lib/mpspec.c b/arch/x86/lib/mpspec.c
>> index 657df22..1e3523f 100644
>> --- a/arch/x86/lib/mpspec.c
>> +++ b/arch/x86/lib/mpspec.c
>> @@ -9,13 +9,17 @@
>> #include <common.h>
>> #include <cpu.h>
>> #include <dm.h>
>> +#include <fdtdec.h>
>> #include <asm/cpu.h>
>> +#include <asm/irq.h>
>> #include <asm/ioapic.h>
>> #include <asm/lapic.h>
>> #include <asm/mpspec.h>
>> #include <asm/tables.h>
>> #include <dm/uclass-internal.h>
>>
>> +DECLARE_GLOBAL_DATA_PTR;
>> +
>> struct mp_config_table *mp_write_floating_table(struct mp_floating_table *mf)
>> {
>> u32 mc;
>> @@ -236,3 +240,146 @@ u32 mptable_finalize(struct mp_config_table *mc)
>>
>> return end;
>> }
>> +
>> +static void mptable_add_isa_interrupts(struct mp_config_table *mc, int bus_isa,
>> + u32 apicid, int external_int2)
>> +{
>> + int i;
>> +
>> + mp_write_intsrc(mc, external_int2 ? MP_INT : MP_EXTINT,
>> + MP_IRQ_TRIGGER_EDGE | MP_IRQ_POLARITY_HIGH,
>> + bus_isa, 0, apicid, 0);
>> + mp_write_intsrc(mc, MP_INT, MP_IRQ_TRIGGER_EDGE | MP_IRQ_POLARITY_HIGH,
>> + bus_isa, 1, apicid, 1);
>> + mp_write_intsrc(mc, external_int2 ? MP_EXTINT : MP_INT,
>> + MP_IRQ_TRIGGER_EDGE | MP_IRQ_POLARITY_HIGH,
>> + bus_isa, 0, apicid, 2);
>> +
>> + for (i = 3; i < 16; i++)
>> + mp_write_intsrc(mc, MP_INT,
>> + MP_IRQ_TRIGGER_EDGE | MP_IRQ_POLARITY_HIGH,
>> + bus_isa, i, apicid, i);
>> +}
>> +
>> +static bool check_dup_entry(struct mpc_config_intsrc *intsrc_base,
>> + int entry_num, u8 bus, u8 device, u8 pin)
>
> Again can we avoid u8 on function parameters?
Yes, in v2.
> Also this one coudl use a comment.
>
OK.
>> +{
>> + struct mpc_config_intsrc *intsrc = intsrc_base;
>> + int i;
>> +
>> + for (i = 0; i < entry_num; i++) {
>> + if (intsrc->mpc_srcbus == bus &&
>> + intsrc->mpc_srcbusirq == ((device << 2) | (pin - 1)))
>> + break;
>> + intsrc++;
>> + }
>> +
>> + return (i == entry_num) ? false : true;
>> +}
>> +
>> +static void mptable_add_intsrc(struct mp_config_table *mc,
>> + int bus_isa, u32 apicid)
>> +{
>> + struct mpc_config_intsrc *intsrc_base;
>> + int intsrc_entries = 0;
>> + const void *blob = gd->fdt_blob;
>> + int node;
>> + int len, count;
>> + const u32 *cell;
>> + int i;
>> +
>> + /* Legacy Interrupts */
>> + debug("Writing ISA IRQs\n");
>> + mptable_add_isa_interrupts(mc, bus_isa, apicid, 0);
>> +
>> + /* Get I/O interrupt information from device tree */
>> + node = fdtdec_next_compatible(blob, 0, COMPAT_INTEL_IRQ_ROUTER);
>> + if (node < 0) {
>> + debug("%s: Cannot find irq router node\n", __func__);
>> + return;
>
> return -ENOENT
>
> (and it's caller should check for error)
>
OK
>> + }
>> +
>> + cell = fdt_getprop(blob, node, "intel,pirq-routing", &len);
>> + if (!cell)
>> + return;
>> +
>> + if ((len % sizeof(struct pirq_routing)) == 0)
>> + count = len / sizeof(struct pirq_routing);
>> + else
>> + return;
>> +
>> + intsrc_base = (struct mpc_config_intsrc *)mp_next_mpc_entry(mc);
>> +
>> + for (i = 0; i < count; i++) {
>> + struct pirq_routing pr;
>> +
>> + pr.bdf = fdt_addr_to_cpu(cell[0]);
>> + pr.pin = fdt_addr_to_cpu(cell[1]);
>> + pr.pirq = fdt_addr_to_cpu(cell[2]);
>> +
>> + if (check_dup_entry(intsrc_base, intsrc_entries,
>> + PCI_BUS(pr.bdf), PCI_DEV(pr.bdf), pr.pin)) {
>> + debug("found entry for bus %d device %d INT%c, skipping\n",
>> + PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
>> + 'A' + pr.pin - 1);
>> + cell += sizeof(struct pirq_routing) / sizeof(u32);
>> + continue;
>> + }
>> +
>> + /* PIRQ[A-H] are always connected to I/O APIC INTPIN#16-23 */
>> + mp_write_pci_intsrc(mc, MP_INT, PCI_BUS(pr.bdf),
>> + PCI_DEV(pr.bdf), pr.pin, apicid,
>> + pr.pirq + 16);
>> + intsrc_entries++;
>> + cell += sizeof(struct pirq_routing) / sizeof(u32);
>> + }
>> +}
>> +
>> +static void mptable_add_lintsrc(struct mp_config_table *mc, u32 bus_isa)
>> +{
>> + mp_write_lintsrc(mc, MP_EXTINT,
>> + MP_IRQ_TRIGGER_EDGE | MP_IRQ_POLARITY_HIGH,
>> + bus_isa, 0, MP_APIC_ALL, 0);
>> + mp_write_lintsrc(mc, MP_NMI,
>> + MP_IRQ_TRIGGER_EDGE | MP_IRQ_POLARITY_HIGH,
>> + bus_isa, 0, MP_APIC_ALL, 1);
>> +}
>> +
>> +__weak u32 write_mp_table(u32 addr)
>
> Why does this need to be weak?
>
I wanted to leave an option to have board-specific codes to implement
the writing of mp table by using the APIs provided in this file,
although I think this weak version could probably fit for 90% boards.
We can remove the weak for now, and see how things go?
[snip]
Regards,
Bin
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