On Tue, Sep 15, 2015 at 03:44:41PM +0100, Leif Lindholm wrote:
> Add a DBG2 table, describing the pl011 UART.
>
> Signed-off-by: Leif Lindholm <leif.lindh...@linaro.org>
> ---
> hw/arm/virt-acpi-build.c | 88
> +++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 87 insertions(+), 1 deletion(-)
>
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index 9088248..763d531 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -351,6 +351,89 @@ build_rsdp(GArray *rsdp_table, GArray *linker, unsigned
> rsdt)
> return rsdp_table;
> }
>
> +static int
> +dbg2_addresses_size(int num_addr)
> +{
> + return num_addr * (sizeof(struct AcpiGenericAddress) + sizeof(uint32_t));
> +}
> +
> +static int
> +dbg2_dev_length(int num_addr, const char *namepath, int oemdata_length)
> +{
> + int size;
> +
> + size = sizeof(AcpiDebugPort2Device);
> + size += dbg2_addresses_size(num_addr);
> + size += strlen(namepath) + 1;
> + size += oemdata_length;
> +
> + return size;
> +}
I think macros should suffice for the above helpers.
> +
> +static void
> +build_dbg2(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
> +{
> + const MemMapEntry *uart_memmap = &guest_info->memmap[VIRT_UART];
> + AcpiDebugPort2Header *dbg2;
> + AcpiDebugPort2Device *dev;
> + struct AcpiGenericAddress *addr;
> + uint32_t *addr_size;
> + char *data;
> + const char namepath[] = ".";
> + int address_count, oem_length, table_revision, table_size;
> +
> + address_count = 1;
> + oem_length = 0;
> + table_revision = 0;
> + table_size = sizeof(*dbg2) + dbg2_dev_length(address_count, namepath,
> + oem_length);
> +
> + dbg2 = acpi_data_push(table_data, sizeof(*dbg2));
> + dbg2->devices_offset = sizeof(*dbg2);
> + dbg2->devices_count = 1;
> +
> + dev = acpi_data_push(table_data, sizeof(*dev));
> + dev->revision = table_revision;
dev->revision and table_revision are presumably independent. I think
they should both get their own explicit '= 0'. Doing so allows us to get
rid of the local variable. I actually find the local variables, which
are constants, a bit crufty, and would prefer to just see the numbers.
> + dev->length = cpu_to_le16(dbg2_dev_length(address_count, namepath,
> + oem_length));
> + dev->address_count = address_count;
> + dev->namepath_length = cpu_to_le16(strlen(namepath));
what happened to the strlen + 1
> + dev->namepath_offset = cpu_to_le16(sizeof(*dev) +
> + dbg2_addresses_size(address_count));
> + dev->oem_data_length = cpu_to_le16(oem_length);
> + if (oem_length) {
> + dev->oem_data_offset = cpu_to_le16(dbg2_dev_length(address_count,
> + namepath, 0));
> + } else {
> + dev->oem_data_offset = 0;
> + }
I wouldn't bother with the special oem_data handling now, since we don't
plan to use it. If somebody extends this function for nonzero oem_length
sometime, then they can deal with it.
> + dev->port_type = cpu_to_le16(0x8000); /* Serial */
> + dev->port_subtype = cpu_to_le16(0x3); /* ARM PL011 UART */
> + dev->base_address_offset = cpu_to_le16(sizeof(*dev));
> + dev->address_size_offset = cpu_to_le16(sizeof(*dev) +
> + address_count * sizeof(*addr));
Could create another macro for this offset calculation. Actually could add
a macro for each for consistency.
> +
> + addr = acpi_data_push(table_data, sizeof(*addr) * address_count);
> + addr->space_id = AML_SYSTEM_MEMORY;
> + addr->bit_width = 8;
> + addr->bit_offset = 0;
> + addr->access_width = 1;
> + addr->address = cpu_to_le64(uart_memmap->base);
> +
> + addr_size = acpi_data_push(table_data, sizeof(*addr_size) *
> address_count);
> + *addr_size = cpu_to_le32(sizeof(*addr));
> +
> + data = acpi_data_push(table_data, strlen(namepath) + 1);
After dropping the oem data handling code, then we can use a better name
than 'data' for this.
> + strcpy(data, namepath);
> +
> + if (oem_length) {
> + data = acpi_data_push(table_data, oem_length);
> + }
> +
> + build_header(linker, table_data, (void *)dbg2, "DBG2", table_size,
> + table_revision);
> +}
> +
> static void
> build_spcr(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
> {
> @@ -577,7 +660,7 @@ void virt_acpi_build(VirtGuestInfo *guest_info,
> AcpiBuildTables *tables)
> dsdt = tables_blob->len;
> build_dsdt(tables_blob, tables->linker, guest_info);
>
> - /* FADT MADT GTDT MCFG SPCR pointed to by RSDT */
> + /* FADT MADT GTDT MCFG DBG2 SPCR pointed to by RSDT */
> acpi_add_table(table_offsets, tables_blob);
> build_fadt(tables_blob, tables->linker, dsdt);
>
> @@ -591,6 +674,9 @@ void virt_acpi_build(VirtGuestInfo *guest_info,
> AcpiBuildTables *tables)
> build_mcfg(tables_blob, tables->linker, guest_info);
>
> acpi_add_table(table_offsets, tables_blob);
> + build_dbg2(tables_blob, tables->linker, guest_info);
> +
> + acpi_add_table(table_offsets, tables_blob);
> build_spcr(tables_blob, tables->linker, guest_info);
>
> /* RSDT is pointed to by RSDP */
> --
> 2.1.4
>
>
I liked Shannon's suggestion to use more acpi_data_pushing, which this
version provides, but, as we're making assumptions (only one device
and no OEM data), then I think we can further simplify this version.
Thanks,
drew
