* [PATCH 1/3] target/i386: move linuxboot_dma_enabled to X86MachineState
2021-10-20 14:02 [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer Paolo Bonzini
@ 2021-10-20 14:02 ` Paolo Bonzini
2021-10-20 19:13 ` Philippe Mathieu-Daudé
2021-10-20 14:02 ` [PATCH 2/3] optionrom: add a DMA-enabled multiboot ROM Paolo Bonzini
` (2 subsequent siblings)
3 siblings, 1 reply; 8+ messages in thread
From: Paolo Bonzini @ 2021-10-20 14:02 UTC (permalink / raw)
To: qemu-devel; +Cc: adam, marcus.haehnel
This removes a parameter from x86_load_linux, and will avoid code
duplication between the linux and multiboot cases once multiboot
starts to support DMA.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
hw/i386/microvm.c | 5 ++++-
hw/i386/pc.c | 5 ++---
hw/i386/pc_piix.c | 3 ++-
hw/i386/pc_q35.c | 3 ++-
hw/i386/x86.c | 5 +++--
include/hw/i386/pc.h | 3 ---
include/hw/i386/x86.h | 5 +++--
7 files changed, 16 insertions(+), 13 deletions(-)
diff --git a/hw/i386/microvm.c b/hw/i386/microvm.c
index f257ec5a0b..837bafb64a 100644
--- a/hw/i386/microvm.c
+++ b/hw/i386/microvm.c
@@ -331,7 +331,7 @@ static void microvm_memory_init(MicrovmMachineState *mms)
rom_set_fw(fw_cfg);
if (machine->kernel_filename != NULL) {
- x86_load_linux(x86ms, fw_cfg, 0, true, true);
+ x86_load_linux(x86ms, fw_cfg, 0, true);
}
if (mms->option_roms) {
@@ -667,6 +667,7 @@ static void microvm_machine_initfn(Object *obj)
static void microvm_class_init(ObjectClass *oc, void *data)
{
+ X86MachineClass *x86mc = X86_MACHINE_CLASS(oc);
MachineClass *mc = MACHINE_CLASS(oc);
HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(oc);
@@ -697,6 +698,8 @@ static void microvm_class_init(ObjectClass *oc, void *data)
hc->unplug_request = microvm_device_unplug_request_cb;
hc->unplug = microvm_device_unplug_cb;
+ x86mc->fwcfg_dma_enabled = true;
+
object_class_property_add(oc, MICROVM_MACHINE_PIC, "OnOffAuto",
microvm_machine_get_pic,
microvm_machine_set_pic,
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 86223acfd3..d203db7845 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -775,7 +775,7 @@ void xen_load_linux(PCMachineState *pcms)
rom_set_fw(fw_cfg);
x86_load_linux(x86ms, fw_cfg, pcmc->acpi_data_size,
- pcmc->pvh_enabled, pcmc->linuxboot_dma_enabled);
+ pcmc->pvh_enabled);
for (i = 0; i < nb_option_roms; i++) {
assert(!strcmp(option_rom[i].name, "linuxboot.bin") ||
!strcmp(option_rom[i].name, "linuxboot_dma.bin") ||
@@ -927,7 +927,7 @@ void pc_memory_init(PCMachineState *pcms,
if (linux_boot) {
x86_load_linux(x86ms, fw_cfg, pcmc->acpi_data_size,
- pcmc->pvh_enabled, pcmc->linuxboot_dma_enabled);
+ pcmc->pvh_enabled);
}
for (i = 0; i < nb_option_roms; i++) {
@@ -1664,7 +1664,6 @@ static void pc_machine_class_init(ObjectClass *oc, void *data)
/* BIOS ACPI tables: 128K. Other BIOS datastructures: less than 4K reported
* to be used at the moment, 32K should be enough for a while. */
pcmc->acpi_data_size = 0x20000 + 0x8000;
- pcmc->linuxboot_dma_enabled = true;
pcmc->pvh_enabled = true;
pcmc->kvmclock_create_always = true;
assert(!mc->get_hotplug_handler);
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 6ad0d763c5..223dd3e05d 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -620,11 +620,12 @@ DEFINE_I440FX_MACHINE(v2_7, "pc-i440fx-2.7", NULL,
static void pc_i440fx_2_6_machine_options(MachineClass *m)
{
+ X86MachineClass *x86mc = X86_MACHINE_CLASS(m);
PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
pc_i440fx_2_7_machine_options(m);
pcmc->legacy_cpu_hotplug = true;
- pcmc->linuxboot_dma_enabled = false;
+ x86mc->fwcfg_dma_enabled = false;
compat_props_add(m->compat_props, hw_compat_2_6, hw_compat_2_6_len);
compat_props_add(m->compat_props, pc_compat_2_6, pc_compat_2_6_len);
}
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index fcc6e4eb2b..797e09500b 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -573,11 +573,12 @@ DEFINE_Q35_MACHINE(v2_7, "pc-q35-2.7", NULL,
static void pc_q35_2_6_machine_options(MachineClass *m)
{
+ X86MachineClass *x86mc = X86_MACHINE_CLASS(m);
PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
pc_q35_2_7_machine_options(m);
pcmc->legacy_cpu_hotplug = true;
- pcmc->linuxboot_dma_enabled = false;
+ x86mc->fwcfg_dma_enabled = false;
compat_props_add(m->compat_props, hw_compat_2_6, hw_compat_2_6_len);
compat_props_add(m->compat_props, pc_compat_2_6, pc_compat_2_6_len);
}
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index 76de7e2265..a34498fe16 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -764,9 +764,9 @@ static bool load_elfboot(const char *kernel_filename,
void x86_load_linux(X86MachineState *x86ms,
FWCfgState *fw_cfg,
int acpi_data_size,
- bool pvh_enabled,
- bool linuxboot_dma_enabled)
+ bool pvh_enabled)
{
+ bool linuxboot_dma_enabled = X86_MACHINE_GET_CLASS(x86ms)->fwcfg_dma_enabled;
uint16_t protocol;
int setup_size, kernel_size, cmdline_size;
int dtb_size, setup_data_offset;
@@ -1332,6 +1332,7 @@ static void x86_machine_class_init(ObjectClass *oc, void *data)
mc->possible_cpu_arch_ids = x86_possible_cpu_arch_ids;
x86mc->compat_apic_id_mode = false;
x86mc->save_tsc_khz = true;
+ x86mc->fwcfg_dma_enabled = true;
nc->nmi_monitor_handler = x86_nmi;
object_class_property_add(oc, X86_MACHINE_SMM, "OnOffAuto",
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 11426e26dc..9162aded21 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -116,9 +116,6 @@ struct PCMachineClass {
/* generate legacy CPU hotplug AML */
bool legacy_cpu_hotplug;
- /* use DMA capable linuxboot option rom */
- bool linuxboot_dma_enabled;
-
/* use PVH to load kernels that support this feature */
bool pvh_enabled;
diff --git a/include/hw/i386/x86.h b/include/hw/i386/x86.h
index 23267a3674..bb1cfb8896 100644
--- a/include/hw/i386/x86.h
+++ b/include/hw/i386/x86.h
@@ -38,6 +38,8 @@ struct X86MachineClass {
bool save_tsc_khz;
/* Enables contiguous-apic-ID mode */
bool compat_apic_id_mode;
+ /* use DMA capable linuxboot option rom */
+ bool fwcfg_dma_enabled;
};
struct X86MachineState {
@@ -120,8 +122,7 @@ void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
void x86_load_linux(X86MachineState *x86ms,
FWCfgState *fw_cfg,
int acpi_data_size,
- bool pvh_enabled,
- bool linuxboot_dma_enabled);
+ bool pvh_enabled);
bool x86_machine_is_smm_enabled(const X86MachineState *x86ms);
bool x86_machine_is_acpi_enabled(const X86MachineState *x86ms);
--
2.31.1
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH 1/3] target/i386: move linuxboot_dma_enabled to X86MachineState
2021-10-20 14:02 ` [PATCH 1/3] target/i386: move linuxboot_dma_enabled to X86MachineState Paolo Bonzini
@ 2021-10-20 19:13 ` Philippe Mathieu-Daudé
0 siblings, 0 replies; 8+ messages in thread
From: Philippe Mathieu-Daudé @ 2021-10-20 19:13 UTC (permalink / raw)
To: Paolo Bonzini, qemu-devel; +Cc: adam, marcus.haehnel
On 10/20/21 16:02, Paolo Bonzini wrote:
> This removes a parameter from x86_load_linux, and will avoid code
> duplication between the linux and multiboot cases once multiboot
> starts to support DMA.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> hw/i386/microvm.c | 5 ++++-
> hw/i386/pc.c | 5 ++---
> hw/i386/pc_piix.c | 3 ++-
> hw/i386/pc_q35.c | 3 ++-
> hw/i386/x86.c | 5 +++--
> include/hw/i386/pc.h | 3 ---
> include/hw/i386/x86.h | 5 +++--
> 7 files changed, 16 insertions(+), 13 deletions(-)
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 2/3] optionrom: add a DMA-enabled multiboot ROM
2021-10-20 14:02 [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer Paolo Bonzini
2021-10-20 14:02 ` [PATCH 1/3] target/i386: move linuxboot_dma_enabled to X86MachineState Paolo Bonzini
@ 2021-10-20 14:02 ` Paolo Bonzini
2021-10-20 22:08 ` Philippe Mathieu-Daudé
2021-10-20 14:02 ` [PATCH 3/3] target/i386: use DMA-enabled multiboot ROM for new-enough QEMU machine types Paolo Bonzini
2021-10-21 7:23 ` [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer Stefano Garzarella
3 siblings, 1 reply; 8+ messages in thread
From: Paolo Bonzini @ 2021-10-20 14:02 UTC (permalink / raw)
To: qemu-devel; +Cc: adam, marcus.haehnel
From: Marcus Hähnel <marcus.haehnel@kernkonzept.com>
Add a new option rom for the multiboot loader, using DMA transfers to copy
data instead of "rep insb".
This significantly lowers QEMU's startup latency by a factor of about 40,
for example, going from 30sec to 0.8sec when loading modules of 120MB
in size.
Signed-off-by: Marcus Hähnel <marcus.haehnel@kernkonzept.com>
Signed-off-by: Adam Lackorzynski <adam@l4re.org>
[Modified to keep the non-DMA code depending on #ifdef USE_FW_CFG_DMA;
do not write below stack. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
pc-bios/meson.build | 1 +
pc-bios/multiboot_dma.bin | Bin 0 -> 1024 bytes
pc-bios/optionrom/Makefile | 4 +-
pc-bios/optionrom/multiboot.S | 4 +-
pc-bios/optionrom/multiboot_dma.S | 2 +
pc-bios/optionrom/optionrom.h | 66 ++++++++++++++++++++++++++++++
6 files changed, 72 insertions(+), 5 deletions(-)
create mode 100644 pc-bios/multiboot_dma.bin
create mode 100644 pc-bios/optionrom/multiboot_dma.S
diff --git a/pc-bios/meson.build b/pc-bios/meson.build
index a44c9bc127..b40ff3f2bd 100644
--- a/pc-bios/meson.build
+++ b/pc-bios/meson.build
@@ -63,6 +63,7 @@ blobs = files(
'petalogix-s3adsp1800.dtb',
'petalogix-ml605.dtb',
'multiboot.bin',
+ 'multiboot_dma.bin',
'linuxboot.bin',
'linuxboot_dma.bin',
'kvmvapic.bin',
diff --git a/pc-bios/multiboot_dma.bin b/pc-bios/multiboot_dma.bin
new file mode 100644
index 0000000000000000000000000000000000000000..c0e2c3102a3358207c61d3ae113524fb6007abc3
GIT binary patch
literal 1024
zcmd^-v1=1i9LIlmUTlcNU1}{N5`u&{DAHSmq6iKdix;GHRxaNnR0A<Lc978Fk#IvN
zaS+5wQE+fL&*iQWa#czc94ZyL>R{3q;@~8~^LMo;4s!p158nI!-tWur_ul*P<{!&%
z=%3>xm5f`4Bq!!)`Rkwf;(oFd*qcAb=mhXX1)X>Bw-tylkUpR_ETXkH1AnO4L$nJ|
zWJui_M1kmKmTID)P`mI^=HM`~{VB1t1l_Ye=Lor4X5{8Gd)zzw_o4<6zLQJ!dr<pW
z;7%~ysSHL?*HHx*O%k}?fCyRL<7_RWt(4;Aqn}X}S>MolrKNZG2Z|kTOyaJIhYFc^
zFhhuQ9`r5fQLCrm#T4^_QylQ>8kgs;ZX9bIEiXb`8AIxu;?h~d%9izBkKht%WM1G*
z^E{W9(OT9dt5in2qF}|dPH>dL>{=sV#-U1<quUb@YkIW%niI?8-7fCz#695e<V=WZ
zrVCY?W~`3Hw@^=cHALr#9F2GOTYJ;??9d*-Vbsi+;lz|<$jMX#;lr6ov3qKNLH7(W
z+>yFoWnOtw14D$&k*SUtsT%wS`ki@#&rUrnmtuDv`PtJm(Kg?H$Pdc0CL@YCy4R<D
pT|LnIbg(BnP0#tqRx5M!bkkaD-nd?`H;YU4Yi6yHwD{k({tHC8FAx9#
literal 0
HcmV?d00001
diff --git a/pc-bios/optionrom/Makefile b/pc-bios/optionrom/Makefile
index 3482508a86..5d55d25acc 100644
--- a/pc-bios/optionrom/Makefile
+++ b/pc-bios/optionrom/Makefile
@@ -2,7 +2,7 @@ include config.mak
SRC_DIR := $(TOPSRC_DIR)/pc-bios/optionrom
VPATH = $(SRC_DIR)
-all: multiboot.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
+all: multiboot.bin multiboot_dma.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
# Dummy command so that make thinks it has done something
@true
@@ -41,8 +41,6 @@ override CFLAGS += $(call cc-option, $(Wa)-32)
LD_I386_EMULATION ?= elf_i386
override LDFLAGS = -m $(LD_I386_EMULATION) -T $(SRC_DIR)/flat.lds
-all: multiboot.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
-
pvh.img: pvh.o pvh_main.o
%.o: %.S
diff --git a/pc-bios/optionrom/multiboot.S b/pc-bios/optionrom/multiboot.S
index b7efe4de34..181a4b03a3 100644
--- a/pc-bios/optionrom/multiboot.S
+++ b/pc-bios/optionrom/multiboot.S
@@ -68,7 +68,7 @@ run_multiboot:
mov %eax, %es
/* Read the bootinfo struct into RAM */
- read_fw_blob(FW_CFG_INITRD)
+ read_fw_blob_dma(FW_CFG_INITRD)
/* FS = bootinfo_struct */
read_fw FW_CFG_INITRD_ADDR
@@ -188,7 +188,7 @@ prot_mode:
movl %eax, %gs
/* Read the kernel and modules into RAM */
- read_fw_blob(FW_CFG_KERNEL)
+ read_fw_blob_dma(FW_CFG_KERNEL)
/* Jump off to the kernel */
read_fw FW_CFG_KERNEL_ENTRY
diff --git a/pc-bios/optionrom/multiboot_dma.S b/pc-bios/optionrom/multiboot_dma.S
new file mode 100644
index 0000000000..d809af3e23
--- /dev/null
+++ b/pc-bios/optionrom/multiboot_dma.S
@@ -0,0 +1,2 @@
+#define USE_FW_CFG_DMA 1
+#include "multiboot.S"
diff --git a/pc-bios/optionrom/optionrom.h b/pc-bios/optionrom/optionrom.h
index a2b612f1a7..8d74c0ddf3 100644
--- a/pc-bios/optionrom/optionrom.h
+++ b/pc-bios/optionrom/optionrom.h
@@ -37,6 +37,17 @@
#define BIOS_CFG_IOPORT_CFG 0x510
#define BIOS_CFG_IOPORT_DATA 0x511
+#define FW_CFG_DMA_CTL_ERROR 0x01
+#define FW_CFG_DMA_CTL_READ 0x02
+#define FW_CFG_DMA_CTL_SKIP 0x04
+#define FW_CFG_DMA_CTL_SELECT 0x08
+#define FW_CFG_DMA_CTL_WRITE 0x10
+
+#define FW_CFG_DMA_SIGNATURE 0x51454d5520434647ULL /* "QEMU CFG" */
+
+#define BIOS_CFG_DMA_ADDR_HIGH 0x514
+#define BIOS_CFG_DMA_ADDR_LOW 0x518
+
/* Break the translation block flow so -d cpu shows us values */
#define DEBUG_HERE \
jmp 1f; \
@@ -62,6 +73,61 @@
bswap %eax
.endm
+
+/*
+ * Read data from the fw_cfg device using DMA.
+ * Clobbers: %edx, %eax, ADDR, SIZE, memory[%esp-16] to memory[%esp]
+ */
+.macro read_fw_dma VAR, SIZE, ADDR
+ /* Address */
+ bswapl \ADDR
+ pushl \ADDR
+
+ /* We only support 32 bit target addresses */
+ xorl %eax, %eax
+ pushl %eax
+ mov $BIOS_CFG_DMA_ADDR_HIGH, %dx
+ outl %eax, (%dx)
+
+ /* Size */
+ bswapl \SIZE
+ pushl \SIZE
+
+ /* Control */
+ movl $(\VAR << 16) | (FW_CFG_DMA_CTL_READ | FW_CFG_DMA_CTL_SELECT), %eax
+ bswapl %eax
+ pushl %eax
+
+ movl %esp, %eax /* Address of the struct we generated */
+ bswapl %eax
+ mov $BIOS_CFG_DMA_ADDR_LOW, %dx
+ outl %eax, (%dx) /* Initiate DMA */
+
+1: mov (%esp), %eax /* Wait for completion */
+ bswapl %eax
+ testl $~FW_CFG_DMA_CTL_ERROR, %eax
+ jnz 1b
+ addl $16, %esp
+.endm
+
+
+/*
+ * Read a blob from the fw_cfg device using DMA
+ * Requires _ADDR, _SIZE and _DATA values for the parameter.
+ *
+ * Clobbers: %eax, %edx, %es, %ecx, %edi and adresses %esp-20 to %esp
+ */
+#ifdef USE_FW_CFG_DMA
+#define read_fw_blob_dma(var) \
+ read_fw var ## _SIZE; \
+ mov %eax, %ecx; \
+ read_fw var ## _ADDR; \
+ mov %eax, %edi ;\
+ read_fw_dma var ## _DATA, %ecx, %edi
+#else
+#define read_fw_blob_dma(var) read_fw_blob(var)
+#endif
+
#define read_fw_blob_pre(var) \
read_fw var ## _SIZE; \
mov %eax, %ecx; \
--
2.31.1
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH 2/3] optionrom: add a DMA-enabled multiboot ROM
2021-10-20 14:02 ` [PATCH 2/3] optionrom: add a DMA-enabled multiboot ROM Paolo Bonzini
@ 2021-10-20 22:08 ` Philippe Mathieu-Daudé
0 siblings, 0 replies; 8+ messages in thread
From: Philippe Mathieu-Daudé @ 2021-10-20 22:08 UTC (permalink / raw)
To: Paolo Bonzini, qemu-devel; +Cc: adam, marcus.haehnel
On 10/20/21 16:02, Paolo Bonzini wrote:
> From: Marcus Hähnel <marcus.haehnel@kernkonzept.com>
>
> Add a new option rom for the multiboot loader, using DMA transfers to copy
> data instead of "rep insb".
>
> This significantly lowers QEMU's startup latency by a factor of about 40,
> for example, going from 30sec to 0.8sec when loading modules of 120MB
> in size.
>
> Signed-off-by: Marcus Hähnel <marcus.haehnel@kernkonzept.com>
> Signed-off-by: Adam Lackorzynski <adam@l4re.org>
> [Modified to keep the non-DMA code depending on #ifdef USE_FW_CFG_DMA;
> do not write below stack. - Paolo]
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> pc-bios/meson.build | 1 +
> pc-bios/multiboot_dma.bin | Bin 0 -> 1024 bytes
> pc-bios/optionrom/Makefile | 4 +-
> pc-bios/optionrom/multiboot.S | 4 +-
> pc-bios/optionrom/multiboot_dma.S | 2 +
> pc-bios/optionrom/optionrom.h | 66 ++++++++++++++++++++++++++++++
> 6 files changed, 72 insertions(+), 5 deletions(-)
> create mode 100644 pc-bios/multiboot_dma.bin
> create mode 100644 pc-bios/optionrom/multiboot_dma.S
> diff --git a/pc-bios/multiboot_dma.bin b/pc-bios/multiboot_dma.bin
> new file mode 100644
> index 0000000000000000000000000000000000000000..c0e2c3102a3358207c61d3ae113524fb6007abc3
> GIT binary patch
> literal 1024
> zcmd^-v1=1i9LIlmUTlcNU1}{N5`u&{DAHSmq6iKdix;GHRxaNnR0A<Lc978Fk#IvN
> zaS+5wQE+fL&*iQWa#czc94ZyL>R{3q;@~8~^LMo;4s!p158nI!-tWur_ul*P<{!&%
> z=%3>xm5f`4Bq!!)`Rkwf;(oFd*qcAb=mhXX1)X>Bw-tylkUpR_ETXkH1AnO4L$nJ|
> zWJui_M1kmKmTID)P`mI^=HM`~{VB1t1l_Ye=Lor4X5{8Gd)zzw_o4<6zLQJ!dr<pW
> z;7%~ysSHL?*HHx*O%k}?fCyRL<7_RWt(4;Aqn}X}S>MolrKNZG2Z|kTOyaJIhYFc^
> zFhhuQ9`r5fQLCrm#T4^_QylQ>8kgs;ZX9bIEiXb`8AIxu;?h~d%9izBkKht%WM1G*
> z^E{W9(OT9dt5in2qF}|dPH>dL>{=sV#-U1<quUb@YkIW%niI?8-7fCz#695e<V=WZ
> zrVCY?W~`3Hw@^=cHALr#9F2GOTYJ;??9d*-Vbsi+;lz|<$jMX#;lr6ov3qKNLH7(W
> z+>yFoWnOtw14D$&k*SUtsT%wS`ki@#&rUrnmtuDv`PtJm(Kg?H$Pdc0CL@YCy4R<D
> pT|LnIbg(BnP0#tqRx5M!bkkaD-nd?`H;YU4Yi6yHwD{k({tHC8FAx9#
Ideally this should be generated on CI as artifact, archived
and we commit the CI generated file.
> diff --git a/pc-bios/optionrom/optionrom.h b/pc-bios/optionrom/optionrom.h
> index a2b612f1a7..8d74c0ddf3 100644
> --- a/pc-bios/optionrom/optionrom.h
> +++ b/pc-bios/optionrom/optionrom.h
> @@ -37,6 +37,17 @@
> #define BIOS_CFG_IOPORT_CFG 0x510
> #define BIOS_CFG_IOPORT_DATA 0x511
>
> +#define FW_CFG_DMA_CTL_ERROR 0x01
> +#define FW_CFG_DMA_CTL_READ 0x02
> +#define FW_CFG_DMA_CTL_SKIP 0x04
> +#define FW_CFG_DMA_CTL_SELECT 0x08
> +#define FW_CFG_DMA_CTL_WRITE 0x10
> +
> +#define FW_CFG_DMA_SIGNATURE 0x51454d5520434647ULL /* "QEMU CFG" */
> +
> +#define BIOS_CFG_DMA_ADDR_HIGH 0x514
> +#define BIOS_CFG_DMA_ADDR_LOW 0x518
> +
> /* Break the translation block flow so -d cpu shows us values */
> #define DEBUG_HERE \
> jmp 1f; \
> @@ -62,6 +73,61 @@
> bswap %eax
> .endm
>
> +
> +/*
> + * Read data from the fw_cfg device using DMA.
> + * Clobbers: %edx, %eax, ADDR, SIZE, memory[%esp-16] to memory[%esp]
> + */
> +.macro read_fw_dma VAR, SIZE, ADDR
> + /* Address */
> + bswapl \ADDR
> + pushl \ADDR
> +
> + /* We only support 32 bit target addresses */
> + xorl %eax, %eax
> + pushl %eax
> + mov $BIOS_CFG_DMA_ADDR_HIGH, %dx
> + outl %eax, (%dx)
> +
> + /* Size */
> + bswapl \SIZE
> + pushl \SIZE
> +
> + /* Control */
Indent off.
> + movl $(\VAR << 16) | (FW_CFG_DMA_CTL_READ | FW_CFG_DMA_CTL_SELECT), %eax
> + bswapl %eax
> + pushl %eax
> +
> + movl %esp, %eax /* Address of the struct we generated */
> + bswapl %eax
> + mov $BIOS_CFG_DMA_ADDR_LOW, %dx
> + outl %eax, (%dx) /* Initiate DMA */
> +
> +1: mov (%esp), %eax /* Wait for completion */
> + bswapl %eax
> + testl $~FW_CFG_DMA_CTL_ERROR, %eax
> + jnz 1b
> + addl $16, %esp
Indent off.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 3/3] target/i386: use DMA-enabled multiboot ROM for new-enough QEMU machine types
2021-10-20 14:02 [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer Paolo Bonzini
2021-10-20 14:02 ` [PATCH 1/3] target/i386: move linuxboot_dma_enabled to X86MachineState Paolo Bonzini
2021-10-20 14:02 ` [PATCH 2/3] optionrom: add a DMA-enabled multiboot ROM Paolo Bonzini
@ 2021-10-20 14:02 ` Paolo Bonzini
2021-10-20 19:19 ` Philippe Mathieu-Daudé
2021-10-21 7:23 ` [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer Stefano Garzarella
3 siblings, 1 reply; 8+ messages in thread
From: Paolo Bonzini @ 2021-10-20 14:02 UTC (permalink / raw)
To: qemu-devel; +Cc: adam, marcus.haehnel
As long as fw_cfg supports DMA, the new ROM can be used also on older
machine types because it has the same size as the existing one.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
hw/i386/multiboot.c | 10 ++++++++--
hw/i386/multiboot.h | 4 +++-
hw/i386/pc.c | 3 ++-
hw/i386/x86.c | 2 +-
4 files changed, 14 insertions(+), 5 deletions(-)
diff --git a/hw/i386/multiboot.c b/hw/i386/multiboot.c
index 9e7d69d470..0a10089f14 100644
--- a/hw/i386/multiboot.c
+++ b/hw/i386/multiboot.c
@@ -143,7 +143,8 @@ static void mb_add_mod(MultibootState *s,
s->mb_mods_count++;
}
-int load_multiboot(FWCfgState *fw_cfg,
+int load_multiboot(X86MachineState *x86ms,
+ FWCfgState *fw_cfg,
FILE *f,
const char *kernel_filename,
const char *initrd_filename,
@@ -151,6 +152,7 @@ int load_multiboot(FWCfgState *fw_cfg,
int kernel_file_size,
uint8_t *header)
{
+ bool multiboot_dma_enabled = X86_MACHINE_GET_CLASS(x86ms)->fwcfg_dma_enabled;
int i, is_multiboot = 0;
uint32_t flags = 0;
uint32_t mh_entry_addr;
@@ -401,7 +403,11 @@ int load_multiboot(FWCfgState *fw_cfg,
fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, mb_bootinfo_data,
sizeof(bootinfo));
- option_rom[nb_option_roms].name = "multiboot.bin";
+ if (multiboot_dma_enabled) {
+ option_rom[nb_option_roms].name = "multiboot_dma.bin";
+ } else {
+ option_rom[nb_option_roms].name = "multiboot.bin";
+ }
option_rom[nb_option_roms].bootindex = 0;
nb_option_roms++;
diff --git a/hw/i386/multiboot.h b/hw/i386/multiboot.h
index 60de309cd1..2b9182a8ea 100644
--- a/hw/i386/multiboot.h
+++ b/hw/i386/multiboot.h
@@ -2,8 +2,10 @@
#define QEMU_MULTIBOOT_H
#include "hw/nvram/fw_cfg.h"
+#include "hw/i386/x86.h"
-int load_multiboot(FWCfgState *fw_cfg,
+int load_multiboot(X86MachineState *x86ms,
+ FWCfgState *fw_cfg,
FILE *f,
const char *kernel_filename,
const char *initrd_filename,
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index d203db7845..fcfb7f7139 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -780,7 +780,8 @@ void xen_load_linux(PCMachineState *pcms)
assert(!strcmp(option_rom[i].name, "linuxboot.bin") ||
!strcmp(option_rom[i].name, "linuxboot_dma.bin") ||
!strcmp(option_rom[i].name, "pvh.bin") ||
- !strcmp(option_rom[i].name, "multiboot.bin"));
+ !strcmp(option_rom[i].name, "multiboot.bin") ||
+ !strcmp(option_rom[i].name, "multiboot_dma.bin"));
rom_add_option(option_rom[i].name, option_rom[i].bootindex);
}
x86ms->fw_cfg = fw_cfg;
diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index a34498fe16..b84840a1bb 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -814,7 +814,7 @@ void x86_load_linux(X86MachineState *x86ms,
* PVH), so we try multiboot first since we check the multiboot magic
* header before to load it.
*/
- if (load_multiboot(fw_cfg, f, kernel_filename, initrd_filename,
+ if (load_multiboot(x86ms, fw_cfg, f, kernel_filename, initrd_filename,
kernel_cmdline, kernel_size, header)) {
return;
}
--
2.31.1
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer
2021-10-20 14:02 [PATCH v2 0/3] multiboot: Use DMA instead port-based transfer Paolo Bonzini
` (2 preceding siblings ...)
2021-10-20 14:02 ` [PATCH 3/3] target/i386: use DMA-enabled multiboot ROM for new-enough QEMU machine types Paolo Bonzini
@ 2021-10-21 7:23 ` Stefano Garzarella
3 siblings, 0 replies; 8+ messages in thread
From: Stefano Garzarella @ 2021-10-21 7:23 UTC (permalink / raw)
To: Paolo Bonzini; +Cc: adam, qemu-devel, marcus.haehnel
On Wed, Oct 20, 2021 at 04:02:41PM +0200, Paolo Bonzini wrote:
>An updated version of the patch at
>https://patchew.org/QEMU/YWM6jboU9fUib6Iy@os.inf.tu-dresden.de/,
>which includes the necessary glue for compatibility with older
>machine types. When fw_cfg DMA is disabled, the existing ROM
>is used instead.
>
>Marcus Hähnel (1):
> optionrom: add a DMA-enabled multiboot ROM
>
>Paolo Bonzini (2):
> target/i386: move linuxboot_dma_enabled to X86MachineState
> target/i386: use DMA-enabled multiboot ROM for new-enough QEMU machine
> types
>
> hw/i386/microvm.c | 5 ++-
> hw/i386/multiboot.c | 10 ++++-
> hw/i386/multiboot.h | 4 +-
> hw/i386/pc.c | 8 ++--
> hw/i386/pc_piix.c | 3 +-
> hw/i386/pc_q35.c | 3 +-
> hw/i386/x86.c | 7 ++--
> include/hw/i386/pc.h | 3 --
> include/hw/i386/x86.h | 5 ++-
> pc-bios/meson.build | 1 +
> pc-bios/multiboot_dma.bin | Bin 0 -> 1024 bytes
> pc-bios/optionrom/Makefile | 4 +-
> pc-bios/optionrom/multiboot.S | 4 +-
> pc-bios/optionrom/multiboot_dma.S | 2 +
> pc-bios/optionrom/optionrom.h | 66 ++++++++++++++++++++++++++++++
> 15 files changed, 102 insertions(+), 23 deletions(-)
> create mode 100644 pc-bios/multiboot_dma.bin
> create mode 100644 pc-bios/optionrom/multiboot_dma.S
>
>--
>2.31.1
>
>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
^ permalink raw reply [flat|nested] 8+ messages in thread