Re: [PATCH] Xen: EFI: Parse DT parameters for Xen specific UEFI

From: Mathieu Poirier
Date: Fri May 06 2016 - 11:52:49 EST

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In reply to: Shannon Zhao: "[PATCH] Xen: EFI: Parse DT parameters for Xen specific UEFI"
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On 6 May 2016 at 02:32, Shannon Zhao <zhaoshenglong@xxxxxxxxxx> wrote:
> From: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
>
> Add a new function to parse DT parameters for Xen specific UEFI just
> like the way for normal UEFI. Then it could reuse the existing codes.
>
> If Xen supports EFI, initialize runtime services.
>
> CC: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> ---
> Drop using of EFI_PARAVIRT. Discussion can be found from [1].
> [1] https://lkml.org/lkml/2016/4/29/8
> ---
> arch/arm/include/asm/efi.h | 2 +
> arch/arm/xen/enlighten.c | 16 ++++++++
> arch/arm64/include/asm/efi.h | 2 +
> drivers/firmware/efi/arm-runtime.c | 70 +++++++++++++++++++++++---------
> drivers/firmware/efi/efi.c | 81 ++++++++++++++++++++++++++++++--------
> 5 files changed, 137 insertions(+), 34 deletions(-)
>
> diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h
> index e0eea72..5ba4343 100644
> --- a/arch/arm/include/asm/efi.h
> +++ b/arch/arm/include/asm/efi.h
> @@ -52,9 +52,11 @@ static inline void efi_set_pgd(struct mm_struct *mm)
>
> void efi_virtmap_load(void);
> void efi_virtmap_unload(void);
> +int xen_arm_enable_runtime_services(void);
>
> #else
> #define efi_init()
> +#define xen_arm_enable_runtime_services() (0)
> #endif /* CONFIG_EFI */
>
> /* arch specific definitions used by the stub code */
> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
> index 13e3e9f..3362870 100644
> --- a/arch/arm/xen/enlighten.c
> +++ b/arch/arm/xen/enlighten.c
> @@ -16,6 +16,7 @@
> #include <asm/xen/hypervisor.h>
> #include <asm/xen/hypercall.h>
> #include <asm/system_misc.h>
> +#include <asm/efi.h>
> #include <linux/interrupt.h>
> #include <linux/irqreturn.h>
> #include <linux/module.h>
> @@ -261,6 +262,13 @@ static int __init fdt_find_hyper_node(unsigned long node, const char *uname,
> !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix)))
> hyper_node.version = s + strlen(hyper_node.prefix);
>
> + if (IS_ENABLED(CONFIG_XEN_EFI)) {
> + /* Check if Xen supports EFI */
> + if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) &&
> + !efi_runtime_disabled())
> + set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
> + }
> +
> return 0;
> }
>
> @@ -338,6 +346,7 @@ static int __init xen_guest_init(void)
> {
> struct xen_add_to_physmap xatp;
> struct shared_info *shared_info_page = NULL;
> + int ret;
>
> if (!xen_domain())
> return 0;
> @@ -352,6 +361,13 @@ static int __init xen_guest_init(void)
> return -ENODEV;
> }
>
> + if (IS_ENABLED(CONFIG_XEN_EFI) && efi_enabled(EFI_BOOT) &&
> + efi_enabled(EFI_RUNTIME_SERVICES)) {
> + ret = xen_arm_enable_runtime_services();
> + if (ret)
> + return ret;
> + }
> +
> shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL);
>
> if (!shared_info_page) {
> diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
> index 8e88a69..574bee5 100644
> --- a/arch/arm64/include/asm/efi.h
> +++ b/arch/arm64/include/asm/efi.h
> @@ -8,8 +8,10 @@
>
> #ifdef CONFIG_EFI
> extern void efi_init(void);
> +int xen_arm_enable_runtime_services(void);
> #else
> #define efi_init()
> +#define xen_arm_enable_runtime_services() (0)
> #endif
>
> int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
> diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
> index 6ae21e4..211ec10 100644
> --- a/drivers/firmware/efi/arm-runtime.c
> +++ b/drivers/firmware/efi/arm-runtime.c
> @@ -27,6 +27,7 @@
> #include <asm/mmu.h>
> #include <asm/pgalloc.h>
> #include <asm/pgtable.h>
> +#include <asm/xen/xen-ops.h>
>
> extern u64 efi_system_table;
>
> @@ -39,6 +40,33 @@ static struct mm_struct efi_mm = {
> .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
> };
>
> +static int __init efi_remap_init(void)
> +{
> + u64 mapsize;
> +
> + pr_info("Remapping and enabling EFI services.\n");
> +
> + mapsize = memmap.map_end - memmap.map;
> + memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
> + mapsize);
> + if (!memmap.map) {
> + pr_err("Failed to remap EFI memory map\n");
> + return -ENOMEM;
> + }
> + memmap.map_end = memmap.map + mapsize;
> + efi.memmap = &memmap;
> +
> + efi.systab = (__force void *)ioremap_cache(efi_system_table,
> + sizeof(efi_system_table_t));
> + if (!efi.systab) {

Is there a reason why memmap.map isn't iounmap() in the error path?
The original code didn't have it either, hence the question.

Thanks,
Mathieu

> + pr_err("Failed to remap EFI System Table\n");
> + return -ENOMEM;
> + }
> + set_bit(EFI_SYSTEM_TABLES, &efi.flags);
> +
> + return 0;
> +}
> +
> static bool __init efi_virtmap_init(void)
> {
> efi_memory_desc_t *md;
> @@ -75,7 +103,7 @@ static bool __init efi_virtmap_init(void)
> */
> static int __init arm_enable_runtime_services(void)
> {
> - u64 mapsize;
> + int ret;
>
> if (!efi_enabled(EFI_BOOT)) {
> pr_info("EFI services will not be available.\n");
> @@ -87,25 +115,14 @@ static int __init arm_enable_runtime_services(void)
> return 0;
> }
>
> - pr_info("Remapping and enabling EFI services.\n");
> -
> - mapsize = memmap.map_end - memmap.map;
> - memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
> - mapsize);
> - if (!memmap.map) {
> - pr_err("Failed to remap EFI memory map\n");
> - return -ENOMEM;
> + if (efi_enabled(EFI_RUNTIME_SERVICES)) {
> + pr_info("EFI runtime services access via paravirt.\n");
> + return 0;
> }
> - memmap.map_end = memmap.map + mapsize;
> - efi.memmap = &memmap;
>
> - efi.systab = (__force void *)ioremap_cache(efi_system_table,
> - sizeof(efi_system_table_t));
> - if (!efi.systab) {
> - pr_err("Failed to remap EFI System Table\n");
> - return -ENOMEM;
> - }
> - set_bit(EFI_SYSTEM_TABLES, &efi.flags);
> + ret = efi_remap_init();
> + if (ret)
> + return ret;
>
> if (!efi_virtmap_init()) {
> pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
> @@ -122,6 +139,23 @@ static int __init arm_enable_runtime_services(void)
> }
> early_initcall(arm_enable_runtime_services);
>
> +int __init xen_arm_enable_runtime_services(void)
> +{
> + int ret;
> +
> + ret = efi_remap_init();
> + if (ret)
> + return ret;
> +
> + if (IS_ENABLED(CONFIG_XEN_EFI)) {
> + /* Set up runtime services function pointers for Xen Dom0 */
> + xen_efi_runtime_setup();
> + efi.runtime_version = efi.systab->hdr.revision;
> + }
> +
> + return 0;
> +}
> +
> void efi_virtmap_load(void)
> {
> preempt_disable();
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index 3a69ed5..f586e1e 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -469,12 +469,14 @@ device_initcall(efi_load_efivars);
> FIELD_SIZEOF(struct efi_fdt_params, field) \
> }
>
> -static __initdata struct {
> +struct params {
> const char name[32];
> const char propname[32];
> int offset;
> int size;
> -} dt_params[] = {
> +};
> +
> +static __initdata struct params fdt_params[] = {
> UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
> UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
> UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
> @@ -482,44 +484,91 @@ static __initdata struct {
> UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
> };
>
> +static __initdata struct params xen_fdt_params[] = {
> + UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
> + UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
> + UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
> + UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
> + UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
> +};
> +
> +#define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params)
> +
> +static __initdata struct {
> + const char *uname;
> + const char *subnode;
> + struct params *params;
> +} dt_params[] = {
> + { "hypervisor", "uefi", xen_fdt_params },
> + { "chosen", NULL, fdt_params },
> +};
> +
> struct param_info {
> int found;
> void *params;
> + const char *missing;
> };
>
> -static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
> - int depth, void *data)
> +static int __init __find_uefi_params(unsigned long node,
> + struct param_info *info,
> + struct params *params)
> {
> - struct param_info *info = data;
> const void *prop;
> void *dest;
> u64 val;
> int i, len;
>
> - if (depth != 1 || strcmp(uname, "chosen") != 0)
> - return 0;
> -
> - for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
> - prop = of_get_flat_dt_prop(node, dt_params[i].propname, &len);
> - if (!prop)
> + for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
> + prop = of_get_flat_dt_prop(node, params[i].propname, &len);
> + if (!prop) {
> + info->missing = params[i].name;
> return 0;
> - dest = info->params + dt_params[i].offset;
> + }
> +
> + dest = info->params + params[i].offset;
> info->found++;
>
> val = of_read_number(prop, len / sizeof(u32));
>
> - if (dt_params[i].size == sizeof(u32))
> + if (params[i].size == sizeof(u32))
> *(u32 *)dest = val;
> else
> *(u64 *)dest = val;
>
> if (efi_enabled(EFI_DBG))
> - pr_info(" %s: 0x%0*llx\n", dt_params[i].name,
> - dt_params[i].size * 2, val);
> + pr_info(" %s: 0x%0*llx\n", params[i].name,
> + params[i].size * 2, val);
> }
> +
> return 1;
> }
>
> +static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
> + int depth, void *data)
> +{
> + struct param_info *info = data;
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
> + const char *subnode = dt_params[i].subnode;
> +
> + if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
> + info->missing = dt_params[i].params[0].name;
> + continue;
> + }
> +
> + if (subnode) {
> + node = of_get_flat_dt_subnode_by_name(node, subnode);
> + if (node < 0)
> + return 0;
> + }
> +
> + return __find_uefi_params(node, info, dt_params[i].params);
> + }
> +
> + return 0;
> +}
> +
> int __init efi_get_fdt_params(struct efi_fdt_params *params)
> {
> struct param_info info;
> @@ -535,7 +584,7 @@ int __init efi_get_fdt_params(struct efi_fdt_params *params)
> pr_info("UEFI not found.\n");
> else if (!ret)
> pr_err("Can't find '%s' in device tree!\n",
> - dt_params[info.found].name);
> + info.missing);
>
> return ret;
> }
> --
> 2.0.4
>
>
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Next message: Jani Nikula: "Re: Kernel docs: muddying the waters a bit"
Previous message: R, Vignesh: "Re: [PATCH] Input: ti_am335x_tsc - Mark IRQ as wakeup capable"
In reply to: Shannon Zhao: "[PATCH] Xen: EFI: Parse DT parameters for Xen specific UEFI"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]