[U-Boot] [PATCH v4 0/8] Support Andes RISC-V l2cache on AE350 platform
From: Rick Chen rick@andestech.com
Add a v5l2 cache controller driver that is usually found on Andes RISC-V ae350 platform. It will parse and configure the cache settings (data & instruction prefetch, data & tag latency) from the device tree blob.
Also implement L2 cache flush and disable before jump to linux. The sequence will be preferred as below: L1 flush -> L1 disable -> L2 flush -> L2 disable
Changes in v4: - Remove definitions of v5l2cache.h to cache-v5l2.c
Changes in v3: - Add the enable/disable in sandbox_cache.c. - Parse dtb data in v5l2_ofdata_to_platdata() and configure HW in v5l2_probe(). - Move cache_disable() into dcache_disable() of cache.c
Changes in v2: - Add new patch [1/7] to support dm cache uclass enable and disable ops. - Use ofdata_to_platdata() to parse and save register base instead of global data. - Rename compatible string of "cache" as "v5l2cache". - make v512_init() return void. - Use dm cache uclass api to disable L2 cache.
Rick Chen (8): dm: cache: Add enable and disable ops for cache uclass dm: cache: Add enable and disable ops for sandbox and test dm: cache: add v5l2 cache controller driver riscv: ae350: use the v5l2 driver to configure the cache riscv: ax25: add imply v5l2 cache controller riscv: cache: Flush L2 cache before jump to linux riscv: dts: move out AE350 L2 node from cpus node riscv: cache: use CCTL to flush d-cache
arch/riscv/cpu/ax25/Kconfig | 1 + arch/riscv/cpu/ax25/cache.c | 39 +++++-- arch/riscv/dts/ae350_32.dts | 17 +-- arch/riscv/dts/ae350_64.dts | 17 +-- board/AndesTech/ax25-ae350/ax25-ae350.c | 9 ++ drivers/cache/Kconfig | 9 ++ drivers/cache/Makefile | 1 + drivers/cache/cache-uclass.c | 20 ++++ drivers/cache/cache-v5l2.c | 186 ++++++++++++++++++++++++++++++++ drivers/cache/sandbox_cache.c | 13 +++ include/cache.h | 31 ++++++ test/dm/cache.c | 2 + 12 files changed, 324 insertions(+), 21 deletions(-) create mode 100644 drivers/cache/cache-v5l2.c
From: Rick Chen rick@andestech.com
Add cache enable/disable ops to the DM cache uclass driver
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- drivers/cache/cache-uclass.c | 20 ++++++++++++++++++++ include/cache.h | 31 +++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+)
diff --git a/drivers/cache/cache-uclass.c b/drivers/cache/cache-uclass.c index 97ce024..3b20a10 100644 --- a/drivers/cache/cache-uclass.c +++ b/drivers/cache/cache-uclass.c @@ -17,6 +17,26 @@ int cache_get_info(struct udevice *dev, struct cache_info *info) return ops->get_info(dev, info); }
+int cache_enable(struct udevice *dev) +{ + struct cache_ops *ops = cache_get_ops(dev); + + if (!ops->enable) + return -ENOSYS; + + return ops->enable(dev); +} + +int cache_disable(struct udevice *dev) +{ + struct cache_ops *ops = cache_get_ops(dev); + + if (!ops->disable) + return -ENOSYS; + + return ops->disable(dev); +} + UCLASS_DRIVER(cache) = { .id = UCLASS_CACHE, .name = "cache", diff --git a/include/cache.h b/include/cache.h index c6334ca..32f59fd 100644 --- a/include/cache.h +++ b/include/cache.h @@ -22,6 +22,22 @@ struct cache_ops { * @return 0 if OK, -ve on error */ int (*get_info)(struct udevice *dev, struct cache_info *info); + + /** + * enable() - Enable cache + * + * @dev: Device to check (UCLASS_CACHE) + * @return 0 if OK, -ve on error + */ + int (*enable)(struct udevice *dev); + + /** + * disable() - Flush and disable cache + * + * @dev: Device to check (UCLASS_CACHE) + * @return 0 if OK, -ve on error + */ + int (*disable)(struct udevice *dev); };
#define cache_get_ops(dev) ((struct cache_ops *)(dev)->driver->ops) @@ -35,4 +51,19 @@ struct cache_ops { */ int cache_get_info(struct udevice *dev, struct cache_info *info);
+/** + * cache_enable() - Enable cache + * + * @dev: Device to check (UCLASS_CACHE) + * @return 0 if OK, -ve on error + */ +int cache_enable(struct udevice *dev); + +/** + * cache_disable() - Flush and disable cache + * + * @dev: Device to check (UCLASS_CACHE) + * @return 0 if OK, -ve on error + */ +int cache_disable(struct udevice *dev); #endif
From: Rick Chen rick@andestech.com
Add cache enable and disable ops for test coverage.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- drivers/cache/sandbox_cache.c | 13 +++++++++++++ test/dm/cache.c | 2 ++ 2 files changed, 15 insertions(+)
diff --git a/drivers/cache/sandbox_cache.c b/drivers/cache/sandbox_cache.c index 14cc6b0..9050c4c 100644 --- a/drivers/cache/sandbox_cache.c +++ b/drivers/cache/sandbox_cache.c @@ -17,8 +17,21 @@ static int sandbox_get_info(struct udevice *dev, struct cache_info *info) return 0; }
+static int sandbox_enable(struct udevice *dev) +{ + return 0; +} + +static int snadbox_disable(struct udevice *dev) +{ + return 0; +} + + static const struct cache_ops sandbox_cache_ops = { .get_info = sandbox_get_info, + .enable = sandbox_enable, + .disable = snadbox_disable, };
static const struct udevice_id sandbox_cache_ids[] = { diff --git a/test/dm/cache.c b/test/dm/cache.c index d4144aa..2e244b1 100644 --- a/test/dm/cache.c +++ b/test/dm/cache.c @@ -14,6 +14,8 @@ static int dm_test_reset(struct unit_test_state *uts)
ut_assertok(uclass_get_device(UCLASS_CACHE, 0, &dev_cache)); ut_assertok(cache_get_info(dev, &info)); + ut_assertok(cache_enable(dev)); + ut_assertok(cache_disable(dev));
return 0; }
From: Rick Chen rick@andestech.com
Add a v5l2 cache controller driver that is usually found on Andes RISC-V ae350 platform. It will parse the cache settings from the dtb.
In this version tag and data ram control timing can be adjusted by the requirement from the dtb.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com --- drivers/cache/Kconfig | 9 +++ drivers/cache/Makefile | 1 + drivers/cache/cache-v5l2.c | 186 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 196 insertions(+) create mode 100644 drivers/cache/cache-v5l2.c
diff --git a/drivers/cache/Kconfig b/drivers/cache/Kconfig index 24def7a..629039e 100644 --- a/drivers/cache/Kconfig +++ b/drivers/cache/Kconfig @@ -22,4 +22,13 @@ config L2X0_CACHE ARMv7(32-bit) devices. The driver configures the cache settings found in the device tree.
+config V5L2_CACHE + bool "Andes V5L2 cache driver" + select CACHE + depends on RISCV_NDS_CACHE + help + Support Andes V5L2 cache controller in AE350 platform. + It will configure tag and data ram timing control from the + device tree and enable L2 cache. + endmenu diff --git a/drivers/cache/Makefile b/drivers/cache/Makefile index 9deb961..4a6458c 100644 --- a/drivers/cache/Makefile +++ b/drivers/cache/Makefile @@ -2,3 +2,4 @@ obj-$(CONFIG_CACHE) += cache-uclass.o obj-$(CONFIG_SANDBOX) += sandbox_cache.o obj-$(CONFIG_L2X0_CACHE) += cache-l2x0.o +obj-$(CONFIG_V5L2_CACHE) += cache-v5l2.o diff --git a/drivers/cache/cache-v5l2.c b/drivers/cache/cache-v5l2.c new file mode 100644 index 0000000..d367171 --- /dev/null +++ b/drivers/cache/cache-v5l2.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Andes Technology Corporation + * Rick Chen, Andes Technology Corporation rick@andestech.com + */ + +#include <common.h> +#include <command.h> +#include <cache.h> +#include <dm.h> +#include <asm/io.h> +#include <dm/ofnode.h> + +struct l2cache { + volatile u64 configure; + volatile u64 control; + volatile u64 hpm0; + volatile u64 hpm1; + volatile u64 hpm2; + volatile u64 hpm3; + volatile u64 error_status; + volatile u64 ecc_error; + volatile u64 cctl_command0; + volatile u64 cctl_access_line0; + volatile u64 cctl_command1; + volatile u64 cctl_access_line1; + volatile u64 cctl_command2; + volatile u64 cctl_access_line2; + volatile u64 cctl_command3; + volatile u64 cctl_access_line4; + volatile u64 cctl_status; +}; + +/* Control Register */ +#define L2_ENABLE 0x1 +/* prefetch */ +#define IPREPETCH_OFF 3 +#define DPREPETCH_OFF 5 +#define IPREPETCH_MSK (3 << IPREPETCH_OFF) +#define DPREPETCH_MSK (3 << DPREPETCH_OFF) +/* tag ram */ +#define TRAMOCTL_OFF 8 +#define TRAMICTL_OFF 10 +#define TRAMOCTL_MSK (3 << TRAMOCTL_OFF) +#define TRAMICTL_MSK BIT(TRAMICTL_OFF) +/* data ram */ +#define DRAMOCTL_OFF 11 +#define DRAMICTL_OFF 13 +#define DRAMOCTL_MSK (3 << DRAMOCTL_OFF) +#define DRAMICTL_MSK BIT(DRAMICTL_OFF) + +/* CCTL Command Register */ +#define CCTL_CMD_REG(base, hart) ((ulong)(base) + 0x40 + (hart) * 0x10) +#define L2_WBINVAL_ALL 0x12 + +/* CCTL Status Register */ +#define CCTL_STATUS_MSK(hart) (0xf << ((hart) * 4)) +#define CCTL_STATUS_IDLE(hart) (0 << ((hart) * 4)) +#define CCTL_STATUS_PROCESS(hart) (1 << ((hart) * 4)) +#define CCTL_STATUS_ILLEGAL(hart) (2 << ((hart) * 4)) + +DECLARE_GLOBAL_DATA_PTR; + +struct v5l2_plat { + struct l2cache *regs; + u32 iprefetch; + u32 dprefetch; + u32 tram_ctl[2]; + u32 dram_ctl[2]; +}; + +static int v5l2_enable(struct udevice *dev) +{ + struct v5l2_plat *plat = dev_get_platdata(dev); + volatile struct l2cache *regs = plat->regs; + + if (regs) + setbits_le32(®s->control, L2_ENABLE); + + return 0; +} + +static int v5l2_disable(struct udevice *dev) +{ + struct v5l2_plat *plat = dev_get_platdata(dev); + volatile struct l2cache *regs = plat->regs; + u8 hart = gd->arch.boot_hart; + void __iomem *cctlcmd = (void __iomem *)CCTL_CMD_REG(regs, hart); + + if ((regs) && (readl(®s->control) & L2_ENABLE)) { + writel(L2_WBINVAL_ALL, cctlcmd); + + while ((readl(®s->cctl_status) & CCTL_STATUS_MSK(hart))) { + if ((readl(®s->cctl_status) & CCTL_STATUS_ILLEGAL(hart))) { + printf("L2 flush illegal! hanging..."); + hang(); + } + } + clrbits_le32(®s->control, L2_ENABLE); + } + + return 0; +} + +static int v5l2_ofdata_to_platdata(struct udevice *dev) +{ + struct v5l2_plat *plat = dev_get_platdata(dev); + struct l2cache *regs; + + regs = (struct l2cache *)dev_read_addr(dev); + plat->regs = regs; + + plat->iprefetch = -EINVAL; + plat->dprefetch = -EINVAL; + plat->tram_ctl[0] = -EINVAL; + plat->dram_ctl[0] = -EINVAL; + + /* Instruction and data fetch prefetch depth */ + dev_read_u32(dev, "andes,inst-prefetch", &plat->iprefetch); + dev_read_u32(dev, "andes,data-prefetch", &plat->dprefetch); + + /* Set tag RAM and data RAM setup and output cycle */ + dev_read_u32_array(dev, "andes,tag-ram-ctl", plat->tram_ctl, 2); + dev_read_u32_array(dev, "andes,data-ram-ctl", plat->dram_ctl, 2); + + return 0; +} + +static int v5l2_probe(struct udevice *dev) +{ + struct v5l2_plat *plat = dev_get_platdata(dev); + struct l2cache *regs = plat->regs; + u32 ctl_val; + + ctl_val = readl(®s->control); + + if (!(ctl_val & L2_ENABLE)) + ctl_val |= L2_ENABLE; + + if (plat->iprefetch != -EINVAL) { + ctl_val &= ~(IPREPETCH_MSK); + ctl_val |= (plat->iprefetch << IPREPETCH_OFF); + } + + if (plat->dprefetch != -EINVAL) { + ctl_val &= ~(DPREPETCH_MSK); + ctl_val |= (plat->dprefetch << DPREPETCH_OFF); + } + + if (plat->tram_ctl[0] != -EINVAL) { + ctl_val &= ~(TRAMOCTL_MSK | TRAMICTL_MSK); + ctl_val |= plat->tram_ctl[0] << TRAMOCTL_OFF; + ctl_val |= plat->tram_ctl[1] << TRAMICTL_OFF; + } + + if (plat->dram_ctl[0] != -EINVAL) { + ctl_val &= ~(DRAMOCTL_MSK | DRAMICTL_MSK); + ctl_val |= plat->dram_ctl[0] << DRAMOCTL_OFF; + ctl_val |= plat->dram_ctl[1] << DRAMICTL_OFF; + } + + writel(ctl_val, ®s->control); + + return 0; +} + +static const struct udevice_id v5l2_cache_ids[] = { + { .compatible = "v5l2cache" }, + {} +}; + +static const struct cache_ops v5l2_cache_ops = { + .enable = v5l2_enable, + .disable = v5l2_disable, +}; + +U_BOOT_DRIVER(v5l2_cache) = { + .name = "v5l2_cache", + .id = UCLASS_CACHE, + .of_match = v5l2_cache_ids, + .ofdata_to_platdata = v5l2_ofdata_to_platdata, + .probe = v5l2_probe, + .platdata_auto_alloc_size = sizeof(struct v5l2_plat), + .ops = &v5l2_cache_ops, + .flags = DM_FLAG_PRE_RELOC, +};
On Wed, Aug 28, 2019 at 6:52 PM Andes uboot@andestech.com wrote:
From: Rick Chen rick@andestech.com
Add a v5l2 cache controller driver that is usually found on Andes RISC-V ae350 platform. It will parse the cache settings from the dtb.
In this version tag and data ram control timing can be adjusted by the requirement from the dtb.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com
drivers/cache/Kconfig | 9 +++ drivers/cache/Makefile | 1 + drivers/cache/cache-v5l2.c | 186 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 196 insertions(+) create mode 100644 drivers/cache/cache-v5l2.c
Reviewed-by: Bin Meng bmeng.cn@gmail.com
From: Rick Chen rick@andestech.com
Find the UCLASS_CACHE driver to configure the cache controller's settings.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- board/AndesTech/ax25-ae350/ax25-ae350.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/board/AndesTech/ax25-ae350/ax25-ae350.c b/board/AndesTech/ax25-ae350/ax25-ae350.c index 3d65ce7..b43eebb 100644 --- a/board/AndesTech/ax25-ae350/ax25-ae350.c +++ b/board/AndesTech/ax25-ae350/ax25-ae350.c @@ -11,6 +11,7 @@ #include <linux/io.h> #include <faraday/ftsmc020.h> #include <fdtdec.h> +#include <dm.h>
DECLARE_GLOBAL_DATA_PTR;
@@ -93,10 +94,18 @@ int smc_init(void) return 0; }
+static void v5l2_init(void) +{ + struct udevice *dev; + + uclass_get_device(UCLASS_CACHE, 0, &dev); +} + #ifdef CONFIG_BOARD_EARLY_INIT_F int board_early_init_f(void) { smc_init(); + v5l2_init();
return 0; }
From: Rick Chen rick@andestech.com
Select the v5l2 UCLASS_CACHE driver for ax25.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- arch/riscv/cpu/ax25/Kconfig | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/riscv/cpu/ax25/Kconfig b/arch/riscv/cpu/ax25/Kconfig index 6b4b92e..49be775 100644 --- a/arch/riscv/cpu/ax25/Kconfig +++ b/arch/riscv/cpu/ax25/Kconfig @@ -4,6 +4,7 @@ config RISCV_NDS imply CPU imply CPU_RISCV imply RISCV_TIMER + imply V5L2_CACHE imply ANDES_PLIC if RISCV_MMODE imply ANDES_PLMT if RISCV_MMODE help
From: Rick Chen rick@andestech.com
Flush and disable L2 cache in dcache_disable() which will be called in cleanup_before_linux() before jump to linux.
The sequence will be preferred as below: L1 flush -> L1 disable -> L2 flush -> L2 disable
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- arch/riscv/cpu/ax25/cache.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)
diff --git a/arch/riscv/cpu/ax25/cache.c b/arch/riscv/cpu/ax25/cache.c index cd95058..8f5455e 100644 --- a/arch/riscv/cpu/ax25/cache.c +++ b/arch/riscv/cpu/ax25/cache.c @@ -5,6 +5,9 @@ */
#include <common.h> +#include <dm.h> +#include <dm/uclass-internal.h> +#include <cache.h>
void flush_dcache_all(void) { @@ -59,11 +62,18 @@ void dcache_enable(void) { #if !CONFIG_IS_ENABLED(SYS_DCACHE_OFF) #ifdef CONFIG_RISCV_NDS_CACHE + struct udevice *dev = NULL; + asm volatile ( "csrr t1, mcache_ctl\n\t" "ori t0, t1, 0x2\n\t" "csrw mcache_ctl, t0\n\t" ); + + uclass_find_first_device(UCLASS_CACHE, &dev); + + if (dev) + cache_enable(dev); #endif #endif } @@ -72,12 +82,19 @@ void dcache_disable(void) { #if !CONFIG_IS_ENABLED(SYS_DCACHE_OFF) #ifdef CONFIG_RISCV_NDS_CACHE + struct udevice *dev = NULL; + asm volatile ( "fence\n\t" "csrr t1, mcache_ctl\n\t" "andi t0, t1, ~0x2\n\t" "csrw mcache_ctl, t0\n\t" ); + + uclass_find_first_device(UCLASS_CACHE, &dev); + + if (dev) + cache_disable(dev); #endif #endif }
From: Rick Chen rick@andestech.com
When L2 node exists inside cpus node, uclass_get_device can not parse L2 node successfully. So move it outside from cpus node.
Also add tag-ram-ctl and data-ram-ctl attributes for v5l2 cache controller driver. This can adjust timing by requirement from dtb to improve performance.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- arch/riscv/dts/ae350_32.dts | 17 +++++++++++------ arch/riscv/dts/ae350_64.dts | 17 +++++++++++------ 2 files changed, 22 insertions(+), 12 deletions(-)
diff --git a/arch/riscv/dts/ae350_32.dts b/arch/riscv/dts/ae350_32.dts index cb6ee13..97b7cee 100644 --- a/arch/riscv/dts/ae350_32.dts +++ b/arch/riscv/dts/ae350_32.dts @@ -62,13 +62,18 @@ compatible = "riscv,cpu-intc"; }; }; + };
- L2: l2-cache@e0500000 { - compatible = "cache"; - cache-level = <2>; - cache-size = <0x40000>; - reg = <0x0 0xe0500000 0x0 0x40000>; - }; + L2: l2-cache@e0500000 { + compatible = "v5l2cache"; + cache-level = <2>; + cache-size = <0x40000>; + reg = <0xe0500000 0x40000>; + andes,inst-prefetch = <3>; + andes,data-prefetch = <3>; + /* The value format is <XRAMOCTL XRAMICTL> */ + andes,tag-ram-ctl = <0 0>; + andes,data-ram-ctl = <0 0>; };
memory@0 { diff --git a/arch/riscv/dts/ae350_64.dts b/arch/riscv/dts/ae350_64.dts index 705491a..d8f00f8 100644 --- a/arch/riscv/dts/ae350_64.dts +++ b/arch/riscv/dts/ae350_64.dts @@ -62,13 +62,18 @@ compatible = "riscv,cpu-intc"; }; }; + };
- L2: l2-cache@e0500000 { - compatible = "cache"; - cache-level = <2>; - cache-size = <0x40000>; - reg = <0x0 0xe0500000 0x0 0x40000>; - }; + L2: l2-cache@e0500000 { + compatible = "v5l2cache"; + cache-level = <2>; + cache-size = <0x40000>; + reg = <0x0 0xe0500000 0x0 0x40000>; + andes,inst-prefetch = <3>; + andes,data-prefetch = <3>; + /* The value format is <XRAMOCTL XRAMICTL> */ + andes,tag-ram-ctl = <0 0>; + andes,data-ram-ctl = <0 0>; };
memory@0 {
From: Rick Chen rick@andestech.com
Use CCTL command to do d-cache write back and invalidate instead of fence.
Signed-off-by: Rick Chen rick@andestech.com Cc: KC Lin kclin@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- arch/riscv/cpu/ax25/cache.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-)
diff --git a/arch/riscv/cpu/ax25/cache.c b/arch/riscv/cpu/ax25/cache.c index 8f5455e..41de30c 100644 --- a/arch/riscv/cpu/ax25/cache.c +++ b/arch/riscv/cpu/ax25/cache.c @@ -8,17 +8,21 @@ #include <dm.h> #include <dm/uclass-internal.h> #include <cache.h> +#include <asm/csr.h> + +#ifdef CONFIG_RISCV_NDS_CACHE +/* mcctlcommand */ +#define CCTL_REG_MCCTLCOMMAND_NUM 0x7cc + +/* D-cache operation */ +#define CCTL_L1D_WBINVAL_ALL 6 +#endif
void flush_dcache_all(void) { - /* - * Andes' AX25 does not have a coherence agent. U-Boot must use data - * cache flush and invalidate functions to keep data in the system - * coherent. - * The implementation of the fence instruction in the AX25 flushes the - * data cache and is used for this purpose. - */ - asm volatile ("fence" ::: "memory"); +#ifdef CONFIG_RISCV_NDS_CACHE + csr_write(CCTL_REG_MCCTLCOMMAND_NUM, CCTL_L1D_WBINVAL_ALL); +#endif }
void flush_dcache_range(unsigned long start, unsigned long end) @@ -84,8 +88,8 @@ void dcache_disable(void) #ifdef CONFIG_RISCV_NDS_CACHE struct udevice *dev = NULL;
+ csr_write(CCTL_REG_MCCTLCOMMAND_NUM, CCTL_L1D_WBINVAL_ALL); asm volatile ( - "fence\n\t" "csrr t1, mcache_ctl\n\t" "andi t0, t1, ~0x2\n\t" "csrw mcache_ctl, t0\n\t"
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