diff options
| -rw-r--r-- | include/sbi_utils/fdt/fdt_fixup.h | 14 | ||||
| -rw-r--r-- | lib/utils/fdt/fdt_fixup.c | 49 | ||||
| -rw-r--r-- | platform/generic/include/platform_override.h | 1 | ||||
| -rw-r--r-- | platform/generic/platform.c | 6 | ||||
| -rw-r--r-- | platform/generic/sifive_fu540.c | 14 | ||||
| -rw-r--r-- | platform/sifive/fu540/platform.c | 7 |
6 files changed, 80 insertions, 11 deletions
diff --git a/include/sbi_utils/fdt/fdt_fixup.h b/include/sbi_utils/fdt/fdt_fixup.h index 54568c2..0697a18 100644 --- a/include/sbi_utils/fdt/fdt_fixup.h +++ b/include/sbi_utils/fdt/fdt_fixup.h @@ -48,6 +48,20 @@ void fdt_plic_fixup(void *fdt, const char *compat); int fdt_reserved_memory_fixup(void *fdt); /** + * Fix up the reserved memory subnodes in the device tree + * + * This routine adds the no-map property to the reserved memory subnodes so + * that the OS does not map those PMP protected memory regions. + * + * Platform codes must call this helper in their final_init() after fdt_fixups() + * if the OS should not map the PMP protected reserved regions. + * + * @param fdt: device tree blob + * @return zero on success and -ve on failure + */ +int fdt_reserved_memory_nomap_fixup(void *fdt); + +/** * General device tree fix-up * * This routine do all required device tree fix-ups for a typical platform. diff --git a/lib/utils/fdt/fdt_fixup.c b/lib/utils/fdt/fdt_fixup.c index 49848b2..adf1be3 100644 --- a/lib/utils/fdt/fdt_fixup.c +++ b/lib/utils/fdt/fdt_fixup.c @@ -70,7 +70,7 @@ void fdt_plic_fixup(void *fdt, const char *compat) static int fdt_resv_memory_update_node(void *fdt, unsigned long addr, unsigned long size, int index, - int parent) + int parent, bool no_map) { int na = fdt_address_cells(fdt, 0); int ns = fdt_size_cells(fdt, 0); @@ -99,14 +99,16 @@ static int fdt_resv_memory_update_node(void *fdt, unsigned long addr, if (subnode < 0) return subnode; - /* - * Tell operating system not to create a virtual - * mapping of the region as part of its standard - * mapping of system memory. - */ - err = fdt_setprop_empty(fdt, subnode, "no-map"); - if (err < 0) - return err; + if (no_map) { + /* + * Tell operating system not to create a virtual + * mapping of the region as part of its standard + * mapping of system memory. + */ + err = fdt_setprop_empty(fdt, subnode, "no-map"); + if (err < 0) + return err; + } /* encode the <reg> property value */ val = reg; @@ -199,7 +201,8 @@ int fdt_reserved_memory_fixup(void *fdt) */ addr = scratch->fw_start & ~(scratch->fw_size - 1UL); size = (1UL << log2roundup(scratch->fw_size)); - return fdt_resv_memory_update_node(fdt, addr, size, 0, parent); + return fdt_resv_memory_update_node(fdt, addr, size, + 0, parent, true); } for (i = 0, j = 0; i < sbi_hart_pmp_count(scratch); i++) { @@ -211,13 +214,37 @@ int fdt_reserved_memory_fixup(void *fdt) if (prot & (PMP_R | PMP_W | PMP_X)) continue; - fdt_resv_memory_update_node(fdt, addr, size, j, parent); + fdt_resv_memory_update_node(fdt, addr, size, j, parent, false); j++; } return 0; } +int fdt_reserved_memory_nomap_fixup(void *fdt) +{ + int parent, subnode; + int err; + + /* Locate the reserved memory node */ + parent = fdt_path_offset(fdt, "/reserved-memory"); + if (parent < 0) + return parent; + + fdt_for_each_subnode(subnode, fdt, parent) { + /* + * Tell operating system not to create a virtual + * mapping of the region as part of its standard + * mapping of system memory. + */ + err = fdt_setprop_empty(fdt, subnode, "no-map"); + if (err < 0) + return err; + } + + return 0; +} + void fdt_fixups(void *fdt) { fdt_plic_fixup(fdt, "riscv,plic0"); diff --git a/platform/generic/include/platform_override.h b/platform/generic/include/platform_override.h index 1262627..8a53cdf 100644 --- a/platform/generic/include/platform_override.h +++ b/platform/generic/include/platform_override.h @@ -21,6 +21,7 @@ struct platform_override { void (*early_exit)(const struct fdt_match *match); void (*final_exit)(const struct fdt_match *match); int (*system_reset)(u32 reset_type, const struct fdt_match *match); + int (*fdt_fixup)(void *fdt, const struct fdt_match *match); }; #endif diff --git a/platform/generic/platform.c b/platform/generic/platform.c index 57058ff..c3cf423 100644 --- a/platform/generic/platform.c +++ b/platform/generic/platform.c @@ -153,6 +153,12 @@ static int generic_final_init(bool cold_boot) fdt_cpu_fixup(fdt); fdt_fixups(fdt); + if (generic_plat && generic_plat->fdt_fixup) { + rc = generic_plat->fdt_fixup(fdt, generic_plat_match); + if (rc) + return rc; + } + return 0; } diff --git a/platform/generic/sifive_fu540.c b/platform/generic/sifive_fu540.c index 9ddafa0..08f7bfc 100644 --- a/platform/generic/sifive_fu540.c +++ b/platform/generic/sifive_fu540.c @@ -9,6 +9,7 @@ #include <platform_override.h> #include <sbi_utils/fdt/fdt_helper.h> +#include <sbi_utils/fdt/fdt_fixup.h> static u64 sifive_fu540_tlbr_flush_limit(const struct fdt_match *match) { @@ -19,6 +20,18 @@ static u64 sifive_fu540_tlbr_flush_limit(const struct fdt_match *match) return 0; } +static int sifive_fu540_fdt_fixup(void *fdt, const struct fdt_match *match) +{ + /* + * SiFive Freedom U540 has an erratum that prevents S-mode software + * to access a PMP protected region using 1GB page table mapping, so + * always add the no-map attribute on this platform. + */ + fdt_reserved_memory_nomap_fixup(fdt); + + return 0; +} + static const struct fdt_match sifive_fu540_match[] = { { .compatible = "sifive,fu540" }, { .compatible = "sifive,fu540g" }, @@ -30,4 +43,5 @@ static const struct fdt_match sifive_fu540_match[] = { const struct platform_override sifive_fu540 = { .match_table = sifive_fu540_match, .tlbr_flush_limit = sifive_fu540_tlbr_flush_limit, + .fdt_fixup = sifive_fu540_fdt_fixup, }; diff --git a/platform/sifive/fu540/platform.c b/platform/sifive/fu540/platform.c index 48d887f..755e479 100644 --- a/platform/sifive/fu540/platform.c +++ b/platform/sifive/fu540/platform.c @@ -63,6 +63,13 @@ static void fu540_modify_dt(void *fdt) fdt_cpu_fixup(fdt); fdt_fixups(fdt); + + /* + * SiFive Freedom U540 has an erratum that prevents S-mode software + * to access a PMP protected region using 1GB page table mapping, so + * always add the no-map attribute on this platform. + */ + fdt_reserved_memory_nomap_fixup(fdt); } static int fu540_final_init(bool cold_boot) |