From mboxrd@z Thu Jan 1 00:00:00 1970 From: Atish Patra Date: Fri, 13 Mar 2020 17:54:40 -0700 Subject: [PATCH v2 3/4] riscv: Provide a mechanism for riscv boards to parse reserved memory In-Reply-To: <20200314001132.17393-4-atish.patra@wdc.com> References: <20200314001132.17393-1-atish.patra@wdc.com> <20200314001132.17393-4-atish.patra@wdc.com> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Fri, Mar 13, 2020 at 5:12 PM Atish Patra wrote: > > In RISC-V, M-mode software can reserve physical memory regions > by setting appropriate physical memory protection (PMP) csr. As the > PMP csr are accessible only in M-mode, S-mode U-Boot can not read > this configuration directly. However, M-mode software can pass this > information via reserved-memory node in device tree so that S-mode > software can access this information. > > In U-boot, any board may use the DT in following ways. > 1. OF_SEPARTE: It ignores the DT from previous stage and uses the DT > from U-Boot sources. > 2. OF_PRIOR_STATE: It reuses the DT from previous stage. > For case 1: U-Boot needs to parse the reserved-memory node from the > DT passed from the previous stage and update the DT in use. > > This patch provides a framework to do that from any RISC-V boards. > > Signed-off-by: Atish Patra > --- > arch/riscv/cpu/start.S | 1 + > arch/riscv/include/asm/global_data.h | 1 + > arch/riscv/include/asm/u-boot-riscv.h | 1 + > arch/riscv/lib/asm-offsets.c | 1 + > arch/riscv/lib/bootm.c | 37 +++++++++++++++++++++++++++ > 5 files changed, 41 insertions(+) > > diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S > index 6b3ff99c3882..0282685c2906 100644 > --- a/arch/riscv/cpu/start.S > +++ b/arch/riscv/cpu/start.S > @@ -121,6 +121,7 @@ call_board_init_f_0: > > jal board_init_f_init_reserve > > + SREG s1, GD_FIRMWARE_FDT_ADDR(gp) > /* save the boot hart id to global_data */ > SREG tp, GD_BOOT_HART(gp) > > diff --git a/arch/riscv/include/asm/global_data.h b/arch/riscv/include/asm/global_data.h > index b74bd7e738bb..51ac8d1c98e2 100644 > --- a/arch/riscv/include/asm/global_data.h > +++ b/arch/riscv/include/asm/global_data.h > @@ -15,6 +15,7 @@ > /* Architecture-specific global data */ > struct arch_global_data { > long boot_hart; /* boot hart id */ > + phys_addr_t firmware_fdt_addr; > #ifdef CONFIG_SIFIVE_CLINT > void __iomem *clint; /* clint base address */ > #endif > diff --git a/arch/riscv/include/asm/u-boot-riscv.h b/arch/riscv/include/asm/u-boot-riscv.h > index 49febd588102..b7bea0ba184d 100644 > --- a/arch/riscv/include/asm/u-boot-riscv.h > +++ b/arch/riscv/include/asm/u-boot-riscv.h > @@ -17,5 +17,6 @@ int cleanup_before_linux(void); > /* board/.../... */ > int board_init(void); > void board_quiesce_devices(void); > +int riscv_board_reserved_mem_fixup(void *fdt); > > #endif /* _U_BOOT_RISCV_H_ */ > diff --git a/arch/riscv/lib/asm-offsets.c b/arch/riscv/lib/asm-offsets.c > index 4fa4fd371473..7301c1b98e23 100644 > --- a/arch/riscv/lib/asm-offsets.c > +++ b/arch/riscv/lib/asm-offsets.c > @@ -14,6 +14,7 @@ > int main(void) > { > DEFINE(GD_BOOT_HART, offsetof(gd_t, arch.boot_hart)); > + DEFINE(GD_FIRMWARE_FDT_ADDR, offsetof(gd_t, arch.firmware_fdt_addr)); > #ifndef CONFIG_XIP > DEFINE(GD_AVAILABLE_HARTS, offsetof(gd_t, arch.available_harts)); > #endif > diff --git a/arch/riscv/lib/bootm.c b/arch/riscv/lib/bootm.c > index f927694ae32f..3a4d0bf14c86 100644 > --- a/arch/riscv/lib/bootm.c > +++ b/arch/riscv/lib/bootm.c > @@ -19,6 +19,7 @@ > #include > #include > #include > +#include > > DECLARE_GLOBAL_DATA_PTR; > > @@ -26,6 +27,42 @@ __weak void board_quiesce_devices(void) > { > } > > +int riscv_board_reserved_mem_fixup(void *fdt) > +{ > + uint32_t phandle; > + struct fdt_memory pmp_mem; > + int err; > + void *src_fdt_addr; > + int offset, node; > + phys_addr_t addr, size; > + > + src_fdt_addr = map_sysmem(gd->arch.firmware_fdt_addr, 0); > + offset = fdt_path_offset(src_fdt_addr, "/reserved-memory"); > + if (offset < 0) { > + printf("No reserved memory region found in FDT\n"); > + return offset; > + } > + > + fdt_for_each_subnode(node, src_fdt_addr, offset) { > + const char *name = fdt_get_name(src_fdt_addr, node, NULL); > + > + addr = fdtdec_get_addr_size(src_fdt_addr, node, "reg", &size); > + if (addr == FDT_ADDR_T_NONE) { > + debug("failed to read address/size for %s\n", name); > + continue; > + } > + pmp_mem.start = addr; > + pmp_mem.end = addr + size; > + err = fdtdec_add_reserved_memory(fdt, name, &pmp_mem, &phandle); > + if (err < 0) { > + printf("failed to add reserved memory: %d\n", err); > + return err; > + } > + } > + > + return 0; > +} > + > int arch_fixup_fdt(void *blob) > { > u32 size; > -- > 2.25.1 > Fixed palmer's email address. Sorry for the spam. -- Regards, Atish