diff options
| -rw-r--r-- | arch/arm/mach-imx/imx8/fdt.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/imx8/fdt.c b/arch/arm/mach-imx/imx8/fdt.c index 6d0585f5cc6..ce78c8ce919 100644 --- a/arch/arm/mach-imx/imx8/fdt.c +++ b/arch/arm/mach-imx/imx8/fdt.c @@ -11,6 +11,8 @@ #include <fdt_support.h> #include <linux/libfdt.h> #include <linux/printk.h> +#include <cpu.h> +#include <dm.h> DECLARE_GLOBAL_DATA_PTR; @@ -279,6 +281,134 @@ static int ft_add_optee_node(void *fdt, struct bd_info *bd) return 0; } +static int delete_node(void *blob, const char *node) +{ + int nodeoffset; + int err; + + nodeoffset = fdt_path_offset(blob, node); + if (nodeoffset < 0) + return -ENXIO; + + err = fdt_del_node(blob, nodeoffset); + if (err) + return -EINVAL; + + return 0; +} + +static int change_property(void *blob, const char *node, const char *property, + const void *value, int len) +{ + int nodeoffset; + int err; + + nodeoffset = fdt_path_offset(blob, node); + if (nodeoffset < 0) + return -ENXIO; + + err = fdt_setprop(blob, nodeoffset, property, value, len); + if (err) + return -EINVAL; + + return 0; +} + +static void update_fdt_gpu_industrial_frequencies(void *blob) +{ + u32 gpu_opp_table[6]; + u32 gpu_assigned_clocks[2]; + int err; + + gpu_opp_table[0] = cpu_to_fdt32(625000); /* Normal Core Clock */ + gpu_opp_table[1] = cpu_to_fdt32(0); + gpu_opp_table[2] = cpu_to_fdt32(625000); /* Normal Shader Clock */ + gpu_opp_table[3] = cpu_to_fdt32(0); + gpu_opp_table[4] = cpu_to_fdt32(400000); /* Low Shader and Core Clock */ + gpu_opp_table[5] = cpu_to_fdt32(0); + + gpu_assigned_clocks[0] = cpu_to_fdt32(625000000); /* Core Clock */ + gpu_assigned_clocks[1] = cpu_to_fdt32(625000000); /* Shader Clock */ + + err = change_property(blob, "/bus@53100000/gpu@53100000", + "assigned-clock-rates", gpu_assigned_clocks, + sizeof(gpu_assigned_clocks)); + if (err && err != ENXIO) + printf("Failed to set assigned-clock-rates for GPU0: %s\n", + fdt_strerror(err)); + + err = change_property(blob, "/bus@54100000/gpu@54100000", + "assigned-clock-rates", gpu_assigned_clocks, + sizeof(gpu_assigned_clocks)); + if (err && err != ENXIO) + printf("Failed to set assigned-clock-rates for GPU1: %s\n", + fdt_strerror(err)); + + err = change_property(blob, "/bus@54100000/imx8_gpu1_ss@80000000", + "operating-points", &gpu_opp_table, + sizeof(gpu_opp_table)); + if (err && err != ENXIO) + printf("Failed to set operating-points for GPU: %s\n", + fdt_strerror(err)); +} + +static void update_fdt_cpu_industrial_frequencies(void *blob) +{ + int err; + + err = delete_node(blob, "/opp-table-0/opp-1200000000"); + if (err && err != -ENXIO) + printf("Failed to delete 1.2 GHz node on A53: %s\n", + fdt_strerror(err)); + + err = delete_node(blob, "/opp-table-1/opp-1596000000"); + if (err && err != -ENXIO) + printf("Failed to delete 1.596 GHz node on A72: %s\n", + fdt_strerror(err)); +} + +static void update_fdt_frequencies(void *blob) +{ + struct cpu_info cpu; + struct udevice *dev; + int err; + + uclass_first_device(UCLASS_CPU, &dev); + + err = cpu_get_info(dev, &cpu); + if (err) { + printf("Failed to get CPU info\n"); + return; + } + + /* + * Differentiate between the automotive and industrial variants of the + * i.MX8. The difference of these two CPUs is the maximum frequencies + * for the CPU and GPU. + * Core Automotive [max. MHz] Industrial [max. MHz] + * A53 1200 1104 + * A72 1596 1296 + * GPU Core 800 625 + * GPU Shader 1000 625 + * + * While the SCFW enforces these limits for the CPU, the OS cpufreq + * driver remains unaware, causing a mismatch between reported and + * actual frequencies. This is resolved by removing the unsupprted + * frequencies from the device tree. + * + * The GPU frequencies are not enforced by the SCFW, therefore without + * updating the device tree we overclock the GPU. + * + * Using the cpu_freq variable is the only know way to differentiate + * between the automotive and industrial variants of the i.MX8. + */ + if (cpu.cpu_freq != 1104000000) + return; + + update_fdt_cpu_industrial_frequencies(blob); + update_fdt_gpu_industrial_frequencies(blob); +} + int ft_system_setup(void *blob, struct bd_info *bd) { int ret; @@ -294,6 +424,8 @@ int ft_system_setup(void *blob, struct bd_info *bd) update_fdt_with_owned_resources(blob); + update_fdt_frequencies(blob); + if (is_imx8qm()) { ret = config_smmu_fdt(blob); if (ret) |