diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/platform/x86/dcdbas.c | 43 |
1 files changed, 30 insertions, 13 deletions
diff --git a/drivers/platform/x86/dcdbas.c b/drivers/platform/x86/dcdbas.c index 84f4cc839cc3..d513a59a5d47 100644 --- a/drivers/platform/x86/dcdbas.c +++ b/drivers/platform/x86/dcdbas.c @@ -15,6 +15,7 @@ #include <linux/platform_device.h> #include <linux/acpi.h> #include <linux/dma-mapping.h> +#include <linux/dmi.h> #include <linux/errno.h> #include <linux/cpu.h> #include <linux/gfp.h> @@ -34,7 +35,7 @@ #include "dcdbas.h" #define DRIVER_NAME "dcdbas" -#define DRIVER_VERSION "5.6.0-3.3" +#define DRIVER_VERSION "5.6.0-3.4" #define DRIVER_DESCRIPTION "Dell Systems Management Base Driver" static struct platform_device *dcdbas_pdev; @@ -45,7 +46,7 @@ static unsigned long smi_data_buf_size; static unsigned long max_smi_data_buf_size = MAX_SMI_DATA_BUF_SIZE; static u32 smi_data_buf_phys_addr; static DEFINE_MUTEX(smi_data_lock); -static u8 *eps_buffer; +static u8 *bios_buffer; static unsigned int host_control_action; static unsigned int host_control_smi_type; @@ -518,8 +519,10 @@ static inline struct smm_eps_table *check_eps_table(u8 *addr) static int dcdbas_check_wsmt(void) { + const struct dmi_device *dev = NULL; struct acpi_table_wsmt *wsmt = NULL; struct smm_eps_table *eps = NULL; + u64 bios_buf_paddr; u64 remap_size; u8 *addr; @@ -532,6 +535,17 @@ static int dcdbas_check_wsmt(void) !(wsmt->protection_flags & ACPI_WSMT_COMM_BUFFER_NESTED_PTR_PROTECTION)) return 0; + /* + * BIOS could provide the address/size of the protected buffer + * in an SMBIOS string or in an EPS structure in 0xFxxxx. + */ + + /* Check SMBIOS for buffer address */ + while ((dev = dmi_find_device(DMI_DEV_TYPE_OEM_STRING, NULL, dev))) + if (sscanf(dev->name, "30[%16llx;%8llx]", &bios_buf_paddr, + &remap_size) == 2) + goto remap; + /* Scan for EPS (entry point structure) */ for (addr = (u8 *)__va(0xf0000); addr < (u8 *)__va(0x100000 - sizeof(struct smm_eps_table)); @@ -542,34 +556,37 @@ static int dcdbas_check_wsmt(void) } if (!eps) { - dev_dbg(&dcdbas_pdev->dev, "found WSMT, but no EPS found\n"); + dev_dbg(&dcdbas_pdev->dev, "found WSMT, but no firmware buffer found\n"); return -ENODEV; } + bios_buf_paddr = eps->smm_comm_buff_addr; + remap_size = eps->num_of_4k_pages * PAGE_SIZE; +remap: /* * Get physical address of buffer and map to virtual address. * Table gives size in 4K pages, regardless of actual system page size. */ - if (upper_32_bits(eps->smm_comm_buff_addr + 8)) { - dev_warn(&dcdbas_pdev->dev, "found WSMT, but EPS buffer address is above 4GB\n"); + if (upper_32_bits(bios_buf_paddr + 8)) { + dev_warn(&dcdbas_pdev->dev, "found WSMT, but buffer address is above 4GB\n"); return -EINVAL; } /* * Limit remap size to MAX_SMI_DATA_BUF_SIZE + 8 (since the first 8 * bytes are used for a semaphore, not the data buffer itself). */ - remap_size = eps->num_of_4k_pages * PAGE_SIZE; if (remap_size > MAX_SMI_DATA_BUF_SIZE + 8) remap_size = MAX_SMI_DATA_BUF_SIZE + 8; - eps_buffer = memremap(eps->smm_comm_buff_addr, remap_size, MEMREMAP_WB); - if (!eps_buffer) { - dev_warn(&dcdbas_pdev->dev, "found WSMT, but failed to map EPS buffer\n"); + + bios_buffer = memremap(bios_buf_paddr, remap_size, MEMREMAP_WB); + if (!bios_buffer) { + dev_warn(&dcdbas_pdev->dev, "found WSMT, but failed to map buffer\n"); return -ENOMEM; } /* First 8 bytes is for a semaphore, not part of the smi_data_buf */ - smi_data_buf_phys_addr = eps->smm_comm_buff_addr + 8; - smi_data_buf = eps_buffer + 8; + smi_data_buf_phys_addr = bios_buf_paddr + 8; + smi_data_buf = bios_buffer + 8; smi_data_buf_size = remap_size - 8; max_smi_data_buf_size = smi_data_buf_size; wsmt_enabled = true; @@ -736,8 +753,8 @@ static void __exit dcdbas_exit(void) */ if (dcdbas_pdev) smi_data_buf_free(); - if (eps_buffer) - memunmap(eps_buffer); + if (bios_buffer) + memunmap(bios_buffer); platform_device_unregister(dcdbas_pdev_reg); platform_driver_unregister(&dcdbas_driver); } |