x86: Support use of PCI before relocation

Add support for using PCI before SDRAM is available, using early malloc()
and global_data.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/arch/x86/cpu/pci.c b/arch/x86/cpu/pci.c
index 0741dc2..2d8f16c 100644 (file)
--- a/arch/x86/cpu/pci.c
+++ b/arch/x86/cpu/pci.c
@@ -10,15 +10,36 @@
  */
 
 #include <common.h>
+#include <errno.h>
+#include <malloc.h>
 #include <pci.h>
 #include <asm/pci.h>
 
 static struct pci_controller x86_hose;
 
+int pci_early_init_hose(struct pci_controller **hosep)
+{
+       struct pci_controller *hose;
+
+       hose = calloc(1, sizeof(struct pci_controller));
+       if (!hose)
+               return -ENOMEM;
+
+       board_pci_setup_hose(hose);
+       pci_setup_type1(hose);
+       gd->arch.hose = hose;
+       *hosep = hose;
+
+       return 0;
+}
+
 void pci_init_board(void)
 {
        struct pci_controller *hose = &x86_hose;
 
+       /* Stop using the early hose */
+       gd->arch.hose = NULL;
+
        board_pci_setup_hose(hose);
        pci_setup_type1(hose);
        pci_register_hose(hose);

diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index 186b97e..d32987b 100644 (file)
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -24,6 +24,7 @@ struct arch_global_data {
        uint32_t tsc_mhz;               /* TSC frequency in MHz */
        void *new_fdt;                  /* Relocated FDT */
        uint32_t bist;                  /* Built-in self test value */
+       struct pci_controller *hose;    /* PCI hose for early use */
 };
 
 #endif

diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index c160707..6e70a99 100644 (file)
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -24,4 +24,13 @@ void pci_setup_type1(struct pci_controller *hose);
  * store things in 'hose' and not in BSS variables.
  */
 void board_pci_setup_hose(struct pci_controller *hose);
+
+/**
+ * pci_early_init_hose() - Set up PCI host before relocation
+ *
+ * This allocates memory for, sets up and returns the PCI hose. It can be
+ * called before relocation. The hose will be stored in gd->arch.hose for
+ * later use, but will become invalid one DRAM is available.
+ */
+int pci_early_init_hose(struct pci_controller **hosep);
 #endif