pseries: SLOF PCI flag day

Currently on the pseries machine the SLOF firmware is used normally,
but we bypass it when -kernel is specified.  Having these two

different boot paths can cause some confusion.

In particular at present we need to "probe" the (emulated) PCI bus and
produce device tree nodes for the PCI devices in qemu, for the -kernel
case.  In the SLOF case, it takes the device tree from qemu adds some
stuff to it then passes it on to the kernel.

It's been decided that a better approach is to always boot through
SLOF, even when using -kernel.  WIth this approach we can leave PCI
probing and device node creation to SLOF in all cases which removes a
bunch of code in qemu, and avoids iterating the PCI devices from the
machine specific init code which we're not supposed to do.

This patch changes qemu to always boot through SLOF, and not to create
PCI nodes.  Simultaneously it updates the included version of SLOF
(submodule and binary image) to one which supports (and requires) the
new approach.

The new SLOF version also includes a number of unrelated enhancements:
support for booting from virtio-pci devices and e1000, greatly
improved FCode support and many bugfixes.  It also makes SLOF ready to
be used even when specifying a kernel on the qemu command line.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 91 insertions, 44 deletions

diff --git a/hw/spapr.c b/hw/spapr.c
index 0e1f80dfdc..b011371813 100644
--- a/hw/spapr.c
+++ b/hw/spapr.c
@@ -50,19 +50,29 @@
 
 #include <libfdt.h>
 
-#define KERNEL_LOAD_ADDR        0x00000000
-#define INITRD_LOAD_ADDR        0x02800000
+/* SLOF memory layout:
+ *
+ * SLOF raw image loaded at 0, copies its romfs right below the flat
+ * device-tree, then position SLOF itself 31M below that
+ *
+ * So we set FW_OVERHEAD to 40MB which should account for all of that
+ * and more
+ *
+ * We load our kernel at 4M, leaving space for SLOF initial image
+ */
 #define FDT_MAX_SIZE            0x10000
 #define RTAS_MAX_SIZE           0x10000
 #define FW_MAX_SIZE             0x400000
 #define FW_FILE_NAME            "slof.bin"
+#define FW_OVERHEAD             0x2800000
+#define KERNEL_LOAD_ADDR        FW_MAX_SIZE
 
-#define MIN_RMA_SLOF		128UL
+#define MIN_RMA_SLOF            128UL
 
 #define TIMEBASE_FREQ           512000000ULL
 
 #define MAX_CPUS                256
-#define XICS_IRQS		1024
+#define XICS_IRQS               1024
 
 #define SPAPR_PCI_BUID          0x800000020000001ULL
 #define SPAPR_PCI_MEM_WIN_ADDR  (0x10000000000ULL + 0xA0000000)
@@ -139,6 +149,7 @@ static void *spapr_create_fdt_skel(const char *cpu_model,
                                    target_phys_addr_t rma_size,
                                    target_phys_addr_t initrd_base,
                                    target_phys_addr_t initrd_size,
+                                   target_phys_addr_t kernel_size,
                                    const char *boot_device,
                                    const char *kernel_cmdline,
                                    long hash_shift)
@@ -176,6 +187,12 @@ static void *spapr_create_fdt_skel(const char *cpu_model,
     fdt = g_malloc0(FDT_MAX_SIZE);
     _FDT((fdt_create(fdt, FDT_MAX_SIZE)));
 
+    if (kernel_size) {
+        _FDT((fdt_add_reservemap_entry(fdt, KERNEL_LOAD_ADDR, kernel_size)));
+    }
+    if (initrd_size) {
+        _FDT((fdt_add_reservemap_entry(fdt, initrd_base, initrd_size)));
+    }
     _FDT((fdt_finish_reservemap(fdt)));
 
     /* Root node */
@@ -197,15 +214,13 @@ static void *spapr_create_fdt_skel(const char *cpu_model,
                        &start_prop, sizeof(start_prop))));
     _FDT((fdt_property(fdt, "linux,initrd-end",
                        &end_prop, sizeof(end_prop))));
-    _FDT((fdt_property_string(fdt, "qemu,boot-device", boot_device)));
+    if (kernel_size) {
+        uint64_t kprop[2] = { cpu_to_be64(KERNEL_LOAD_ADDR),
+                              cpu_to_be64(kernel_size) };
 
-    /*
-     * Because we don't always invoke any firmware, we can't rely on
-     * that to do BAR allocation.  Long term, we should probably do
-     * that ourselves, but for now, this setting (plus advertising the
-     * current BARs as 0) causes sufficiently recent kernels to to the
-     * BAR assignment themselves */
-    _FDT((fdt_property_cell(fdt, "linux,pci-probe-only", 0)));
+        _FDT((fdt_property(fdt, "qemu,boot-kernel", &kprop, sizeof(kprop))));
+    }
+    _FDT((fdt_property_string(fdt, "qemu,boot-device", boot_device)));
 
     _FDT((fdt_end_node(fdt)));
 
@@ -445,6 +460,12 @@ static void spapr_finalize_fdt(sPAPREnvironment *spapr,
 
     _FDT((fdt_pack(fdt)));
 
+    if (fdt_totalsize(fdt) > FDT_MAX_SIZE) {
+        hw_error("FDT too big ! 0x%x bytes (max is 0x%x)\n",
+                 fdt_totalsize(fdt), FDT_MAX_SIZE);
+        exit(1);
+    }
+
     cpu_physical_memory_write(fdt_addr, fdt, fdt_totalsize(fdt));
 
     g_free(fdt);
@@ -494,8 +515,9 @@ static void ppc_spapr_init(ram_addr_t ram_size,
     MemoryRegion *sysmem = get_system_memory();
     MemoryRegion *ram = g_new(MemoryRegion, 1);
     target_phys_addr_t rma_alloc_size, rma_size;
-    uint32_t initrd_base;
-    long kernel_size, initrd_size, fw_size;
+    uint32_t initrd_base = 0;
+    long kernel_size = 0, initrd_size = 0;
+    long load_limit, rtas_limit, fw_size;
     long pteg_shift = 17;
     char *filename;
 
@@ -517,11 +539,13 @@ static void ppc_spapr_init(ram_addr_t ram_size,
         rma_size = ram_size;
     }
 
-    /* We place the device tree just below either the top of the RMA,
+    /* We place the device tree and RTAS just below either the top of the RMA,
      * or just below 2GB, whichever is lowere, so that it can be
      * processed with 32-bit real mode code if necessary */
-    spapr->fdt_addr = MIN(rma_size, 0x80000000) - FDT_MAX_SIZE;
-    spapr->rtas_addr = spapr->fdt_addr - RTAS_MAX_SIZE;
+    rtas_limit = MIN(rma_size, 0x80000000);
+    spapr->rtas_addr = rtas_limit - RTAS_MAX_SIZE;
+    spapr->fdt_addr = spapr->rtas_addr - FDT_MAX_SIZE;
+    load_limit = spapr->fdt_addr - FW_OVERHEAD;
 
     /* init CPUs */
     if (cpu_model == NULL) {
@@ -577,13 +601,19 @@ static void ppc_spapr_init(ram_addr_t ram_size,
 
     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, "spapr-rtas.bin");
     spapr->rtas_size = load_image_targphys(filename, spapr->rtas_addr,
-                                           ram_size - spapr->rtas_addr);
+                                           rtas_limit - spapr->rtas_addr);
     if (spapr->rtas_size < 0) {
         hw_error("qemu: could not load LPAR rtas '%s'\n", filename);
         exit(1);
     }
+    if (spapr->rtas_size > RTAS_MAX_SIZE) {
+        hw_error("RTAS too big ! 0x%lx bytes (max is 0x%x)\n",
+                 spapr->rtas_size, RTAS_MAX_SIZE);
+        exit(1);
+    }
     g_free(filename);
 
+
     /* Set up Interrupt Controller */
     spapr->icp = xics_system_init(XICS_IRQS);
     spapr->next_irq = 16;
@@ -622,6 +652,20 @@ static void ppc_spapr_init(ram_addr_t ram_size,
         spapr_vscsi_create(spapr->vio_bus, 0x2000 + i);
     }
 
+    if (rma_size < (MIN_RMA_SLOF << 20)) {
+        fprintf(stderr, "qemu: pSeries SLOF firmware requires >= "
+                "%ldM guest RMA (Real Mode Area memory)\n", MIN_RMA_SLOF);
+        exit(1);
+    }
+
+    fprintf(stderr, "sPAPR memory map:\n");
+    fprintf(stderr, "RTAS                 : 0x%08lx..%08lx\n",
+            (unsigned long)spapr->rtas_addr,
+            (unsigned long)(spapr->rtas_addr + spapr->rtas_size - 1));
+    fprintf(stderr, "FDT                  : 0x%08lx..%08lx\n",
+            (unsigned long)spapr->fdt_addr,
+            (unsigned long)(spapr->fdt_addr + FDT_MAX_SIZE - 1));
+
     if (kernel_filename) {
         uint64_t lowaddr = 0;
 
@@ -630,57 +674,60 @@ static void ppc_spapr_init(ram_addr_t ram_size,
         if (kernel_size < 0) {
             kernel_size = load_image_targphys(kernel_filename,
                                               KERNEL_LOAD_ADDR,
-                                              ram_size - KERNEL_LOAD_ADDR);
+                                              load_limit - KERNEL_LOAD_ADDR);
         }
         if (kernel_size < 0) {
             fprintf(stderr, "qemu: could not load kernel '%s'\n",
                     kernel_filename);
             exit(1);
         }
+        fprintf(stderr, "Kernel               : 0x%08x..%08lx\n",
+                KERNEL_LOAD_ADDR, KERNEL_LOAD_ADDR + kernel_size - 1);
 
         /* load initrd */
         if (initrd_filename) {
-            initrd_base = INITRD_LOAD_ADDR;
+            /* Try to locate the initrd in the gap between the kernel
+             * and the firmware. Add a bit of space just in case
+             */
+            initrd_base = (KERNEL_LOAD_ADDR + kernel_size + 0x1ffff) & ~0xffff;
             initrd_size = load_image_targphys(initrd_filename, initrd_base,
-                                              ram_size - initrd_base);
+                                              load_limit - initrd_base);
             if (initrd_size < 0) {
                 fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
                         initrd_filename);
                 exit(1);
             }
+            fprintf(stderr, "Ramdisk              : 0x%08lx..%08lx\n",
+                    (long)initrd_base, (long)(initrd_base + initrd_size - 1));
         } else {
             initrd_base = 0;
             initrd_size = 0;
         }
+    }
 
-        spapr->entry_point = KERNEL_LOAD_ADDR;
-    } else {
-        if (rma_size < (MIN_RMA_SLOF << 20)) {
-            fprintf(stderr, "qemu: pSeries SLOF firmware requires >= "
-                    "%ldM guest RMA (Real Mode Area memory)\n", MIN_RMA_SLOF);
-            exit(1);
-        }
-        filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, FW_FILE_NAME);
-        fw_size = load_image_targphys(filename, 0, FW_MAX_SIZE);
-        if (fw_size < 0) {
-            hw_error("qemu: could not load LPAR rtas '%s'\n", filename);
-            exit(1);
-        }
-        g_free(filename);
-        spapr->entry_point = 0x100;
-        initrd_base = 0;
-        initrd_size = 0;
-
-        /* SLOF will startup the secondary CPUs using RTAS,
-           rather than expecting a kexec() style entry */
-        for (env = first_cpu; env != NULL; env = env->next_cpu) {
-            env->halted = 1;
-        }
+    filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, FW_FILE_NAME);
+    fw_size = load_image_targphys(filename, 0, FW_MAX_SIZE);
+    if (fw_size < 0) {
+        hw_error("qemu: could not load LPAR rtas '%s'\n", filename);
+        exit(1);
+    }
+    g_free(filename);
+    fprintf(stderr, "Firmware load        : 0x%08x..%08lx\n",
+            0, fw_size);
+    fprintf(stderr, "Firmware runtime     : 0x%08lx..%08lx\n",
+            load_limit, (unsigned long)spapr->fdt_addr);
+
+    spapr->entry_point = 0x100;
+
+    /* SLOF will startup the secondary CPUs using RTAS */
+    for (env = first_cpu; env != NULL; env = env->next_cpu) {
+        env->halted = 1;
     }
 
     /* Prepare the device tree */
     spapr->fdt_skel = spapr_create_fdt_skel(cpu_model, rma_size,
                                             initrd_base, initrd_size,
+                                            kernel_size,
                                             boot_device, kernel_cmdline,
                                             pteg_shift + 7);
     assert(spapr->fdt_skel != NULL);