cleanup

[rpikern] / src / rpi.c

diff --git a/src/rpi.c b/src/rpi.c
new file mode 100644 (file)
index 0000000..ba39596
--- /dev/null
+++ b/src/rpi.c
@@ -0,0 +1,111 @@
+#include "rpi.h"
+#include "asm.h"
+
+#define IOREG(offs)            (*(volatile uint32_t*)(rpi_iobase | offs))
+
+/* System timer */
+#define STM_CTL_REG            IOREG(0x3000)
+#define STM_STAT_REG   STM_CTL_REG
+#define STM_LCNT_REG   IOREG(0x3004)
+#define STM_HCNT_REG   IOREG(0x3008)
+#define STM_CMP0_REG   IOREG(0x300c)
+#define STM_CMP1_REG   IOREG(0x3010)
+#define STM_CMP2_REG   IOREG(0x3014)
+#define STM_CMP3_REG   IOREG(0x3018)
+
+#define STMCTL_M0              1
+#define STMCTL_M1              2
+#define STMCTL_M2              4
+#define STMCTL_M3              8
+
+/* TIMER */
+#define TM_LOAD_REG            IOREG(0xb400)
+#define TM_VALUE_REG   IOREG(0xb404)
+#define TM_CTL_REG             IOREG(0xb408)
+#define TM_ICLR_REG            IOREG(0xb40c)
+#define TM_IRAW_REG            IOREG(0xb410)
+#define TM_IMSK_REG            IOREG(0xb414)
+#define TM_RELOAD_REG  IOREG(0xb418)
+#define TM_PREDIV_REG  IOREG(0xb41c)
+#define TM_COUNT_REG   IOREG(0xb420)
+
+#define TMCTL_23BIT            0x000002
+#define TMCTL_DIV16            0x000004
+#define TMCTL_DIV256   0x000008
+#define TMCTL_DIV1             0x00000c
+#define TMCTL_IEN              0x000020
+#define TMCTL_EN               0x000080
+#define TMCTL_DBGHALT  0x000100
+#define TMCTL_CNTEN            0x000200
+
+#define TMCTL_PRESCALER(x)     (((uint32_t)(x) & 0xff) << 16)
+
+
+/* MAILBOX */
+#define MBOX_READ_REG  IOREG(0xb880)
+#define MBOX_POLL_REG  IOREG(0xb890)
+#define MBOX_SENDER_REG        IOREG(0xb894)
+#define MBOX_STATUS_REG        IOREG(0xb898)
+#define MBOX_CFG_REG   IOREG(0xb89c)
+#define MBOX_WRITE_REG IOREG(0xb8a0)
+
+/* the full bit is set when there's no space to append messages */
+#define MBOX_STAT_FULL 0x80000000
+/* the empty bit is set when there are no pending messages to be read */
+#define MBOX_STAT_EMPTY        0x40000000
+
+static int detect(void);
+
+int rpi_model;
+uint32_t rpi_iobase;
+uint32_t rpi_memsize, rpi_vc_memsize;
+
+void rpi_init(void)
+{
+       if((rpi_model = detect()) == -1) {
+               for(;;) halt_cpu();
+       }
+
+       /* TODO */
+}
+
+static int detect(void)
+{
+       int i, j;
+       uint32_t tm0, tm1;
+       static uint32_t base[] = {0x20000000, 0x3f000000, 0xfe000000};
+
+       for(i=0; i<3; i++) {
+               rpi_iobase = base[i];
+               tm0 = STM_LCNT_REG;
+               for(j=0; j<256; j++) {
+                       tm1 = STM_LCNT_REG;
+               }
+               if(tm0 != tm1) {
+                       return i + 1;
+               }
+       }
+       return -1;
+}
+
+
+void rpi_mbox_send(int chan, uint32_t msg)
+{
+       while(MBOX_STATUS_REG & MBOX_STAT_FULL);
+       MBOX_WRITE_REG = (msg & 0xfffffff0) | chan;
+}
+
+uint32_t rpi_mbox_recv(int chan)
+{
+       uint32_t msg;
+       do {
+               while(MBOX_STATUS_REG & MBOX_STAT_EMPTY);
+               msg = MBOX_READ_REG;
+       } while((msg & 0xf) != chan);
+       return msg & 0xfffffff0;
+}
+
+int rpi_mbox_pending(int chan)
+{
+       return (MBOX_STATUS_REG & MBOX_STAT_EMPTY) == 0;
+}