[POWERPC] 8xx: powerpc port of core CPM PIC

This covers common CPM access functions, CPM interrupt controller code,
micropatch and a few compatibility things to kee the same driver base
working with arch/ppc. This version is refined with all the comments
(mostly PIC-related) addressed.

Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 398 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/commproc.c b/arch/powerpc/sysdev/commproc.c
new file mode 100644
index 000000000000..9b4fafd9a840
--- /dev/null
+++ b/arch/powerpc/sysdev/commproc.c
@@ -0,0 +1,398 @@
+/*
+ * General Purpose functions for the global management of the
+ * Communication Processor Module.
+ * Copyright (c) 1997 Dan error_act (dmalek@jlc.net)
+ *
+ * In addition to the individual control of the communication
+ * channels, there are a few functions that globally affect the
+ * communication processor.
+ *
+ * Buffer descriptors must be allocated from the dual ported memory
+ * space.  The allocator for that is here.  When the communication
+ * process is reset, we reclaim the memory available.  There is
+ * currently no deallocator for this memory.
+ * The amount of space available is platform dependent.  On the
+ * MBX, the EPPC software loads additional microcode into the
+ * communication processor, and uses some of the DP ram for this
+ * purpose.  Current, the first 512 bytes and the last 256 bytes of
+ * memory are used.  Right now I am conservative and only use the
+ * memory that can never be used for microcode.  If there are
+ * applications that require more DP ram, we can expand the boundaries
+ * but then we have to be careful of any downloaded microcode.
+ */
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/dma-mapping.h>
+#include <linux/param.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <asm/mpc8xx.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/8xx_immap.h>
+#include <asm/commproc.h>
+#include <asm/io.h>
+#include <asm/tlbflush.h>
+#include <asm/rheap.h>
+#include <asm/prom.h>
+
+#include <asm/fs_pd.h>
+
+#define CPM_MAP_SIZE    (0x4000)
+
+static void m8xx_cpm_dpinit(void);
+static  uint    host_buffer;    /* One page of host buffer */
+static  uint    host_end;       /* end + 1 */
+cpm8xx_t        *cpmp;          /* Pointer to comm processor space */
+cpic8xx_t       *cpic_reg;
+
+static struct device_node *cpm_pic_node;
+static struct irq_host *cpm_pic_host;
+
+static void cpm_mask_irq(unsigned int irq)
+{
+        unsigned int cpm_vec = (unsigned int)irq_map[irq].hwirq;
+
+        clrbits32(&cpic_reg->cpic_cimr, (1 << cpm_vec));
+}
+
+static void cpm_unmask_irq(unsigned int irq)
+{
+        unsigned int cpm_vec = (unsigned int)irq_map[irq].hwirq;
+
+        setbits32(&cpic_reg->cpic_cimr, (1 << cpm_vec));
+}
+
+static void cpm_end_irq(unsigned int irq)
+{
+        unsigned int cpm_vec = (unsigned int)irq_map[irq].hwirq;
+
+        out_be32(&cpic_reg->cpic_cisr, (1 << cpm_vec));
+}
+
+static struct irq_chip cpm_pic = {
+        .typename = " CPM PIC ",
+        .mask = cpm_mask_irq,
+        .unmask = cpm_unmask_irq,
+        .eoi = cpm_end_irq,
+};
+
+int cpm_get_irq(void)
+{
+        int cpm_vec;
+
+        /* Get the vector by setting the ACK bit and then reading
+         * the register.
+         */
+        out_be16(&cpic_reg->cpic_civr, 1);
+        cpm_vec = in_be16(&cpic_reg->cpic_civr);
+        cpm_vec >>= 11;
+
+        return irq_linear_revmap(cpm_pic_host, cpm_vec);
+}
+
+static int cpm_pic_host_match(struct irq_host *h, struct device_node *node)
+{
+        return cpm_pic_node == node;
+}
+
+static int cpm_pic_host_map(struct irq_host *h, unsigned int virq,
+                          irq_hw_number_t hw)
+{
+        pr_debug("cpm_pic_host_map(%d, 0x%lx)\n", virq, hw);
+
+        get_irq_desc(virq)->status |= IRQ_LEVEL;
+        set_irq_chip_and_handler(virq, &cpm_pic, handle_fasteoi_irq);
+        return 0;
+}
+
+/* The CPM can generate the error interrupt when there is a race condition
+ * between generating and masking interrupts.  All we have to do is ACK it
+ * and return.  This is a no-op function so we don't need any special
+ * tests in the interrupt handler.
+ */
+static  irqreturn_t cpm_error_interrupt(int irq, void *dev)
+{
+        return IRQ_HANDLED;
+}
+
+static struct irqaction cpm_error_irqaction = {
+        .handler = cpm_error_interrupt,
+        .mask = CPU_MASK_NONE,
+        .name = "error",
+};
+
+static struct irq_host_ops cpm_pic_host_ops = {
+        .match = cpm_pic_host_match,
+        .map = cpm_pic_host_map,
+};
+
+unsigned int cpm_pic_init(void)
+{
+        struct device_node *np = NULL;
+        struct resource res;
+        unsigned int sirq = NO_IRQ, hwirq, eirq;
+        int ret;
+
+        pr_debug("cpm_pic_init\n");
+
+        np = of_find_compatible_node(NULL, "cpm-pic", "CPM");
+        if (np == NULL) {
+                printk(KERN_ERR "CPM PIC init: can not find cpm-pic node\n");
+                return sirq;
+        }
+        ret = of_address_to_resource(np, 0, &res);
+        if (ret)
+                goto end;
+
+        cpic_reg = (void *)ioremap(res.start, res.end - res.start + 1);
+        if (cpic_reg == NULL)
+                goto end;
+
+        sirq = irq_of_parse_and_map(np, 0);
+        if (sirq == NO_IRQ)
+                goto end;
+
+        /* Initialize the CPM interrupt controller. */
+        hwirq = (unsigned int)irq_map[sirq].hwirq;
+        out_be32(&cpic_reg->cpic_cicr,
+            (CICR_SCD_SCC4 | CICR_SCC_SCC3 | CICR_SCB_SCC2 | CICR_SCA_SCC1) |
+                ((hwirq/2) << 13) | CICR_HP_MASK);
+
+        out_be32(&cpic_reg->cpic_cimr, 0);
+
+        cpm_pic_node = of_node_get(np);
+
+        cpm_pic_host = irq_alloc_host(IRQ_HOST_MAP_LINEAR, 64, &cpm_pic_host_ops, 64);
+        if (cpm_pic_host == NULL) {
+                printk(KERN_ERR "CPM2 PIC: failed to allocate irq host!\n");
+                sirq = NO_IRQ;
+                goto end;
+        }
+        of_node_put(np);
+
+        /* Install our own error handler. */
+        np = of_find_node_by_type(NULL, "cpm");
+        if (np == NULL) {
+                printk(KERN_ERR "CPM PIC init: can not find cpm node\n");
+                goto end;
+        }
+        eirq= irq_of_parse_and_map(np, 0);
+        if (eirq == NO_IRQ)
+                goto end;
+
+        if (setup_irq(eirq, &cpm_error_irqaction))
+                printk(KERN_ERR "Could not allocate CPM error IRQ!");
+
+        setbits32(&cpic_reg->cpic_cicr, CICR_IEN);
+
+end:
+        of_node_put(np);
+        return sirq;
+}
+
+void cpm_reset(void)
+{
+        cpm8xx_t        *commproc;
+        sysconf8xx_t    *siu_conf;
+
+        commproc = (cpm8xx_t *)ioremap(CPM_MAP_ADDR, CPM_MAP_SIZE);
+
+#ifdef CONFIG_UCODE_PATCH
+        /* Perform a reset.
+        */
+        out_be16(&commproc->cp_cpcr,  CPM_CR_RST | CPM_CR_FLG);
+
+        /* Wait for it.
+        */
+        while (in_be16(&commproc->cp_cpcr) & CPM_CR_FLG);
+
+        cpm_load_patch(commproc);
+#endif
+
+        /* Set SDMA Bus Request priority 5.
+         * On 860T, this also enables FEC priority 6.  I am not sure
+         * this is what we realy want for some applications, but the
+         * manual recommends it.
+         * Bit 25, FAM can also be set to use FEC aggressive mode (860T).
+         */
+        siu_conf = (sysconf8xx_t*)immr_map(im_siu_conf);
+        out_be32(&siu_conf->sc_sdcr, 1);
+        immr_unmap(siu_conf);
+
+        /* Reclaim the DP memory for our use. */
+        m8xx_cpm_dpinit();
+
+        /* Tell everyone where the comm processor resides.
+        */
+        cpmp = commproc;
+}
+
+/* We used to do this earlier, but have to postpone as long as possible
+ * to ensure the kernel VM is now running.
+ */
+static void
+alloc_host_memory(void)
+{
+        dma_addr_t      physaddr;
+
+        /* Set the host page for allocation.
+        */
+        host_buffer = (uint)dma_alloc_coherent(NULL, PAGE_SIZE, &physaddr,
+                        GFP_KERNEL);
+        host_end = host_buffer + PAGE_SIZE;
+}
+
+/* We also own one page of host buffer space for the allocation of
+ * UART "fifos" and the like.
+ */
+uint
+m8xx_cpm_hostalloc(uint size)
+{
+        uint    retloc;
+
+        if (host_buffer == 0)
+                alloc_host_memory();
+
+        if ((host_buffer + size) >= host_end)
+                return(0);
+
+        retloc = host_buffer;
+        host_buffer += size;
+
+        return(retloc);
+}
+
+/* Set a baud rate generator.  This needs lots of work.  There are
+ * four BRGs, any of which can be wired to any channel.
+ * The internal baud rate clock is the system clock divided by 16.
+ * This assumes the baudrate is 16x oversampled by the uart.
+ */
+#define BRG_INT_CLK             (get_brgfreq())
+#define BRG_UART_CLK            (BRG_INT_CLK/16)
+#define BRG_UART_CLK_DIV16      (BRG_UART_CLK/16)
+
+void
+cpm_setbrg(uint brg, uint rate)
+{
+        volatile uint   *bp;
+
+        /* This is good enough to get SMCs running.....
+        */
+        bp = (uint *)&cpmp->cp_brgc1;
+        bp += brg;
+        /* The BRG has a 12-bit counter.  For really slow baud rates (or
+         * really fast processors), we may have to further divide by 16.
+         */
+        if (((BRG_UART_CLK / rate) - 1) < 4096)
+                *bp = (((BRG_UART_CLK / rate) - 1) << 1) | CPM_BRG_EN;
+        else
+                *bp = (((BRG_UART_CLK_DIV16 / rate) - 1) << 1) |
+                                                CPM_BRG_EN | CPM_BRG_DIV16;
+}
+
+/*
+ * dpalloc / dpfree bits.
+ */
+static spinlock_t cpm_dpmem_lock;
+/*
+ * 16 blocks should be enough to satisfy all requests
+ * until the memory subsystem goes up...
+ */
+static rh_block_t cpm_boot_dpmem_rh_block[16];
+static rh_info_t cpm_dpmem_info;
+
+#define CPM_DPMEM_ALIGNMENT     8
+static u8* dpram_vbase;
+static uint dpram_pbase;
+
+void m8xx_cpm_dpinit(void)
+{
+        spin_lock_init(&cpm_dpmem_lock);
+
+        dpram_vbase = immr_map_size(im_cpm.cp_dpmem, CPM_DATAONLY_BASE + CPM_DATAONLY_SIZE);
+        dpram_pbase = (uint)&((immap_t *)IMAP_ADDR)->im_cpm.cp_dpmem;
+
+        /* Initialize the info header */
+        rh_init(&cpm_dpmem_info, CPM_DPMEM_ALIGNMENT,
+                        sizeof(cpm_boot_dpmem_rh_block) /
+                        sizeof(cpm_boot_dpmem_rh_block[0]),
+                        cpm_boot_dpmem_rh_block);
+
+        /*
+         * Attach the usable dpmem area.
+         * XXX: This is actually crap.  CPM_DATAONLY_BASE and
+         * CPM_DATAONLY_SIZE are a subset of the available dparm.  It varies
+         * with the processor and the microcode patches applied / activated.
+         * But the following should be at least safe.
+         */
+        rh_attach_region(&cpm_dpmem_info, (void *)CPM_DATAONLY_BASE, CPM_DATAONLY_SIZE);
+}
+
+/*
+ * Allocate the requested size worth of DP memory.
+ * This function returns an offset into the DPRAM area.
+ * Use cpm_dpram_addr() to get the virtual address of the area.
+ */
+uint cpm_dpalloc(uint size, uint align)
+{
+        void *start;
+        unsigned long flags;
+
+        spin_lock_irqsave(&cpm_dpmem_lock, flags);
+        cpm_dpmem_info.alignment = align;
+        start = rh_alloc(&cpm_dpmem_info, size, "commproc");
+        spin_unlock_irqrestore(&cpm_dpmem_lock, flags);
+
+        return (uint)start;
+}
+EXPORT_SYMBOL(cpm_dpalloc);
+
+int cpm_dpfree(uint offset)
+{
+        int ret;
+        unsigned long flags;
+
+        spin_lock_irqsave(&cpm_dpmem_lock, flags);
+        ret = rh_free(&cpm_dpmem_info, (void *)offset);
+        spin_unlock_irqrestore(&cpm_dpmem_lock, flags);
+
+        return ret;
+}
+EXPORT_SYMBOL(cpm_dpfree);
+
+uint cpm_dpalloc_fixed(uint offset, uint size, uint align)
+{
+        void *start;
+        unsigned long flags;
+
+        spin_lock_irqsave(&cpm_dpmem_lock, flags);
+        cpm_dpmem_info.alignment = align;
+        start = rh_alloc_fixed(&cpm_dpmem_info, (void *)offset, size, "commproc");
+        spin_unlock_irqrestore(&cpm_dpmem_lock, flags);
+
+        return (uint)start;
+}
+EXPORT_SYMBOL(cpm_dpalloc_fixed);
+
+void cpm_dpdump(void)
+{
+        rh_dump(&cpm_dpmem_info);
+}
+EXPORT_SYMBOL(cpm_dpdump);
+
+void *cpm_dpram_addr(uint offset)
+{
+        return (void *)(dpram_vbase + offset);
+}
+EXPORT_SYMBOL(cpm_dpram_addr);
+
+uint cpm_dpram_phys(u8* addr)
+{
+        return (dpram_pbase + (uint)(addr - dpram_vbase));
+}
+EXPORT_SYMBOL(cpm_dpram_addr);